Cisco Industrial Ethernet 4000, 4010 and 5000 Switch Software. Configuration Guide (2022)

Working with the Cisco IOS File System, Configuration Files, and Software Images

Working with Software Images

Table 69

info File Description (continued)

Field

Description

total_image_file_size

Specifies the size of all the images (the Cisco IOS image and the web management files) in the

tar file, which is an approximate measure of how much flash memory is required to hold them.

image_feature

Describes the core functionality of the image.

image_min_dram

Specifies the minimum amount of DRAM needed to run this image.

image_family

Describes the family of products on which the software can be installed.

Copying Image Files By Using TFTP

You can download a switch image from a TFTP server or upload the image from the switch to a TFTP server.

You download a switch image file from a server to upgrade the switch software. You can overwrite the current image with

the new one or keep the current image after a download.

You upload a switch image file to a server for backup purposes; this uploaded image can be used for future downloads

to the same or another switch of the same type.

Note: Instead of using the copy privileged EXEC command or the archive tar privileged EXEC command, we recommend

using the archive download-sw and archive upload-sw privileged EXEC commands to download and upload software

image files.

Preparing to Download or Upload an Image File By Using TFTP

Before you begin downloading or uploading an image file by using TFTP, do these tasks:

Ensure that the workstation acting as the TFTP server is properly configured. On a Sun workstation, make sure that

the /etc/inetd.conf file contains this line:

tftp dgram udp wait root /usr/etc/in.tftpd in.tftpd -p -s /tftpboot

Make sure that the /etc/services file contains this line:

tftp 69/udp

You must restart the inetd daemon after modifying the /etc/inetd.conf and /etc/services files. To restart the

daemon, either stop the inetd process and restart it, or enter a fastboot command (on the SunOS 4.x) or a reboot

command (on Solaris 2.x or SunOS 5.x). For more information on the TFTP daemon, see the documentation for

your workstation.

Ensure that the switch has a route to the TFTP server. The switch and the TFTP server must be in the same

subnetwork if you do not have a router to route traffic between subnets. Check connectivity to the TFTP server by

using the ping command.

Ensure that the image to be downloaded is in the correct directory on the TFTP server (usually /tftpboot on a UNIX

workstation).

For download operations, ensure that the permissions on the file are set correctly. The permission on the file should

be world-read.

Before uploading the image file, you might need to create an empty file on the TFTP server. To create an empty file,

enter the touch filename command, where filename is the name of the file you will use when uploading the image

to the server.

During upload operations, if you are overwriting an existing file (including an empty file, if you had to create one) on

the server, ensure that the permissions on the file are set correctly. Permissions on the file should be world-write.

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Downloading an Image File By Using TFTP

You can download a new image file and replace the current image or keep the current image.

Beginning in privileged EXEC mode, follow Steps 1 through 3 to download a new image from a TFTP server and overwrite

the existing image. To keep the current image, go to Step 3.

Command

Purpose

Copy the image to the appropriate TFTP

directory on the workstation. Make sure that

the TFTP server is properly configured; see the

Preparing to Download or Upload an Image File

By Using TFTP, page 1057.

Log into the switch through the console port or

a Telnet session.

archive download-sw /overwrite /reload

Downloads the image file from the TFTP server to the switch, and

tftp:[[//location]/directory]/image-name.tar

overwrite the current image.

The /overwrite option overwrites the software image in flash

memory with the downloaded image.

The /reload option reloads the system after downloading the

image unless the configuration has been changed and not

been saved.

For //location, specify the IP address of the TFTP server.

For /directory/image-name.tar, specify the directory (optional)

and the image to download. Directory and image names are

case sensitive.

archive download-sw /leave-old-sw /reload

Downloads the image file from the TFTP server to the switch, and

tftp:[[//location]/directory]/image-name.tar

keep the current image.

The /leave-old-sw option keeps the old software version after

a download.

The /reload option reloads the system after downloading the

image unless the configuration has been changed and not

been saved.

For //location, specify the IP address of the TFTP server.

For /directory/image-name.tar, specify the directory (optional)

and the image to download. Directory and image names are

case sensitive.

The download algorithm verifies that the image is appropriate for the switch model and that enough DRAM is present, or

it aborts the process and reports an error. If you specify the /overwrite option, the download algorithm removes the

existing image on the flash device whether or not it is the same as the new one, downloads the new image, and then

reloads the software.

Note: If the flash device has sufficient space to hold two images and you want to overwrite one of these images with the

same version, you must specify the /overwrite option.

If you specify the /leave-old-sw, the existing files are not removed. If there is not enough space to install the new image

and keep the running image, the download process stops, and an error message is displayed.

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Working with Software Images

The algorithm installs the downloaded image on the system board flash device (flash:). The image is placed into a new

directory named with the software version string, and the BOOT environment variable is updated to point to the newly

installed image.

If you kept the old image during the download process (you specified the /leave-old-sw keyword), you can remove it by

entering the delete /force /recursive filesystem:/file-url privileged EXEC command. For filesystem, use flash: for the

system board flash device. For file-url, enter the directory name of the old image. All the files in the directory and the

directory are removed.

Caution: For the download and upload algorithms to operate properly, do not rename image names.

Uploading an Image File By Using TFTP

You can upload an image from the switch to a TFTP server. You can later download this image to the switch or to another

switch of the same type.

Use the upload feature only if the web management pages associated with the embedded Device Manager have been

installed with the existing image.

Beginning in privileged EXEC mode, follow these steps to upload an image to a TFTP server:

Command

Purpose

Make sure the TFTP server is properly

configured; see the Preparing to Download or

Upload an Image File By Using TFTP,

page 1057.

Log into the switch through the console port or

a Telnet session.

archive upload-sw

Uploads the currently running switch image to the TFTP server.

tftp:[[//location]/directory]/image-name.tar

For //location, specify the IP address of the TFTP server.

For /directory/image-name.tar, specify the directory (optional)

and the name of the software image to be uploaded. Directory

and image names are case sensitive. The image-name.tar is

the name of the software image to be stored on the server.

The archive upload-sw privileged EXEC command builds an image file on the server by uploading these files in order:

info, the Cisco IOS image, and the web management files. After these files are uploaded, the upload algorithm creates

the tar file format.

Caution: For the download and upload algorithms to operate properly, do not rename image names.

Copying Image Files By Using FTP

You can download a switch image from an FTP server or upload the image from the switch to an FTP server.

You download a switch image file from a server to upgrade the switch software. You can overwrite the current image with

the new one or keep the current image after a download.

