Troubleshooting guide

Configuring Reboot Loop Protection
Advanced System Diagnostics and Troubleshooting Guide 43
Configuring Reboot Loop Protection
Reboot loop protection prevents a failure that persists across a reboot from putting the switch into an
endless cycle of reboots. Reboot loop protection is helpful to increase network stability in the event that
some systematic problem is causing the watchdog timer to expire or a software exception to be
triggered repeatedly. You can configure a reboot threshold and a history timer. If more than the
threshold number of automatic reboots occurs within the history timer interval, the system boots into
minimal mode with all ports disabled. For more information about minimal mode, see
Appendix A.
NOTE
This capability can be helpful when there are two systems in a redundant configuration: If the reboot
loop happens, the rebooting system will end up offline and its redundant peer will take over until the
switch stuck in the reboot loop has been fixed.
In a non-redundant configuration, the use of this feature might result in the lone switch being taken
offline permanently.
Related Commands
configure reboot-loop-protection threshold
show switch
show configuration
Configuring Reboot Loop Protection
To configure reboot loop protection, use the following command:
configure reboot-loop-protection threshold <time-interval> <count>
where:
• By default, the reboot loop protection feature is disabled. If you enable the feature, the
recommended period for the time-interval threshold is 10 minutes.
• Specifying a time interval of 0 minutes disables the feature; specifying any other value enables it.
• If you specify a value for time-interval, but not for count, the default value for count is 3 reboots.
• If you reboot the switch manually, or use either the run msm-failover command or the
show configuration command, the time interval and count are both reset to 0.
• To view the current settings, use the show switch or show configuration commands.
• The reboot loop protection settings are stored in the switch memory, but are not saved in the switch
configuration. In a BlackDiamond switch equipped with redundant MSM64i modules, the
synchronize command does transfer the reboot loop protection settings to the synchronized
MSM64i.
time-interval The time period, in minutes, during which the switch is permitted to reboot the number
of times specified in count, before entering minimal mode. The period is a number in
the range from 0 to 255 minutes. The recommended setting is 10 minutes.
count The number of reboots within the period specified as time-interval. The count is a
number in the range from 1 reboot to 7 reboots.