Datasheet

Lab – Configuring Dynamic and Static NAT
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What is the translation of the Inside local host address?
192.168.1.20 = _________________________________________________________ 209.165.200.225
The Inside global address is assigned by?
____________________________________________________________________________________
The router from the NAT pool.
The Inside local address is assigned by?
____________________________________________________________________________________
The administrator for the workstation.
b. From PC-A, ping the Lo0 interface (192.31.7.1) on ISP. If the ping was unsuccessful, troubleshoot and
correct the issues. On the Gateway router, display the NAT table.
Gateway# show ip nat translations
Pro Inside global Inside local Outside local Outside global
icmp 209.165.200.225:1 192.168.1.20:1 192.31.7.1:1 192.31.7.1:1
--- 209.165.200.225 192.168.1.20 --- ---
A NAT entry was added to the table with ICMP listed as the protocol when PC-A sent an ICMP request
(ping) to 192.31.7.1 on ISP.
What port number was used in this ICMP exchange? ________________ 1, answers will vary.
Note: It may be necessary to disable the PC-A firewall for the ping to be successful.
c. From PC-A, telnet to the ISP Lo0 interface and display the NAT table.
Pro Inside global Inside local Outside local Outside global
icmp 209.165.200.225:1 192.168.1.20:1 192.31.7.1:1 192.31.7.1:1
tcp 209.165.200.225:1034 192.168.1.20:1034 192.31.7.1:23 192.31.7.1:23
--- 209.165.200.225 192.168.1.20 --- ---
Note: The NAT for the ICMP request may have timed out and been removed from the NAT table.
What was the protocol used in this translation? ____________ tcp
What are the port numbers used?
Inside global / local: ________________ 1034, answers will vary.
Outside global / local: ________________ 23
d. Because static NAT was configured for PC-A, verify that pinging from ISP to PC-A at the static NAT public
address (209.165.200.225) is successful.
e. On the Gateway router, display the NAT table to verify the translation.
Gateway# show ip nat translations
Pro Inside global Inside local Outside local Outside global
icmp 209.165.200.225:12 192.168.1.20:12 209.165.201.17:12 209.165.201.17:12
--- 209.165.200.225 192.168.1.20 --- ---
Notice that the Outside local and Outside global addresses are the same. This address is the ISP remote
network source address. For the ping from the ISP to succeed, the Inside global static NAT address
209.165.200.225 was translated to the Inside local address of PC-A (192.168.1.20).
f. Verify NAT statistics by using the show ip nat statistics command on the Gateway router.
Gateway# show ip nat statistics
Total active translations: 2 (1 static, 1 dynamic; 1 extended)