You upload a switch image file to a server for backup purposes. You can use this uploaded image for future downloads

to the switch or another switch of the same type.

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Working with Software Images

Note: Instead of using the copy privileged EXEC command or the archive tar privileged EXEC command, we recommend

using the archive download-sw and archive upload-sw privileged EXEC commands to download and upload software

image files.

Preparing to Download or Upload an Image File By Using FTP

You can copy images files to or from an FTP server.

The FTP protocol requires a client to send a remote username and password on each FTP request to a server. When you

copy an image file from the switch to a server by using FTP, the Cisco IOS software sends the first valid username in this

list:

The username specified in the archive download-sw or archive upload-sw privileged EXEC command if a

username is specified.

The username set by the ip ftp username username global configuration command if the command is configured.

Anonymous.

The switch sends the first valid password in this list:

The password specified in the archive download-sw or archive upload-sw privileged EXEC command if a

password is specified.

The password set by the ip ftp password password global configuration command if the command is configured.

The switch forms a password named username@switchname.domain. The variable username is the username

associated with the current session, switchname is the configured hostname, and domain is the domain of the

switch.

The username and password must be associated with an account on the FTP server. If you are writing to the server, the

FTP server must be properly configured to accept the FTP write request from you.

Use the ip ftp username and ip ftp password commands to specify a username and password for all copies. Include

the username in the archive download-sw or archive upload-sw privileged EXEC command if you want to specify a

username only for that operation.

If the server has a directory structure, the image file is written to or copied from the directory associated with the

username on the server. For example, if the image file resides in the home directory of a user on the server, specify that

user's name as the remote username.

Before you begin downloading or uploading an image file by using FTP, do these tasks:

Ensure that the switch has a route to the FTP server. The switch and the FTP server must be in the same subnetwork

if you do not have a router to route traffic between subnets. Check connectivity to the FTP server by using the ping

command.

If you are accessing the switch through the console or a Telnet session and you do not have a valid username, make

sure that the current FTP username is the one that you want to use for the FTP download. You can enter the show

users privileged EXEC command to view the valid username. If you do not want to use this username, create a new

FTP username by using the ip ftp username username global configuration command. This new name will be used

during all archive operations. The new username is stored in NVRAM. If you are accessing the switch through a Telnet

session and you have a valid username, this username is used, and you do not need to set the FTP username. Include

the username in the archive download-sw or archive upload-sw privileged EXEC command if you want to specify

a username for that operation only.

When you upload an image file to the FTP server, it must be properly configured to accept the write request from

the user on the switch.

For more information, see the documentation for your FTP server.

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Working with Software Images

Downloading an Image File By Using FTP

You can download a new image file and overwrite the current image or keep the current image.

Beginning in privileged EXEC mode, follow Steps 1 through 7 to download a new image from an FTP server and overwrite

the existing image. To keep the current image, go to Step 7.

Command

Purpose

Verify that the FTP server is properly configured by

referring to the Preparing to Download or Upload a

Configuration File By Using FTP, page 1046.

Log into the switch through the console port or a

Telnet session.

configure terminal

Enters global configuration mode.

This step is required only if you override the default remote

username or password (see Steps 4, 5, and 6).

ip ftp username username

(Optional) Changes the default remote username.

ip ftp password password

(Optional) Changes the default password.

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Working with Software Images

Command

Purpose

end

Returns to privileged EXEC mode.

archive download-sw /overwrite /reload

Downloads the image file from the FTP server to the switch,

ftp:[[//username[:password]@location]/directory]/i

and overwrite the current image.

mage-name.tar

The /overwrite option overwrites the software image in

flash memory with the downloaded image.

The /reload option reloads the system after downloading

the image unless the configuration has been changed and

not been saved.

For //username[:password], specify the username and

password; these must be associated with an account on

the FTP server.

For @location, specify the IP address of the FTP server.

For directory/image-name.tar, specify the directory

(optional) and the image to download. Directory and

image names are case sensitive.

archive download-sw /leave-old-sw /reload

Downloads the image file from the FTP server to the switch,

ftp:[[//username[:password]@location]/directory]/i

and keep the current image.

mage-name.tar

The /leave-old-sw option keeps the old software version

after a download.

The /reload option reloads the system after downloading

the image unless the configuration has been changed and

not been saved.

For //username[:password], specify the username and

password. These must be associated with an account on

the FTP server.

For @location, specify the IP address of the FTP server.

For directory/image-name.tar, specify the directory

(optional) and the image to download. Directory and

image names are case sensitive.

The download algorithm verifies that the image is appropriate for the switch model and that enough DRAM is present, or

it aborts the process and reports an error. If you specify the /overwrite option, the download algorithm removes the

existing image on the flash device, whether or not it is the same as the new one, downloads the new image, and then

reloads the software.

Note: If the flash device has sufficient space to hold two images and you want to overwrite one of these images with the

same version, you must specify the /overwrite option.

If you specify the /leave-old-sw, the existing files are not removed. If there is not enough space to install the new image

and keep the running image, the download process stops, and an error message is displayed.

The algorithm installs the downloaded image onto the system board flash device (flash:). The image is placed into a new

directory named with the software version string, and the BOOT environment variable is updated to point to the newly

installed image.

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Working with Software Images

If you kept the old image during the download process (you specified the /leave-old-sw keyword), you can remove it by

entering the delete /force /recursive filesystem:/file-url privileged EXEC command. For filesystem, use flash: for the

system board flash device. For file-url, enter the directory name of the old software image. All the files in the directory

and the directory are removed.

Caution: For the download and upload algorithms to operate properly, do not rename image names.

Uploading an Image File By Using FTP

You can upload an image from the switch to an FTP server. You can later download this image to the same switch or to

another switch of the same type.

Use the upload feature only if the web management pages associated with the embedded Device Manager have been

installed with the existing image.

Beginning in privileged EXEC mode, follow these steps to upload an image to an FTP server:

Command

Purpose

Verify that the FTP server is properly configured by

referring to the Preparing to Download or Upload a

Configuration File By Using FTP, page 1046.

Log into the switch through the console port or a

Telnet session.

configure terminal

Enters global configuration mode.

This step is required only if you override the default remote

username or password (see Steps 4, 5, and 6).

ip ftp username username

(Optional) Changes the default remote username.

ip ftp password password

(Optional) Changes the default password.

end

Returns to privileged EXEC mode.

archive upload-sw

Uploads the currently running switch image to the FTP

ftp:[[//[username[:password]@]location]/directory]/i

server.

mage-name.tar

For //username:password, specify the username and

password. These must be associated with an account

on the FTP server.

