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I'm configuring a small network at work, and I have some problem.

  • We're assigned 4 external IPs. I have them in range to
  • I mapped one of the global IPs to local IP by NAT, by so that I can access the machine from the outside network. In Cisco configuration, it was ip nat inside source static

And I configured other settings, and opened up other ports so I can ssh into the machine. However, the problem is, I cannot access the local machine by the ip

I was wondering if it's possible to access the local machine by the global IP.

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I'm not following. and are both external addresses. Are you trying to map to, or to Also, you put in your cisco line, so that's also confusing. – Satanicpuppy May 17 '11 at 19:28

Ciscos don't allow access to external NAT address from inside. The traditional way to solve this is by using split DNS: when resolving the name of the server in question, external users should receive, and internal users should receive

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DNS is by far the simplest - resolve to the internal IP internally - but there are other options. You can use policy-based routing to get the traffic to actually translate, though it might require a loopback as the actual NAT interface.

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