Will there source port conflict if the SNAT address same as one of the health monitor src-ip?

Hello,

You won't run into any problems with this setup until you reach 65k concurrently opened server-side connections from that same Source IP address TO the same Destination Host IP. That's A LOT, and very hard to breach. If that happens, you will have TCP source-port exhaustion problem (will be reported in /var/log/ltm).

To address this problem, you can switch out from SNAT Automap and opt to use SNAT Pools instead; alternatively look into other optimizations such as OneConnect for HTTP services.