NAT Selection with an ACL: PAT a Single Host Only

Bundle lab · $29.99

Configure PAT on an edge router so only PC-A is translated using a standard ACL as the traffic selector. PC-B remains untranslated and fails to reach the ISP, illustrating that NAT occurs only for traffic explicitly matched by the ACL. Validate using host pings and IOS show commands, and interpret ACL hit counters and NAT tables.

Learning objectives

• Mark the correct inside/outside NAT interfaces on an IOS router
• Write a standard ACL that selects a single inside host for translation
• Configure PAT with a single-address pool and tie it to the ACL
• Verify translations and ACL hit counts; explain why unmatched traffic is not translated
• Diagnose failures due to ACL logic or mis-marked inside/outside roles

Troubleshooting focus

• If both hosts succeed, the ACL may be too permissive or not referenced by NAT
• If both fail, inside/outside roles may be reversed or the NAT pool is missing
• If translations appear but replies never arrive, verify the translated address is on the outside segment and that the ISP can reach it