For @location, specify the IP address of the FTP server.

For /directory/image-name.tar, specify the directory

(optional) and the name of the software image to be

uploaded. Directory and image names are case

sensitive. The image-name.tar is the name of the

software image to be stored on the server.

The archive upload-sw command builds an image file on the server by uploading these files in order: info, the Cisco

IOS image, and the web management files. After these files are uploaded, the upload algorithm creates the tar file format.

Caution: For the download and upload algorithms to operate properly, do not rename image names.

Copying Image Files By Using RCP

You can download a switch image from an RCP server or upload the image from the switch to an RCP server.

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Working with Software Images

You download a switch image file from a server to upgrade the switch software. You can overwrite the current image with

the new one or keep the current image after a download.

You upload a switch image file to a server for backup purposes. You can use this uploaded image for future downloads

to the same switch or another of the same type.

Note: Instead of using the copy privileged EXEC command or the archive tar privileged EXEC command, we recommend

using the archive download-sw and archive upload-sw privileged EXEC commands to download and upload software

image files.

Preparing to Download or Upload an Image File By Using RCP

RCP provides another method of downloading and uploading image files between remote hosts and the switch. Unlike

TFTP, which uses User Datagram Protocol (UDP), a connectionless protocol, RCP uses TCP, which is

connection-oriented.

To use RCP to copy files, the server from or to which you will be copying files must support RCP. The RCP copy

commands rely on the rsh server (or daemon) on the remote system. To copy files by using RCP, you do not need to

create a server for file distribution as you do with TFTP. You only need to have access to a server that supports the remote

shell (rsh). (Most UNIX systems support rsh.) Because you are copying a file from one place to another, you must have

read permission on the source file and write permission on the destination file. If the destination file does not exist, RCP

creates it for you.

RCP requires a client to send a remote username on each RCP request to a server. When you copy an image from the

switch to a server by using RCP, the Cisco IOS software sends the first valid username in this list:

The username specified in the archive download-sw or archive upload-sw privileged EXEC command if a

username is specified.

The username set by the ip rcmd remote-username username global configuration command if the command is

entered.

The remote username associated with the current TTY (terminal) process. For example, if the user is connected to

the router through Telnet and was authenticated through the username command, the switch software sends the

Telnet username as the remote username.

The switch hostname.

For the RCP copy request to execute successfully, an account must be defined on the network server for the remote

username. If the server has a directory structure, the image file is written to or copied from the directory associated with

the remote username on the server. For example, if the image file resides in the home directory of a user on the server,

specify that user’s name as the remote username.

Before you begin downloading or uploading an image file by using RCP, do these tasks:

Ensure that the workstation acting as the RCP server supports the remote shell (rsh).

Ensure that the switch has a route to the RCP server. The switch and the server must be in the same subnetwork if

you do not have a router to route traffic between subnets. Check connectivity to the RCP server by using the ping

command.

If you are accessing the switch through the console or a Telnet session and you do not have a valid username, make

sure that the current RCP username is the one that you want to use for the RCP download. You can enter the show

users privileged EXEC command to view the valid username. If you do not want to use this username, create a new

RCP username by using the ip rcmd remote-username username global configuration command to be used during

all archive operations. The new username is stored in NVRAM. If you are accessing the switch through a Telnet

session and you have a valid username, this username is used, and there is no need to set the RCP username. Include

the username in the archive download-sw or archive upload-sw privileged EXEC command if you want to specify

a username only for that operation.

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Working with Software Images

When you upload an image to the RCP to the server, it must be properly configured to accept the RCP write request

from the user on the switch. For UNIX systems, you must add an entry to the .rhosts file for the remote user on the

RCP server.

For example, suppose the switch contains these configuration lines:

hostname Switch1

ip rcmd remote-username User0

If the switch IP address translates to Switch1.company.com, the .rhosts file for User0 on the RCP server should

contain this line:

Switch1.company.com Switch1

For more information, see the documentation for your RCP server.

Downloading an Image File By Using RCP

You can download a new image file and replace or keep the current image.

Beginning in privileged EXEC mode, follow Steps 1 through 6 to download a new image from an RCP server and overwrite

the existing image. To keep the current image, go to Step 6.

Command

Purpose

Verify that the RCP server is properly configured by

referring to the Preparing to Download or Upload a

Configuration File By Using RCP, page 1049.

Log into the switch through the console port or a

Telnet session.

configure terminal

Enters global configuration mode.

This step is required only if you override the default remote

username (see Steps 4 and 5).

ip rcmd remote-username username

(Optional) Specifies the remote username.

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Working with Software Images

Command

Purpose

end

Returns to privileged EXEC mode.

archive download-sw /overwrite /reload

Downloads the image file from the RCP server to the switch,

rcp:[[[//[username@]location]/directory]/image-nam

and overwrite the current image.

e.tar]

The /overwrite option overwrites the software image in

flash memory with the downloaded image.

The /reload option reloads the system after

downloading the image unless the configuration has

been changed and not been saved.

For //username, specify the username. For the RCP

copy request to execute successfully, an account must

be defined on the network server for the remote

username.

For @location, specify the IP address of the RCP server.

For /directory/image-name.tar, specify the directory

(optional) and the image to download. Directory and

image names are case sensitive.

archive download-sw /leave-old-sw /reload

Downloads the image file from the RCP server to the switch,

rcp:[[[//[username@]location]/directory]/image-nam

and keep the current image.

e.tar]

The /leave-old-sw option keeps the old software

version after a download.

The /reload option reloads the system after

downloading the image unless the configuration has

been changed and not been saved.

For //username, specify the username. For the RCP

copy request to execute, an account must be defined on

the network server for the remote username.

For @location, specify the IP address of the RCP server.

For /directory]/image-name.tar, specify the directory

(optional) and the image to download. Directory and

image names are case sensitive.

The download algorithm verifies that the image is appropriate for the switch model and that enough DRAM is present, or

it aborts the process and reports an error. If you specify the /overwrite option, the download algorithm removes the

existing image on the flash device whether or not it is the same as the new one, downloads the new image, and then

reloads the software.

Note: If the flash device has sufficient space to hold two images and you want to overwrite one of these images with the

same version, you must specify the /overwrite option.

If you specify the /leave-old-sw, the existing files are not removed. If there is not enough room to install the new image

an keep the running image, the download process stops, and an error message is displayed.

The algorithm installs the downloaded image onto the system board flash device (flash:). The image is placed into a new

directory named with the software version string, and the BOOT environment variable is updated to point to the newly

installed image.

