Description

This article provides a procedure to recover from a missed step in the upgrade procedure to SCBE in mx960

Due to configuration steps missed in SCBE upgradation procedure, all 6 planes shows active with SCBE. It should show  2 planes as a spare  and 4 planes as active with SCBE.

Symptoms

6 planes shows active with SCBE after upgrading from SCBE.

lab> show chassis fabric summary
Plane State Uptime
0 Online 1 day, 5 hours, 10 minutes, 46 seconds
1 Online 1 day, 5 hours, 10 minutes, 36 seconds
2 Online 1 day, 5 hours, 16 minutes, 27 seconds
3 Online 1 day, 5 hours, 16 minutes, 27 seconds
4 Online 1 day, 5 hours, 16 minutes, 26 seconds
5 Online 1 day, 5 hours, 16 minutes, 26 seconds


lab> show chassis fabric mode
Fabric Operating Mode :
Increased Bandwidth     >>>>>>>>>>>>>>>>>>>>

Solution

This behaviour is seen when  "set chassis state cb-upgrade off " command is missed in the upgradation procedure as mentioned in:
http://www.juniper.net/techpubs/en_US/release-independent/junos/topics/task/installation/scb-mxseries-mx960-upgrading-operational.html

We can recover from this issue in either step (1) or (2) according to the configuration.

1.  Issue "restart chassis-control " if GRES disabled and  after this system  shoudl detect new fabrc architecrure. But please do it in the Maintenance window since all the FPC's would go for restart.

2.  Issue "restart chassis-control soft" if GRES enabled and  This generates a SIGHUP signal to the chassisd. Chassisd parses the new configuration. None of the FPC’s is restarted. All Interfaces are up. Traffic is not affected.

Verification of fabric plane with proper SCBE mode:
-------------------------------------------------------------------

lab> show chassis fabric mode
Fabric Operating Mode :
Redundant Fabric    >>>>>>>>>>>>>>>>>>>>>




lab> show chassis fabric summary
Plane State Uptime
0 Online 4 days, 6 hours, 53 minutes, 40 seconds
1 Online 4 days, 6 hours, 53 minutes, 35 seconds
2 Online 4 days, 6 hours, 53 minutes, 31 seconds
3 Online 4 days, 6 hours, 53 minutes, 26 seconds
4 Spare 4 days, 6 hours, 53 minutes, 21 seconds >>>>>>>>>>>>>
5 Spare 4 days, 6 hours, 53 minutes, 16 seconds  >>>>>>>>>>>>>>