CCNP Practice Question: Runs the following command on Router R3: R3# show…

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  The NAT pool has exhausted all available addresses.

  Why it's wrong here

  The NAT pool has not exhausted its addresses: only 5 of 10 available public IPs are currently in use, leaving 5 free. Exhaustion would manifest as failed address allocation attempts and typical error messages in debugs (e.g., "NAT: out of addresses"), but here there is no such indication. Additionally, PAT (which is being used) conserves addresses by multiplexing thousands of internal hosts onto a single public IP, making pool exhaustion far less likely in this scenario.

• ✗

  The NAT translations are all static.

  Why it's wrong here

  The translations are not static. Static NAT entries are manually configured, persist regardless of traffic, and appear in `show ip nat translations` without the "extended" keyword — they map a fixed inside-local to a fixed inside-global address. In contrast, the output shows 5 dynamic translations, evidenced by their temporary nature (they time out after the idle timeout) and by the "extended" flag, which only appears on dynamically created PAT entries. A static-only NAT table would contain all-to-all static mappings, not a mix of dynamic extended entries.

• ✓

  The router is performing Port Address Translation (PAT).

  Why this is correct

  The router is indeed performing Port Address Translation (PAT), also known as NAT overload. The key clue is that the translation entries are labeled "extended" — this means they include Layer 4 port numbers (TCP/UDP) in addition to IP addresses, allowing many inside hosts to share a single outside public IP. PAT is the standard mechanism for conserving IPv4 addresses in enterprise and home networks, and it is confirmed by the presence of extended dynamic translations in the output.

• ✗

  The inside interface is GigabitEthernet0/0.

  Why it's wrong here

  The inside interface is not GigabitEthernet0/0. In a typical NAT configuration, the inside interface connects to the internal LAN and carries the private IPv4 addresses that need translation, while the outside interface faces the public network. Although the translation output does not directly print interface names, the routing and NAT setup in this scenario places inside on GigabitEthernet0/1 (used for internal traffic) and outside on GigabitEthernet0/0 (the WAN uplink). Thus, the inside interface is incorrectly identified as Gi0/0.