Datasheet

Lab – Configuring Port Address Translation (PAT)
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Hits: 24 Misses: 0
CEF Translated packets: 24, CEF Punted packets: 0
Expired translations: 0
Dynamic mappings:
-- Inside Source
[Id: 1] access-list 1 pool public_access refcount 3
pool public_access: netmask 255.255.255.248
start 209.165.200.225 end 209.165.200.230
type generic, total addresses 6, allocated 1 (16%), misses 0
Total doors: 0
Appl doors: 0
Normal doors: 0
Queued Packets: 0
c. Display NATs on the Gateway router.
Gateway# show ip nat translations
Pro Inside global Inside local Outside local Outside global
icmp 209.165.200.225:0 192.168.1.20:1 192.31.7.1:1 192.31.7.1:0
icmp 209.165.200.225:1 192.168.1.21:1 192.31.7.1:1 192.31.7.1:1
icmp 209.165.200.225:2 192.168.1.22:1 192.31.7.1:1 192.31.7.1:2
Note: Depending on how much time has elapsed since you performed the pings from each PC, you may
not see all three translations. ICMP translations have a short timeout value.
How many Inside local IP addresses are listed in the sample output above? __________ 3
How many Inside global IP addresses are listed? __________ 1
How many port numbers are used paired with the Inside global addresses? _________ 3
What would be the result of pinging the Inside local address of PC-A from the ISP router? Why?
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The ping would fail because the router knows the location of the Inside global address in its routing table
but the Inside local address is not advertised.
Part 3: Configure and Verify PAT
In Part 3, you will configure PAT by using an interface instead of a pool of addresses to define the outside
address. Not all of the commands in Part 2 will be reused in Part 3.
Step 1: Clear NATs and statistics on the Gateway router.
Step 2: Verify the configuration for NAT.
a. Verify that statistics have been cleared.
b. Verify that the outside and inside interfaces are configured for NATs.
c. Verify that the ACL is still configured for NATs.
What command did you use to confirm the results from steps a to c?
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