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Working with Software Images

If you kept the old software during the download process (you specified the /leave-old-sw keyword), you can remove

it by entering the delete /force /recursive filesystem:/file-url privileged EXEC command. For filesystem, use flash: for

the system board flash device. For file-url, enter the directory name of the old software image. All the files in the directory

and the directory are removed.

Caution: For the download and upload algorithms to operate properly, do not rename image names.

Uploading an Image File By Using RCP

You can upload an image from the switch to an RCP server. You can later download this image to the same switch or to

another switch of the same type.

The upload feature should be used only if the web management pages associated with the embedded device manager

have been installed with the existing image.

Beginning in privileged EXEC mode, follow these steps to upload an image to an RCP server:

Command

Purpose

Verify that the RCP server is properly configured by

referring to the Preparing to Download or Upload a

Configuration File By Using RCP, page 1049.

Log into the switch through the console port or a

Telnet session.

configure terminal

Enters global configuration mode.

This step is required only if you override the default remote

username (see Steps 4 and 5).

ip rcmd remote-username username

(Optional) Specifies the remote username.

end

Returns to privileged EXEC mode.

archive upload-sw

Uploads the currently running switch image to the RCP

rcp:[[[//[username@]location]/directory]/image-nam

server.

e.tar]

For //username, specify the username; for the RCP copy

request to execute, an account must be defined on the

network server for the remote username.

For @location, specify the IP address of the RCP server.

For /directory]/image-name.tar, specify the directory

(optional) and the name of the software image to be

uploaded. Directory and image names are case

sensitive.

The image-name.tar is the name of software image to

be stored on the server.

The archive upload-sw privileged EXEC command builds an image file on the server by uploading these files in order:

info, the Cisco IOS image, and the web management files. After these files are uploaded, the upload algorithm creates

the tar file format.

Caution: For the download and upload algorithms to operate properly, do not rename image names.

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Working with Software Images

Displaying Image Upgrade and Downgrade History

The show archive sw-upgrade history command displays the history of all software image upgrades and downgrades

performed on the device. This command displays the image name, version, upgrade method, and timeline for each

upgrade that is done through Auto Install, PnP, archive sw-download CLI, or HTTP methods. Manual upgrades done

through TFTP of tar files or binary files are not displayed.

Note: Only the first 100 upgrade or downgrade records are displayed.

To display the software image upgrade and downgrade history on a device, enter show archive sw- upgrade history in

privileged EXEC mode as shown in the following examples.

Archive download Example

SW1-2#sh arc sw-upgrade history all

SWITCH: 1

File_name

Version

Install Mode/Date

---------------------------------- ------- ------------------

ie5000-universalk9-mz.152-7.1.85k.E3.bin

152-7.1.85k.E3

download-sw/UTC Sun Apr 24 2011

ie5000-universalk9-mz.152-7.1.85k.E3.bin

152-7.1.85k.E3

download-sw/UTC Sun Apr 24 2011

ie5000-universalk9-mz.152-7.1.85k.E3.bin

152-7.1.85k.E3

download-sw/UTC Sun Apr 24 2011

DNAC (PnP) Example

Switch#sh archive sw-upgrade history

File_name

Version

Install Mode/Date

---------------------------------- ------- ------------------

ie5000-universalk9-mz.152-7.68i.E3.bin

152-7.68i.E3

pnp/UTC Mon Jan 2 2006

ie5000-universalk9-mz.152-7.1.76i.E3.bin

152-7.1.76i.E3

pnp/UTC Mon Jan 2 2006

HTTP Example

Switch#sh archive sw-upgrade history

File_name

Version

Install Mode/Date

---------------------------------- ------- ------------------

ie5000-universalk9-mz.152-7.68i.E3.bin

152-7.68i.E3

http/UTC Mon Jan 2 2006

ie5000-universalk9-mz.152-7.1.76i.E3.bin

152-7.1.76i.E3

http/UTC Mon Jan 2 2006

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Configuring EtherChannels

Information About Configuring EtherChannels

This chapter describes how to configure EtherChannels on the switch. EtherChannel provides fault-tolerant high-speed

links between switches, routers, and servers. You can use it to increase the bandwidth between the wiring closets and

the data center, and you can deploy it anywhere in the network where bottlenecks are likely to occur. EtherChannel

provides automatic recovery for the loss of a link by redistributing the load across the remaining links. If a link fails,

EtherChannel redirects traffic from the failed link to the remaining links in the channel without intervention. This chapter

also describes how to configure link-state tracking.

EtherChannels

An EtherChannel consists of individual Ethernet links bundled into a single logical link as shown in Figure 110 on

page 1069.

Figure 110 Typical EtherChannel Configuration

Catalyst 8500

series switch

Gigabit EtherChannel

1000BASE-X

10/100

Switched

links

Workstations

The EtherChannel provides full-duplex bandwidth up 2 Gb/s (Gigabit EtherChannel) between your switch and another

switch or host. Each EtherChannel can consist of up to eight compatibly configured Ethernet ports.

The number of EtherChannels is limited to 10. For more information, see EtherChannel Configuration Guidelines,

page 1077.

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Configuring EtherChannels

Information About Configuring EtherChannels

You can configure an EtherChannel in one of these modes: Port Aggregation Protocol (PAgP), Link Aggregation Control

Protocol (LACP), or On. Configure both ends of the EtherChannel in the same mode:

When you configure one end of an EtherChannel in either PAgP or LACP mode, the system negotiates with the other

end of the channel to determine which ports should become active. Incompatible ports are put into an independent

state and continue to carry data traffic as would any other single link. The port configuration does not change, but

the port does not participate in the EtherChannel.

When you configure an EtherChannel in the on mode, no negotiations take place. The switch forces all compatible

ports to become active in the EtherChannel. The other end of the channel (on the other switch) must also be

configured in the on mode; otherwise, packet loss can occur.

If a link within an EtherChannel fails, traffic previously carried over that failed link moves to the remaining links within the

EtherChannel. If traps are enabled on the switch, a trap is sent for a failure that identifies the switch, the EtherChannel,

and the failed link. Inbound broadcast and multicast packets on one link in an EtherChannel are blocked from returning

on any other link of the EtherChannel.

Port-Channel Interfaces

When you create an EtherChannel, a port-channel logical interface is involved:

With Layer 2 ports, use the channel-group interface configuration command to dynamically create the port-channel

logical interface.

You also can use the interface port-channel port-channel-number global configuration command to manually

create the port-channel logical interface, but then you must use the channel-group channel-group-number

command to bind the logical interface to a physical port. The channel-group-number can be the same as the

port-channel-number, or you can use a new number. If you use a new number, the channel-group command

dynamically creates a new port channel.

