Allied Telesis AlliedWare Plus Operating System Version 5.4.4C (x310-26FT,x310-26FP,x310-50FT,x310-50FP) - Manual (Page 59)

Getting Started
Software Reference for x310 Series Switches
C613-50046-01 REV A AlliedWare Plus TM Operating System - Version 5.4.4C 1.35
Continuous Reboot Prevention
Occasionally, due to network conditions or to recover from a software failure, the recovery
mechanism of the switch is to reboot to resume normal operation. Provided the same
error condition does not recur within a short period of time this is acceptable behavior.
However, if the error condition repeatedly occurs within a short time period, the switch
will go into a cycle of continuous reboots, causing network problems.
Although a switch continuously rebooting will come to the attention of a network
administrator who can then resolve the issue, it is likely that in the meantime network
problems have arisen. For example, a broadcast storm due to STP becoming unstable and
trying to continually reconverge could cause the switch to reboot continuously.
In a VCStack situation, a continually rebooting switch will destabilize the stack and may
cause the master and member devices to continually swap roles as they both reboot. This
can seriously affect the network, because both devices will become too busy rebooting
and forming the stack to forward traffic.
The continuous reboot prevention feature, enabled with the continuous-reboot-
prevention command on page 8.11 , allows the user to configure a switch to stop
rebooting if the device gets into a cycle of continuous rebooting. The user can configure
the time period, the maximum number of times the switch can reboot within the specified
time period, referred to as the threshold, and the action to take if the threshold is
exceeded.
There are three actions you can specify:
■ linkdown
The reboot procedure continues and all switch ports and stack ports stay link down.
This is the default action.
■ logonly
The reboot procedure continues normally.
■ stopreboot
The reboot procedure stops and the user is prompted to enter the key ”c” via the CLI.
Normal reboot procedure then continues.
Note that when the continuous reboot prevention feature is enabled on the switch, user
initiated reboots via the CLI and software version auto-synchronization reboots (VCStack
implementation) are not counted toward the threshold value.
The continuous reboot prevention feature is disabled by default. To enable the feature,
enter the following commands:
Unless the period, threshold and action parameter values are explicitly set, the defaults
are used:
■ period - 600 seconds
■ threshold - 1 reboot event
■ action - linkdown
awplus# configure terminal
awplus(config)# continuous-reboot-prevention enable