MARS has to be configured to talk to the IPS SSMs in each of the 2 ASAs independantly. MARS needs to treat them as 2 separate sensors.
The ASAs are capable of active/active configurations when using multiple contexts.
For context A the ASA on the left can be active and the ASA on the right in standby.
For context B, however, the ASA on the left can be in standby, and the ASA on the right be active.
So traffic can be actively flowing through each ASA.
So the SSM in the left ASA would be monitoring traffic in context A.
And the SSM in the right ASA would be monitoring traffic in context B.
(NOTE: During an ASA failure, both contexts would be made active in the other running ASA, and both contexts monitored by the SSM in the running ASA.)
Because both SSMs are actively monitoring, each SSM needs its own ip address and MARS needs to connect to and monitor both SSMs.
Unlike the ASA where the ASA has an ip address unique to each context (and passed between ASAs during a failover). The SSMs do NOT have ip addresses unique to the contexts. The SSM has just it's single IP address regardless of the number of contexts or failover configuration of the ASA.
In the future the plan is to have the 2 SSMs be able to sync their sensing configuration settings, but even then they will still each need their own unique ip address and name, because in an active/active ASA configuration both of the SSMs will be actively monitoring different traffic.
So MARS will always need to connect to each SSM's ip address uniquely.
