Minor Mismatch for Stack Units

With a minor mismatch, an operating stack can still exist, but traffic is dropped from all ports except the stacking ports for units with the mismatched software. You can download the correct image to the mismatched devices from the active controller. A minor software mismatch means that there is no IPC or election algorithm change, but there is a release version disparity. Minor software mismatches can occur with patch release upgrades. The system logs and displays a message similar to the following.

Warning! put stack unit 2 to non-operational reason=image mismatch

The show stack command displays output similar to the following.

ICX7850-32Q Router# show stack
T=31m6.8: alone: standalone, D: dynamic cfg, S: static
ID   Type          Role    Mac Address    Pri State   Comment                   
1  S ICX7850-32Q   active  d4c1.9e18.3731   0 local   Ready
2  S ICX7850-48FS  standby d4c1.9e18.8dd9   0 remote  NON-OP: image mismatch
    active       standby                                                       
     +---+        +---+                                                        
 =3/5| 1 |3/1==2/1| 2 |2/5=                                                    
 |   +---+        +---+   |                                                    
 |                        |                                                    
 |------------------------|

Normally, the system recovers from a minor image mismatch using the Auto Image Copy feature. However, if the feature has been disabled or if the configuration of a stack unit does not match the configuration of the active controller, the stack unit does not function. In this example, unit 2 is non-operational due to an image mismatch. To correct this situation, use the copy flash flash command. Refer to Copying the flash image to a stack unit from the active controller.