Typically, the first CSM installed in a 7705 SAR chassis assumes the role as active, regardless of being inserted in Slot A or B. The next CSM installed in the same chassis then assumes the role as the standby CSM. If two CSMs are inserted simultaneously (or almost simultaneously) and are booting at the same time, preference is given to the CSM installed in Slot A.
If only one CSM is installed in a 7705 SAR, it becomes the active CSM regardless of the slot it is installed in.
To visually determine the active and standby designations, the MS/CTL LED on the faceplate is lit green (steady) to indicate the active designation. The MS/CTL LED on the second CSM faceplate is flashing green to indicate the standby designation.
The following output shows that the CSMv2 installed in Slot A on a 7705 SAR-8 Shelf V2 is acting as the active CSM and the CSMv2 installed in Slot B is acting as the standby.
ALU-1# show card
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Card Summary
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Slot Provisioned Type Admin Operational Comments
Equipped Type (if different) State State
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1 iom-sar up up
A csmv2-10g up up/active
B csmv2-10g up down/standby
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