With Layer 3 ports, you should manually create the logical interface by using the interface port-channel global

configuration command followed by the no switchport interface configuration command. Then you manually assign

an interface to the EtherChannel by using the channel-group interface configuration command.

For both Layer 2 and Layer 3 ports, the channel-group command binds the physical port and the logical interface

together as shown in Figure 111 on page 1071.

Each EtherChannel has a port-channel logical interface numbered from 1 to 10. This port-channel interface number

corresponds to the one specified with the channel-group interface configuration command.

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Information About Configuring EtherChannels

Figure 111 Relationship of Physical Ports, Logical Port Channels, and Channel Groups

Logical

port-channel

Channel-group

binding

Physical ports

After you configure an EtherChannel, configuration changes applied to the port-channel interface apply to all the physical

ports assigned to the port-channel interface. Configuration changes applied to the physical port affect only the port

where you apply the configuration. To change the parameters of all ports in an EtherChannel, apply configuration

commands to the port-channel interface, for example, spanning-tree commands or commands to configure a Layer 2

EtherChannel as a trunk.

Port Aggregation Protocol

The Port Aggregation Protocol (PAgP) is a Cisco-proprietary protocol that can be run only on Cisco switches and on

those switches licensed by vendors to support PAgP. PAgP facilitates the automatic creation of EtherChannels by

exchanging PAgP packets between Ethernet ports.

By using PAgP, the switch learns the identity of partners capable of supporting PAgP and the capabilities of each port. It

then dynamically groups similarly configured ports into a single logical link (channel or aggregate port). Similarly

configured ports are grouped based on hardware, administrative, and port parameter constraints. For example, PAgP

groups the ports with the same speed, duplex mode, native VLAN, VLAN range, and trunking status and type. After

grouping the links into an EtherChannel, PAgP adds the group to the spanning tree as a single switch port.

PAgP Modes

Table 70User-Configurable EtherChannel PAgP Modes, page 1072 shows the user-configurable EtherChannel PAgP

modes for the channel-group interface configuration command.

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Information About Configuring EtherChannels

Table 70

User-Configurable EtherChannel PAgP Modes

Mode

Description

auto

Places a port into a passive negotiating state, in which the port responds to PAgP packets it receives but

does not start PAgP packet negotiation. This setting minimizes the transmission of PAgP packets.

desirable

Places a port into an active negotiating state, in which the port starts negotiations with other ports by

sending PAgP packets.

Switch ports exchange PAgP packets only with partner ports configured in the auto or desirable modes. Ports

configured in the on mode do not exchange PAgP packets.

Both the auto and desirable modes enable ports to negotiate with partner ports to form an EtherChannel based on

criteria such as port speed and, for Layer 2 EtherChannels, trunking state and VLAN numbers.

Ports can form an EtherChannel when they are in different PAgP modes as long as the modes are compatible. For

example:

A port in the desirable mode can form an EtherChannel with another port that is in the desirable or auto mode.

A port in the auto mode can form an EtherChannel with another port in the desirable mode.

A port in the auto mode cannot form an EtherChannel with another port that is also in the auto mode because neither

port starts PAgP negotiation.

If your switch is connected to a partner that is PAgP-capable, you can configure the switch port for nonsilent operation

by using the non-silent keyword. If you do not Specifies non-silent with the auto or desirable mode, silent mode is

assumed.

Use the silent mode when the switch is connected to a device that is not PAgP-capable and seldom, if ever, sends

packets. An example of a silent partner is a file server or a packet analyzer that is not generating traffic. In this case,

running PAgP on a physical port connected to a silent partner prevents that switch port from ever becoming operational.

However, the silent setting allows PAgP to operate, to attach the port to a channel group, and to use the port for

transmission.

PAgP Learn Method and Priority

Network devices are classified as PAgP physical learners or aggregate-port learners. A device is a physical learner if it

learns addresses by physical ports and directs transmissions based on that knowledge. A device is an aggregate-port

learner if it learns addresses by aggregate (logical) ports. The learn method must be configured the same at both ends

of the link.

When a device and its partner are both aggregate-port learners, they learn the address on the logical port-channel. The

device sends packets to the source by using any of the ports in the EtherChannel. With aggregate-port learning, it is not

important on which physical port the packet arrives.

PAgP cannot automatically detect when the partner device is a physical learner and when the local device is an

aggregate-port learner. Therefore, you must manually set the learning method on the local device to learn addresses by

physical ports. You also must set the load-distribution method to source-based distribution, so that any given source

MAC address is always sent on the same physical port.

You also can configure a single port within the group for all transmissions and use other ports for hot standby. The unused

ports in the group can be swapped into operation in just a few seconds if the selected single port loses hardware-signal

detection. You can configure which port is always selected for packet transmission by changing its priority with the pagp

port-priority interface configuration command. The higher the priority, the more likely that the port will be selected.

Note: The switch supports address learning only on aggregate ports even though the physical-port keyword is provided

in the CLI. The pagp learn-method command and the pagp port-priority command have no effect on the switch

hardware, but they are required for PAgP interoperability with devices that only support address learning by physical

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Configuring EtherChannels

Information About Configuring EtherChannels

ports.

When the link partner of the switch is a physical learner (such as a Catalyst 1900 series switch), we recommend that you

configure the switch as a physical-port learner by using the pagp learn-method physical-port interface configuration

command. Set the load-distribution method based on the source MAC address by using the port-channel load-balance

src-mac global configuration command. The switch then sends packets to the Catalyst 1900 switch using the same port

in the EtherChannel from which it learned the source address. Only use the pagp learn-method command in this

situation.

PAgP Interaction with Virtual Switches and Dual-Active Detection

A virtual switch can be two or more core switches connected by virtual switch links (VSLs) that carry control and data

traffic between them. One of the switches is in active mode. The others are in standby mode. For redundancy, remote

switches, are connected to the virtual switch by remote satellite links (RSLs).

If the VSL between two switches fails, one switch does not know the status of the other. Both switches could change to

the active mode, causing a dual-active situation in the network with duplicate configurations (including duplicate IP

addresses and bridge identifiers). The network might go down.

To prevent a dual-active situation, the core switches send PAgP protocol data units (PDUs) through the RSLs to the

remote switches. The PAgP PDUs identify the active switch, and the remote switches forward the PDUs to core switches

so that the core switches are in sync. If the active switch fails or resets, the standby switch takes over as the active switch.

