Question : Internal Users connecting to server via its external IP instead of internal.

This appears to be an extension to my previous question...
 http://www.experts-exchange.com/Networking/Netware/Q_21919694.html

Some users started complaining of unusually slow performance accessing network files. Users with 100baseT connections seeing 10base2 speeds. Nothing wrong with hardware, no antivirus/spyware stuff, etc, just much slower network performance than expected.

I did find that the users seeing slow performance were somehow being connected to the server via its external IP address rather than the internal one. This isn't too surprising as the router is probably the bottleneck, but my question is, why are SOME users being connected to this address?

By fiddling around and uninstalling and reinstalling the Netware client, I was able to get one of the users connected via the internal IP instead, and performance improved dramatically. But I need a way to make sure things stay on the internal network in future.

I may have noticed a correlation between uninstalling the iPrint client and getting the internal address, but that might just have been a coincidence.

Why would some users get the external address, while others get the internal one? And how can I stop this from happening?

Answer : Internal Users connecting to server via its external IP instead of internal.

Are you using middle tier?

How are the clients configured for login - do you have the server name in the "preferred server" setting?  Is the server name the same as the hostname portion of the public URL?

Maybe, try a) pushing a HOSTS file to everyone, with the internal IP and server name in it or b) remove DNS as a naming component in the Protocol Preferences tab.

The DHCP options for eDirectory server/NetWare server/NDS server (pretty much all the same thing) and SLP DA are on the "Other DHCP Options" tab, on the subnet dealie-bob in the DNS/DHCP console.

Options of interest:

Option#          Name                    Why

78                  Directory Agent      It's the SLP DA.  I put the IP address of the DA server there.
79                  Service Scope        It's the SLP Scope.  I don't use it.
85                  NDS Servers          You guessed it - the aforementioned "eDirectory/etc. server."  It's a multivalue option, put the IP of all your NW servers there.
86                  NDS Tree Name     Nice to have.  
87                  NDS Context          Don't know what good that's for in a small, single-site organization.