This article describes how to change speed, duplex, and auto-negotiation on a network interface in XenServer.

Requirements

Console access required, if reconfiguring the management interface.

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Instructions

To modify network speed and duplexing, complete the following procedure:

1. Run the following command to find the physical interface where you need to apply the settings:
   # xe pif-list host-uuid=<host_uuid> 
   Note: xe pif-list command lists all the physical interfaces from all hosts in the pool. It is required to filter the interfaces by “host-uuid” if you need to find the right interface.

2. Review current physical interface settings:
   # xe pif-list uuid=<UUID of physical interface> params=all

3. Run the following command to set speed, duplex, and auto-negotiation:
   # xe pif-param-set uuid=<UUID of physical interface> other-config:ethtool-autoneg=off other-config:ethtool-speed=1000 other-config:ethtool-duplex=full
   Note: Turn off auto-negotiation before setting the speed manually.

4. Apply the setting on the interface. 

5. Unplug and plug the physical interface:
   Note: You do not need to unplug and plug the interface as follows. If you are unable to unplug the interface and skip the following step, then the settings will be applied after the next reboot.
   # xe pif-unplug uuid=<UUID of physical interface>
   # xe pif-plug uuid=<UUID of physical interface>
   Or
   Restart the host:
   # xe host-reboot host=<hostname>

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This article describes how to modify network speed and duplex on a network interface.

Modifying duplex, speed, and auto-negotiation can be made with ethtool on the fly; the change is not persistent across reboot.

Show current settings:
# ethtool eth0

Configure duplex, speed, and autonegotiation manually:
# ethtool -s eth0 speed 100 duplex true autoneg off

Man page for the ethtool:
# man ethtool

Note: For more information, refer section ethtool settings in the XenServer Software Development Kit Guide.