If the VSL goes down, one core switch knows the status of the other and does not change state.

PAgP Interaction with Other Features

The Dynamic Trunking Protocol (DTP) and the Cisco Discovery Protocol (CDP) send and receive packets over the physical

ports in the EtherChannel. Trunk ports send and receive PAgP protocol data units (PDUs) on the lowest numbered VLAN.

In Layer 2 EtherChannels, the first port in the channel that comes up provides its MAC address to the EtherChannel. If

this port is removed from the bundle, one of the remaining ports in the bundle provides its MAC address to the

EtherChannel.

PAgP sends and receives PAgP PDUs only from ports that are up and have PAgP enabled for the auto or desirable mode.

Link Aggregation Control Protocol

The LACP is defined in IEEE 802.3ad and enables Cisco switches to manage Ethernet channels between switches that

conform to the IEEE 802.3ad protocol. LACP facilitates the automatic creation of EtherChannels by exchanging LACP

packets between Ethernet ports.

By using LACP, the switch learns the identity of partners capable of supporting LACP and the capabilities of each port.

It then dynamically groups similarly configured ports into a single logical link (channel or aggregate port). Similarly

configured ports are grouped based on hardware, administrative, and port parameter constraints. For example, LACP

groups the ports with the same speed, duplex mode, native VLAN, VLAN range, and trunking status and type. After

grouping the links into an EtherChannel, LACP adds the group to the spanning tree as a single switch port.

LACP Modes

Table 2 shows the user-configurable EtherChannel LACP modes for the channel-group interface configuration

command.

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Configuring EtherChannels

Information About Configuring EtherChannels

Table 71

User-Configurable EtherChannel LACP Modes

Mode

Description

active

Places a port into an active negotiating state in which the port starts negotiations with other ports by

sending LACP packets.

passive

Places a port into a passive negotiating state in which the port responds to LACP packets that it receives,

but does not start LACP packet negotiation. This setting minimizes the transmission of LACP packets.

Both the active and passive LACP modes enable ports to negotiate with partner ports to an EtherChannel based on

criteria such as port speed and, for Layer 2 EtherChannels, trunking state and VLAN numbers.

Ports can form an EtherChannel when they are in different LACP modes as long as the modes are compatible. For

example:

A port in the active mode can form an EtherChannel with another port that is in the active or passive mode.

A port in the passive mode cannot form an EtherChannel with another port that is also in the passive mode because

neither port starts LACP negotiation.

LACP Hot-Standby Ports

When enabled, LACP tries to configure the maximum number of LACP-compatible ports in a channel, up to a maximum

of 16 ports. Only eight LACP links can be active at one time. The software places any additional links in a hot-standby

mode. If one of the active links becomes inactive, a link that is in the hot-standby mode becomes active in its place.

If you configure more than eight links for an EtherChannel group, the software automatically decides which of the

hot-standby ports to make active based on the LACP priority. To every link between systems that operate LACP, the

software assigns a unique priority made up of these elements (in priority order):

LACP system priority

System ID (the switch MAC address)

LACP port priority

Port number

In priority comparisons, numerically lower values have higher priority. The priority decides which ports should be put in

standby mode when there is a hardware limitation that prevents all compatible ports from aggregating.

Determining which ports are active and which are hot standby is a two-step procedure. First the system with a

numerically lower system priority and system-id is placed in charge of the decision. Next, that system decides which

ports are active and which are hot standby, based on its values for port priority and port number. The port-priority and

port-number values for the other system are not used.

You can change the default values of the LACP system priority and the LACP port priority to affect how the software

selects active and standby links.

By default, all ports use the same port priority. If the local system has a lower value for the system priority and the system

ID than the remote system, you can affect which of the hot-standby links become active first by changing the port priority

of LACP EtherChannel ports to a lower value than the default. The hot-standby ports that have lower port numbers

become active in the channel first. You can use the show etherchannel summary privileged EXEC command to see

which ports are in the hot-standby mode (denoted with an H port-state flag).

If LACP is not able to aggregate all the ports that are compatible (for example, the remote system might have more

restrictive hardware limitations), all the ports that cannot be actively included in the EtherChannel are put in the

hot-standby state and are used only if one of the channeled ports fails.

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Configuring EtherChannels

Information About Configuring EtherChannels

LACP Interaction with Other Features

The DTP and the CDP send and receive packets over the physical ports in the EtherChannel. Trunk ports send and receive

LACP PDUs on the lowest numbered VLAN.

In Layer 2 EtherChannels, the first port in the channel that comes up provides its MAC address to the EtherChannel. If

this port is removed from the bundle, one of the remaining ports in the bundle provides its MAC address to the

EtherChannel.

LACP sends and receives LACP PDUs only from ports that are up and have LACP enabled for the active or passive mode.

EtherChannel On Mode

EtherChannel on mode can be used to manually configure an EtherChannel. The on mode forces a port to join an

EtherChannel without negotiations. The on mode can be useful if the remote device does not support PAgP or LACP. In

the on mode, a usable EtherChannel exists only when the switches at both ends of the link are configured in the on mode.

Ports that are configured in the on mode in the same channel group must have compatible port characteristics, such as

speed and duplex. Ports that are not compatible are suspended, even though they are configured in the on mode.

Caution: You should use care when using the on mode. This is a manual configuration, and ports on both ends of the

EtherChannel must have the same configuration. If the group is misconfigured, packet loss or spanning-tree loops

can occur.

Load Balancing and Forwarding Methods

EtherChannel balances the traffic load across the links in a channel by reducing part of the binary pattern formed from

the addresses in the frame to a numerical value that selects one of the links in the channel. EtherChannel load balancing

can use MAC addresses or IP addresses, source or destination addresses, or both source and destination addresses.

The selected mode applies to all EtherChannels configured on the switch. You configure the load balancing and

forwarding method by using the port-channel load-balance global configuration command.

With source-MAC address forwarding, when packets are forwarded to an EtherChannel, they are distributed across the

ports in the channel based on the source-MAC address of the incoming packet. Therefore, to provide load balancing,

packets from different hosts use different ports in the channel, but packets from the same host use the same port in the

channel.

With destination-MAC address forwarding, when packets are forwarded to an EtherChannel, they are distributed across

the ports in the channel based on the destination host’s MAC address of the incoming packet. Therefore, packets to the

same destination are forwarded over the same port, and packets to a different destination are sent on a different port in

the channel.

