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Cisco 1760 - IP Nat question - GRE

Hi All,

I have been playing with this for a bit now, and dont want to go for my standard hit and miss routine any more!

For the purposes of this exercise, I have 1 global IP - I want that to connect to 3 servers

This should be simple;

ip nat source static tcp insideip1 80 outisdeip 80
ip nat source static tcp insideip2 25 outsideip 25

(i may have left something out of that, but you get the idea - this is all working fine)

Now, the problem is, I want one of those to go to a PPTP server - how do I get GRE to map the same way?

I know I can; ip nat source static tcp insideip3 1723 outsideip 1723 - but that isnt working, and I am assuming the problem is GRE

Ideas, suggestions???

thanks in advance

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1 Solution
It's a big problem. For GRE you must use a 1-1 static nat. You cannot PAT becuase there is no concept of ports with GRE - it's all or nothing. PAT only works for TCP | UDP
There is no workaround. You need a 2nd global for the GRE to work
redseatechnologiesAuthor Commented:
Thanks for coming lrmoore - I appreciate your time.

I was hoping you weren't going to say that, but thought that may be the case.

I dont think this will work either, but humour me :)

Could I;

ip nat source static insideip1 outisdeip
ip nat source static tcp insideip2 80 outsideip 80


static 1-1 from the global to the rras server - then another on top of that.......

that isnt going to work either, is it

'Friad not, my friend...
It's either / or
Either 1-1 nat
or Per port NAT
redseatechnologiesAuthor Commented:

oh well, no second vpn :)

Thanks again for your help lrmoore!

Thanks! I wish I had better news for you...


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