All SNMP-related CLI commands operate in the context of a virtual router, which means that you must configure users, traps, communities, and so on for each server. You must set the context using the virtual-router command and then configure SNMP.
The show snmp commands show only statistics and configuration information for the server/SNMP agent that corresponds to the current virtual router context.
The exceptions to this convention are the snmp-server contact and the snmp-server location commands. With these commands, single instances of the contact and the location are created regardless of the number of virtual routers.