With source-and-destination MAC address forwarding, when packets are forwarded to an EtherChannel, they are

distributed across the ports in the channel based on both the source and destination MAC addresses. This forwarding

method, a combination source-MAC and destination-MAC address forwarding methods of load distribution, can be used

if it is not clear whether source-MAC or destination-MAC address forwarding is better suited on a particular switch. With

source-and-destination MAC-address forwarding, packets sent from host A to host B, host A to host C, and host C to

host B could all use different ports in the channel.

With source-IP address-based forwarding, when packets are forwarded to an EtherChannel, they are distributed across

the ports in the EtherChannel based on the source-IP address of the incoming packet. Therefore, to provide

load-balancing, packets from different IP addresses use different ports in the channel, but packets from the same IP

address use the same port in the channel.

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Configuring EtherChannels

Information About Configuring EtherChannels

With destination-IP address-based forwarding, when packets are forwarded to an EtherChannel, they are distributed

across the ports in the EtherChannel based on the destination-IP address of the incoming packet. Therefore, to provide

load-balancing, packets from the same IP source address sent to different IP destination addresses could be sent on

different ports in the channel. But packets sent from different source IP addresses to the same destination IP address

are always sent on the same port in the channel.

With source-and-destination IP address-based forwarding, packets are sent to an EtherChannel and distributed across

the EtherChannel ports, based on both the source and destination IP addresses of the incoming packet. This forwarding

method, a combination of source-IP and destination-IP address-based forwarding, can be used if it is not clear whether

source-IP or destination-IP address-based forwarding is better suited on a particular switch. In this method, packets

sent from the IP address A to IP address B, from IP address A to IP address C, and from IP address C to IP address B

could all use different ports in the channel.

Different load-balancing methods have different advantages, and the choice of a particular load-balancing method

should be based on the position of the switch in the network and the kind of traffic that needs to be load-distributed. In

Figure 112 on page 1077, an EtherChannel from a switch that is aggregating data from four workstations communicates

with a router. Because the router is a single-MAC-address device, source-based forwarding on the switch EtherChannel

ensures that the switch uses all available bandwidth to the router. The router is configured for destination-based

forwarding because the large number of workstations ensures that the traffic is evenly distributed from the router

EtherChannel.

Use the option that provides the greatest variety in your configuration. For example, if the traffic on a channel is only

going to a single MAC address, using the destination-MAC address always chooses the same link in the channel. Using

source addresses or IP addresses might result in better load balancing.

1076

Configuring EtherChannels

Information About Configuring EtherChannels

Figure 112 Load Distribution and Forwarding Methods

Switch with

source-based

forwarding enabled

EtherChannel

Cisco router

with destination-based

forwarding enabled

Default EtherChannel Settings

Feature

Default Setting

Channel groups

None assigned.

Port-channel logical interface

None defined.

PAgP mode

No default.

PAgP learn method

Aggregate-port learning on all ports.

PAgP priority

128 on all ports.

LACP mode

No default.

LACP learn method

Aggregate-port learning on all ports.

LACP port priority

32768 on all ports.

LACP system priority

32768.

LACP system ID

LACP system priority and the switch MAC address.

Load balancing

Load distribution on the switch is based on the source-MAC

address of the incoming packet.

EtherChannel Configuration Guidelines

If improperly configured, some EtherChannel ports are automatically disabled to avoid network loops and other problems.

Follow these guidelines to avoid configuration problems:

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Configuring EtherChannels

Information About Configuring EtherChannels

Do not try to configure more than 6 EtherChannels on the switch.

Configure a PAgP EtherChannel with up to ten Ethernet ports of the same type.

Configure a LACP EtherChannel with up to16 Ethernet ports of the same type. Up to eight ports can be active, and

up to eight ports can be in standby mode.

Configure all ports in an EtherChannel to operate at the same speeds and duplex modes.

Enable all ports in an EtherChannel. A port in an EtherChannel that is disabled by using the shutdown interface

configuration command is treated as a link failure, and its traffic is transferred to one of the remaining ports in the

EtherChannel.

When a group is first created, all ports follow the parameters set for the first port to be added to the group. If you

change the configuration of one of these parameters, you must also make the changes to all ports in the group:

— Allowed-VLAN list

— Spanning-tree path cost for each VLAN

— Spanning-tree port priority for each VLAN

— Spanning-tree Port Fast setting

Do not configure a port to be a member of more than one EtherChannel group.

Do not configure an EtherChannel in both the PAgP and LACP modes. EtherChannel groups running PAgP and LACP

can coexist on the same switch. Individual EtherChannel groups can run either PAgP or LACP, but they cannot

interoperate.

Do not configure a Switched Port Analyzer (SPAN) destination port as part of an EtherChannel.

Do not configure a secure port as part of an EtherChannel or the reverse.

Do not configure a private-VLAN port as part of an EtherChannel.

Do not configure a port that is an active or a not-yet-active member of an EtherChannel as an IEEE 802.1x port. If

you try to enable IEEE 802.1x on an EtherChannel port, an error message appears, and IEEE 802.1x is not enabled.

If EtherChannels are configured on switch interfaces, remove the EtherChannel configuration from the interfaces

before globally enabling IEEE 802.1x on a switch by using the dot1x system-auth-control global configuration

command.

For Layer 2 EtherChannels:

— Assign all ports in the EtherChannel to the same VLAN, or configure them as trunks. Ports with different native

VLANs cannot form an EtherChannel.

— If you configure an EtherChannel from trunk ports, verify that the trunking mode (ISL or IEEE 802.1Q) is the same

on all the trunks. Inconsistent trunk modes on EtherChannel ports can have unexpected results.

— An EtherChannel supports the same allowed range of VLANs on all the ports in a trunking Layer 2 EtherChannel.

If the allowed range of VLANs is not the same, the ports do not form an EtherChannel even when PAgP is set to

the auto or desirable mode.

— Ports with different spanning-tree path costs can form an EtherChannel if they are otherwise compatibly

configured. Setting different spanning-tree path costs does not, by itself, make ports incompatible for the

formation of an EtherChannel.

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Configuring EtherChannels

How to Configure EtherChannels

Note: After you configure an EtherChannel, configuration changes applied to the port-channel interface apply to all the

physical ports assigned to the port-channel interface, and configuration changes applied to the physical port affect only

the port where you apply the configuration.

Configuring Layer 2 EtherChannels

You configure Layer 2 EtherChannels by assigning ports to a channel group with the channel-group interface

configuration command. This command automatically creates the port-channel logical interface.

This required task explains how to configure a Layer 2 Ethernet port to a Layer 2 EtherChannel.

Command

Purpose

configure terminal

Enters global configuration mode.

interface interface-id

Specifies a physical port, and enter interface configuration

mode.

