Disabling Uplink Failure Detection; Configuring The Defer Timer - Dell PowerEdge M IO Aggregator Command Reference Manual

Disabling Uplink Failure Detection

In some network topologies, you may prefer that downstream links on an Aggregator remain opera-
tionally up and continue transmitting traffic without being automatically disabled when connectivity to
an upstream switch/router goes down.
When UFD is enabled and the upstream connectivity on LAG 128 fails, downstream links are also dis-
abled. To avoid this behavior, you can disable the UFD link tracking provided by uplink-state group 1,
which associates the upstream connectivity of LAG 128 with downstream connectivity on Aggregator
ports.
To disable UFD link-tracking, enter the
mode.
Task
Enter the uplink-state-group configuration level.
Disable the UFD link-tracking configuration.
To re-enable the UFD link-tracking configuration, enter the
configuration mode, save the running configuration to startup-config, and reload the switch.

Configuring the Defer Timer

You can configure UFD link tracking to use a defer timer before disabling downstream links when
LAG 128, which provides connectivity to upstream devices, goes down.
Use the
defer-timer
vents unwanted flapping of downstream ports when the uplink port channel goes down and comes up.
You must save the new UFD setting in the startup configuration and reload the switch to activate the
timer.
Task
Enter the uplink-state-group configuration level.
Specify the time (in seconds) to wait for the upstream
port channel (LAG 128) to come back up before server
ports are brought down. Range: 1-120. There is no
default timer.
no enable
command in uplink-state-group-1 configuration mode to configure a timer that pre-
command in uplink-state-group-1 configuration
Command
uplink-state group 1
no enable
command in uplink-state-group-1
enable
Command
uplink-state group 1
defer-timer seconds
Command Mode
CONFIGURATION
UPLINK-STATE-GROUP
Command Mode
CONFIGURATION
UPLINK-STATE-GROUP
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