wow tight security policy.
1. on the switch where the the SVI/vlan interface of the other subnet that you don't want to talk to Secure ACS server, create an extended access list.
ip access extended [acl name or number]
deny ip 192.168.3.0 [wildcard mask] host 192.168.2.17
permit ip any any
2. apply the acl you created on step 1 inbound to the SVI/vlan interface of the other subnet. For example it is on SVI/vlan interface 7.
interface vlan 7
ip access-group [acl name or number] in
3. wr mem
4. Just repeat the same steps above for the other subnets that you don't want to communicate with Secure ACS server.
HTH
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