HP ProCurve J8766A Release Note page 33

Changing the Keepalive Interval. By default, ports enabled for UDLD send a link health-check
packet once every 5 seconds. You can change the interval to a value from 10 – 100 deciseconds, where
10 is 1 second, 11 is 1.1 seconds, and so on. For example, to change the packet interval to seven
seconds, enter the following command at the global configuration level:
ProCurve(config)# link-keepalive interval 70
Changing the Keepalive Retries. By default, a port waits five seconds to receive a health-check
reply packet from the port at the other end of the link. If the port does not receive a reply, the port
tries four more times by sending up to four more health-check packets. If the port still does not receive
a reply after the maximum number of retries, the port goes down.
You can change the maximum number of keepalive attempts to a value from 3 – 10. For example, to
change the maximum number of attempts to 4, enter the following command at the global configu-
ration level:
ProCurve(config)# link-keepalive retries 4
Configuring UDLD for Tagged Ports. The default implementation of UDLD sends the UDLD
control packets untagged, even across tagged ports. If an untagged UDLD packet is received by a
non-ProCurve switch, that switch may reject the packet. To avoid such an occurrence, you can
configure ports to send out UDLD control packets that are tagged with a specified VLAN.
To enable ports to receive and send UDLD control packets tagged with a specific VLAN ID, enter a
command such as the following at the interface configuration level:
ProCurve(config)#interface l link-keepalive vlan 22
Notes
■ You must configure the same VLANs that will be used for UDLD on all devices across the
network; otherwise, the UDLD link cannot be maintained.
If a VLAN ID is not specified, then UDLD control packets are sent out of the port as untagged
■
packets.
To re-assign a VLAN ID, re-enter the command with the new VLAN ID number. The new
■
command will overwrite the previous command setting.
When configuring UDLD for tagged ports, you may receive a warning message if there are
■
any inconsistencies with the port's VLAN configuration (see page 30 for potential problems).
Enhancements
Release L.10.07 Enhancements
27