Date created: Friday, June 29, 2018 9:14:24 AM. Last modified: Friday, June 29, 2018 9:17:23 AM

6500/7600 Conf Register

Sometimes changes aren't synchronised to the standby SUP, e.g. the new IOS image file to boot. If this happens a trick is to go to conf t, change the conf register to something else, confreg 0x2142 (this is the confreg to boot a blank config), then quit, save, then conf t again, confreg 0x2102 (back to the normal value), then exit and then save again. Changing the conf register can sometimes force a sync from master SUP to backup if it's not syncing.

There is two boot registers on the 6500 supervisor card, one on the Switch Processor and one on the Route Processor. The SP boots first and then hands off to the RP. Under normal circumstances "show boot" will show the boot variables for the RP "remote command switch show boot" must be used to show the boot variables for the SP.

Sometimes changes to the device configuration and/or the config registers aren't synchronised to the standby SUP, e.g. a new IOS image file to boot.

If this happens a trick is to go into conf t, change the conf register to something else, confreg 0x2142 (this is the confreg to boot a blank config), then quit, save, then conf t again, confreg 0x2102 (the normal value), then exit and then save again.

The combination of a changing the conf register and writing the config can sometimes force a sync from master SUP to backup SUP if it's not syncing the device config or config register.

Check all values using the following commands:
show bootvar
remote command switch show boot
remote command standby-rp show bootvar
remote command standby-sp show bootvar