How does Exchange Server know that a user's request is from intranet? A user from intranet can acce

Rakanoth

Junior Member
Oct 6, 2017
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How does Exchange Server know that a user's request is from intranet? A user from intranet can access his/her own emails just by typing exchange server's URL which is https://remote.companydomain.com/owa

But no one outside intranet can access his/her own emails by using this address. They have to somehow connect to intranet, which is not possible. It is disabled because of security concerns etc.

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My question is how a user is able to send request to Exchange server by typing https://remote.companydomain.com/owa and? I should make this question a little more clear:
1.) A user outside intranet types https://remote.companydomain.com/owa and CANNOT access his or her email.
2.) A user inside intranet types https://remote.companydomain.com/owa and CAN access his or her email.

These URLs are exactly the same. I feel like that for the intranet connection there should be a different URL. I also feel like that using remote.companydomain.com/owa should route the request through Internet and then back to Exchange Server. But this does not happen! It directly goes trough intranet to the Exchange Server! How?
 

mxnerd

Diamond Member
Jul 6, 2007
6,799
1,101
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You have to port forward ports 80 & 443 to your exchange server on your router/firewall.

Usually for intranet setup, companies use companydomain.local for internal use and companydomain.com for external use.

for intranet use https://remote.companydomain.local/owa

for internet use https://remote.companydomain.com/owa

You have private IP addresses like 192.168.x.x/172.16.x.x/10.x.x.x for intranet and public IP addresses for internet.

When access intranet from internet, you use port forwarding.

==

If you want to use same URL for intranet and internet users, (you already setup your domain as companydomain.com internally on your domain controller) you have to use Split DNS configuration.

Where internet users use external DNS (usually hosted at ISP), but intranet users use internal DNS

https://www.google.com/search?q=split+dns

https://www.youtube.com/results?search_query=split+dns

https://www.youtube.com/watch?v=d_XCpr1v_w

==

You also should not let intranet users get public IP for the URL, which goes out to the internet then routes back to Exchange server, which slows down a lot and does not make sense.
 
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