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I have a working OWA internally and externally. Users can access OWA externally through and internally through the IP address. What I want is internal users to access OWA by browsing to rather than the IP address for obvious easy of use.

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up vote 8 down vote accepted

This is a DNS problem, not a OWA one.

If your firewall/proxy can't handle requests for from the inside, then you will need to create a "shadow" zone for in your internal DNS servers, which maps your public names to internal IP addresses.

This way, will map to some public IP address when resolver from the outside, while it will map to your CAS server's internal IP address when resolved from the inside.

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Whats a "shadow" zone and how do I create one? Does that mean it can resolve names to the internal address, internally? So externally nothing will change. I don't really want internally traffic resolving to an external address when I know it works internally when browsing to the internal IP! – stead1984 Nov 24 '09 at 13:35
It's exactly that. If you create a zone called "" in your internal DNS server, it will answer requests for names in that zone with whatever IP addresses you tell it to use; so, a client asking for to the internal DNS server can get a completely different answer than a client asking the "real" external DNS server. – Massimo Nov 24 '09 at 14:34

If you are not using AD DNS for your External DNS needs, then you can add "" to your AD DNS, using your internal IP address.

This will solve your problem by providing the internal IP address to people in the office, but people outside will still resolve your external IP address as they do now.

However, once you add to your AD DNS, AD will try and resolve ALL YOUR INTERNAL DNS REQUESTS - so you'll have to duplicate, or have appropriate counterparts for all of your external DNS records in AD.

Also be aware that people with laptops may cache the DNS records for either the internal or external IP address, and it could break owa for them when they move in and out of the office. - the solution is for them to flush their DNS or reboot.

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It should work fine on the external address. Is your AD Domain name the same as your web domain name? If it is, this could cause DNS problems internally that would prevent this.

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No our domain is .local – stead1984 Nov 24 '09 at 13:28
@mMarkM Actually no - there are good reasons why it might well not work with the external address, a lot of routers are set up to not allow loop backs from inside the network to the external IP address (I can't comment on why, but presumably its a security thing) so you need to deal with that by using and appropriately configuring a local DNS server as described in other answers – Murph Nov 24 '09 at 15:04

Have you tried to get to in from inside using the external address? If it does not work, then just add a DNS record to your AD DNS server for the FQDN of the external address and point it to the internal IP address.

Or figure out why an external domain (yours) is not resolving correctly since your internal one as .local should not interfere with the the resolving of the external one.

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