Valid interfaces include physical ports.

For a PAgP EtherChannel, you can configure up to eight ports of

the same type and speed for the same group.

For a LACP EtherChannel, you can configure up to 16 Ethernet

ports of the same type. Up to eight ports can be active, and up

to eight ports can be in standby mode.

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Configuring EtherChannels

How to Configure EtherChannels

Command

Purpose

switchport mode {access | trunk}

Assigns all ports as static-access ports in the same VLAN, or

configures them as trunks.

switchport access vlan vlan-id

If you configure the port as a static-access port, assign it to only

one VLAN. The range is 1 to 4096.

channel-group channel-group-number mode

Assigns the port to a channel group, and specifies the PAgP or

{auto [non-silent] | desirable [non-silent] | on}

the LACP mode.

| {active | passive}

For channel-group-number, the range is 1 to 10.

For mode, select one of these keywords:

auto—Enables PAgP only if a PAgP device is detected. It

places the port into a passive negotiating state, in which the

port responds to PAgP packets it receives but does not start

PAgP packet negotiation.

desirable—Unconditionally enables PAgP. It places the port

into an active negotiating state, in which the port starts

negotiations with other ports by sending PAgP packets.

on—Forces the port to channel without PAgP or LACP. In the

on mode, an EtherChannel exists only when a port group in

the on mode is connected to another port group in the on

mode.

non-silent—(Optional) If your switch is connected to a

partner that is PAgP-capable, configure the switch port for

nonsilent operation when the port is in the auto or desirable

mode. If you do not Specifies non-silent, silent is assumed.

The silent setting is for connections to file servers or packet

analyzers. This setting allows PAgP to operate, to attach the

port to a channel group, and to use the port for transmission.

active—Enables LACP only if a LACP device is detected. It

places the port into an active negotiating state in which the

port starts negotiations with other ports by sending LACP

packets.

passive—Enables LACP on the port and places it into a

passive negotiating state in which the port responds to

LACP packets that it receives, but does not start LACP

packet negotiation.

For information on compatible modes for the switch and its

partner, see PAgP Modes, page 1071 and the LACP Modes,

page 1073.

end

Returns to privileged EXEC mode.

Configuring EtherChannel Load Balancing

This task is optional.

1080

Configuring EtherChannels

How to Configure EtherChannels

Command

Purpose

configure terminal

Enters global configuration mode.

port-channel load-balance {dst-ip | dst-mac |

Configures an EtherChannel load-balancing method.

src-dst-ip | src-dst-mac | src-ip | src-mac}

The default is src-mac.

Select one of these load-distribution methods:

dst-ip—Specifies the destination-host IP address.

dst-mac—Specifies the destination-host MAC address of

the incoming packet.

src-dst-ip— Specifies the source-and-destination host-IP

address.

src-dst-mac—Specifies the source-and-destination

host-MAC address.

src-ip— Specifies the source-host IP address.

src-mac—Specifies the source-MAC address of the

incoming packet.

end

Returns to privileged EXEC mode.

Configuring the PAgP Learn Method and Priority

This task is optional.

Command

Purpose

configure terminal

Enters global configuration mode.

interface interface-id

Specifies the port for transmission, and enter interface

configuration mode.

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Configuring EtherChannels

How to Configure EtherChannels

Command

Purpose

pagp learn-method physical-port

Selects the PAgP learning method.

By default, aggregation-port learning is selected, which means

the switch sends packets to the source by using any of the ports

in the EtherChannel. With aggregate-port learning, it is not

important on which physical port the packet arrives.

Select physical-port to connect with another switch that is a

physical learner. Make sure to configure the port-channel

load-balance global configuration command to src-mac as

described in the Configuring EtherChannel Load Balancing,

page 1080.

The learning method must be configured the same at both ends

of the link.

pagp port-priority priority

Assigns a priority so that the selected port is chosen for packet

transmission.

For priority, the range is 0 to 255. The default is 128. The higher

the priority, the more likely that the port will be used for PAgP

transmission.

end

Returns to privileged EXEC mode.

Configuring the LACP Hot-Standby Ports

This task is optional.

Command

Purpose

configure terminal

Enters global configuration mode.

lacp system-priority priority

Configures the LACP system priority.

For priority, the range is 1 to 65535. The default is 32768.

The lower the value, the higher the system priority.

interface interface-id

Specifies the port to be configured, and enters interface

configuration mode.

lacp port-priority priority

Configures the LACP port priority.

For priority, the range is 1 to 65535. The default is 32768. The

lower the value, the more likely that the port will be used for

LACP transmission.

end

Returns to privileged EXEC mode.

1082

Configuring EtherChannels

Monitoring and Maintaining EtherChannels

Command

Purpose

show etherchannel [channel-group-number

Displays EtherChannel information in a brief,

{detail | port | port-channel | protocol |

detailed, and one-line summary form. Also

summary}] {detail | load-balance | port |

displays the load-balance or frame-distribution

port-channel | protocol | summary}

scheme, port, port-channel, and protocol

information.

show pagp [channel-group-number] {counters |

Displays PAgP information such as traffic

internal | neighbor}

information, the internal PAgP configuration, and

neighbor information.

show pagp [channel-group-number]

Displays the dual-active detection status.

dual-active

show lacp [channel-group-number] {counters |

Displays LACP information such as traffic

internal | neighbor}

information, the internal LACP configuration, and

neighbor information.

Configuration Examples for Configuring EtherChannels

Configuring EtherChannels: Examples

This example shows how to configure an EtherChannel and assign two ports as static-access ports in VLAN 10 to

channel 5 with the PAgP mode desirable:

Switch# configure terminal

Switch(config)# interface range GigabitEthernet1/17 -2

Switch(config-if-range)# switchport mode access

Switch(config-if-range)# switchport access vlan 10

Switch(config-if-range)# channel-group 5 mode desirable non-silent

Switch(config-if-range)# end

This example shows how to configure an EtherChannel and assign two ports as static-access ports in VLAN 10 to

channel 5 with the LACP mode active:

Switch# configure terminal

Switch(config)# interface range GigabitEthernet1/17 -2

Switch(config-if-range)# switchport mode access

Switch(config-if-range)# switchport access vlan 10

Switch(config-if-range)# channel-group 5 mode active

Switch(config-if-range)# end

Additional References

The following sections provide references related to switch administration:

1083

Configuring EtherChannels

Additional References

Cisco Industrial Ethernet 4000, 4010 and 5000 Switch Software. Configuration Guide (2022) - page 38