Hi all,

Just have a quick question. To set up NAT will i require a "registered" global IP address? Like i have been trying to setup NAT on my 2503 router--well i do set it up but it wont work in that i cant ping the " global ip adress" from my another router or from another Pc which are both connected to this 2503 router.

what iam doing is on 2503 iam giving the the local ip as 192.168.1.1(the ip of the pc the router is connected to) and global ip as 203.x.x.x. the ip nat transalation/stat commands shows the configurion to be saved.

when i ping the local ip from another pc or router its working(like the way it works when i dont have any NAT at all) but global ip doesnt. it say "dest not reachable". i have configured both ips as inside ips, as in inside local and inside global, isn't that correct? and also when do we use outside local and outside global, under what circumstances?

what am I missing here? can someone help pls?

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try putting in 'ip nat outside' on the WAN interface, and 'ip nat inside' on the LAN interface. It would also help if you could post your config, I don't know what you've configured already...

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thanks for your reply.

ok, after i setup static route b/w 2503 and 2513 and get both the routers and pcs that connected to them ping each other...this is what i put in one of the router which is connected to a pc with ip addres 192.168.1.1

ip nat inside source static 192.168.1.1 200.200.200.1
interface ethernet 0
ip nat inside
exit
interface serial 0
ip nat outside
exit




also tried this


ip nat inside source list 1 pool nat-pool
access-list 1 permit 192.168.1.1 0.0.0.0
ip nat pool nat-pool 200.200.200.1 200.200.200.1 netmask 255.255.255.0
interface ethernet 0
ip nat inside
exit
interface serial 0
ip nat outside
exit


both of the time same result--cant ping global ip.

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Try this...

interface ethernet 0
ip address 192.168.1.1 255.255.255.0
ip nat inside

interface serial 0
200.200.200.1 255.255.255.0
ip nat outside

ip nat inside source list 1 interface serial 0

access-list 1 permit 192.168.1.0 0.0.0.255



If you only have 1 global IP address there is no ned to creat a NAT pool. Just point to the NAT outside interface. Also your access list was set up to only allow 192.168.1.1 out because of how you had your wildcard subnet mask setup. This is why you could not ping the outside from any internal IP address unless you did a extended ping and originated the ping from that address.

Good luck and let us know if this worked.

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Looks like JPaper did all the work so that the rest of us can sit back and relax on this one. I didn't delve into it, but his config looks solid. He knows his stuff.

Only question I saw unanswered was about needing a registered global IP address. Inside your test network you can assign any address you want, so you don't have to worry about using that 200 public address. Typically most people do stick with private ranges though (10,172.16/12,192.168/24); that's what they're there for.

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Yea after I failed my first attempt at the 640-801 exam because of a NAT sim, I spent a lot of time reading and practicing NAT with my routers.

Here is a very useful link from Cisco on NAT

http://www.cisco.com/en/US/products.../> 091cb9.shtml

After your configuration is set you can use

Show ip nat statistics
and/or
Show ip nat translations

These commands will help you see what is going on with you NAT config.

You do not need a registered global IP address if you are doing offline/lab enviroment testing. So if your routers are not connected to the internet in any way then you can use private IP address for both inside and outside NAT interfaces.

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Tried many things---still no luck..same thing cant ping the global ip from my other router and pc

however i noticed one thing new--when iam pinging the local interface, it goes

reply from 200.x.x.x(which is the global ip iam setting)

but when i ping 200.x.x.x itself

result = dest not reachable

even from the pc the router is connected to directly its the same.

jpaper007--is your config instructions step by step?--it cant be cus that would actually setup router interface's ips. although i tried figuring out the steps you were directing me to but didnt get much out of it

any more suggestions pls any one?

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Can you paste your entire running configuration here? I would like to look at exactly what you have running. Also what IOS version are you running?

Thanks

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http://www.cisco.com/en/US/tech/tk6... 80094e77.shtml

__________________
http://www.cisco.com/univercd/

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Above link got fudged up by the examnotes forum software.

Link check in isle 9!!

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