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Problem with this NAT configuration?

CrunchyhippoCrunchyhippo Member Posts: 389
Ok, it's befuddling me. It's a simple NAT translation, but the lab never told me if I should be able to ping out to the loopback address; I think I should be able to. See if you can spot any issues I may have missed.

ISP Router
loopback 172.16.1.1 /32
serial 0 - 200.2.2.17 /30
clockrate
Static route: 199.99.9.32 255.255.255.224 200.2.2.18

Gateway Router
serial 0: 200.2.2.18 /30
fast eth: 10.10.10.1 /24
default route: 0.0.0.0 0.0.0.0 200.2.2.17

Two hosts connect to a swich, with connects with the Gateway router.

Host 1
IP 10.10.10.10 /24
Default gateway: 10.10.10.1/24

Gateway router
ip nat pool Alpha 199.99.9.40 199.99.9.62 netmask 255.255.255.224
access-list 1 permit 10.10.10.0 0.0.0.255
ip nat inside source list 1 pool Alpha

Specified inside and outside NAT interfaces on Gateway router

From PC 1, I tried to ping 172.16.1.1 (the loopback interface of the ISP) and was unable to ping it. I couldn't ping the serial interface of the ISP router, either. I could ping the serial of the Gateway router, however. The Gateway router could ping the serial interface of the ISP router, so that link was good.

Suggestions?
"Computers in the future may weigh no more than 1.5 tons." - Popular Mechanics, 1949

Comments

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    networker050184networker050184 Mod Posts: 11,962 Mod
    Can you post the running config?
    An expert is a man who has made all the mistakes which can be made.
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    r_durantr_durant Member Posts: 486 ■■■□□□□□□□
    Which specific interfaces on the Gateway router did you specify as in and out?

    Before you had applied the NAT were you able to ping the loopback or ISP s0 from PC1? If you haven't, verify that the routing works first before applying the NAT...otherwise you may be beating a dead horse...

    How are you advertising the loopback interface to the Gateway router?
    CCNA (Expired...), MCSE, CWNA, BSc Computer Science
    Working on renewing CCNA!
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    NetstudentNetstudent Member Posts: 1,693 ■■■□□□□□□□
    What about show ip nat translations and show ip nat statistics? ANything there?
    There is no place like 127.0.0.1 BUT 209.62.5.3 is my 127.0.0.1 away from 127.0.0.1!
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