Help with NAT rule

smcanuffsmcanuff Member Posts: 27 ■□□□□□□□□□
in CCNP
I have a 1841 rounter, connect to two diff.. ISP, I set up sla, so if ISP "A" fail it fail to ISP "B". The problem I have is when ISP "A" is up I want to use my public IP that I got from ISP "B" in my NAT rule to get access inside my network, eg RDP, SMTP. The NAT rule only works when I fail over to ISP "B"
Can someone point out to me what I am missing.
Don't worry about what's ahead. Just go as far as you can. From there, you can see farther:cheers:
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  • M4verickM4verick Member Posts: 86 ■■□□□□□□□□
    Someone please correct me if I'm wrong as I haven't set this up myself before. But I would think you'd probably have to work with both ISPs regarding this issue.

    I think you'd talk to ISP A to route for that IP address through BGP so that the rest of the internet knows that your IP address could be reached through ISP A as well as ISP B. I would also imagine there would probably be an additional fee required for that.
    Isn't it funny how after you have the certifications, you don't care about sharing them as much?
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  • networker050184networker050184 Mod Posts: 11,962 Mod
    M4verick is correct. The kind of redundancy you want usually needs a BGP set up and your own IP space.
    An expert is a man who has made all the mistakes which can be made.
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  • ColbyGColbyG Member Posts: 1,264
    networker050184 wrote: »
    M4verick is correct. The kind of redundancy you want usually needs a BGP set up and your own IP space.

    I'm not sure what the OP is saying exactly. If he wants to ALWAYS use the IP from ISP B, this is possible. But if he wants to failover automatically, yea, he'll need BGP.

    If he always wants to use ISP B's IP, he can do that by load balancing instead of running failover. Something like this:

    IOS NAT Load-Balancing with Optimized Edge Routing for Two Internet Connections - Cisco Systems

    Then he uses the Static NAT statement with ISP B's IP. But he obviously loses connectivity if ISP B is down.
    http://blog.alwaysthenetwork.com
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  • networker050184networker050184 Mod Posts: 11,962 Mod
    ColbyNA wrote: »
    I'm not sure what the OP is saying exactly. If he wants to ALWAYS use the IP from ISP B, this is possible. But if he wants to failover automatically, yea, he'll need BGP.

    If he always wants to use ISP B's IP, he can do that by load balancing instead of running failover. Something like this:

    IOS NAT Load-Balancing with Optimized Edge Routing for Two Internet Connections - Cisco Systems

    Then he uses the Static NAT statement with ISP B's IP. But he obviously loses connectivity if ISP B is down.

    Yeah, but if his link to ISP B goes down there will be no way to reach that IP through ISP A without getting ISP A to advertise ISP Bs IP space.
    An expert is a man who has made all the mistakes which can be made.
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  • ColbyGColbyG Member Posts: 1,264
    networker050184 wrote: »
    Yeah, but if his link to ISP B goes down there will be no way to reach that IP through ISP A without getting ISP A to advertise ISP Bs IP space.

    That's what I said in the last line.icon_cool.gif
    http://blog.alwaysthenetwork.com
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  • networker050184networker050184 Mod Posts: 11,962 Mod
    ColbyNA wrote: »
    That's what I said in the last line.icon_cool.gif


    I just skimmed. Your idea was so horrible I couldn't concentrate. icon_wink.gif
    An expert is a man who has made all the mistakes which can be made.
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  • ColbyGColbyG Member Posts: 1,264
    hahahahahahahaha
    http://blog.alwaysthenetwork.com
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  • M4verickM4verick Member Posts: 86 ■■□□□□□□□□
    networker050184 wrote: »
    I just skimmed. Your idea was so horrible I couldn't concentrate. icon_wink.gif

    hahahahaha

    Thanks for confirming my theories though guys!
    Isn't it funny how after you have the certifications, you don't care about sharing them as much?
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  • APAAPA Member Posts: 959
    networker050184 wrote: »
    I just skimmed. Your idea was so horrible I couldn't concentrate. icon_wink.gif

    BAHAHA! Classic :)
    CCNA | CCNA:Security | CCNP | CCIP
    JNCIA:JUNOS | JNCIA:EX | JNCIS:ENT | JNCIS:SEC
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