[sync] Activesync on local network

[Arjen de Korte]

Citeren Ad-Min <admin at 123.dynu.com>:

> After much fumbling around, I finally got activesync to work. It works great
> on the 2 devices I tried it on (Outlook 2016 and Android). However, I can't
> access activesync from the local network. Is there some method that could
> give the same setup access from both inside and outside the network? I'm
> definitely a noob with this stuff. Thanks.

I assume your server where Horde lives, is on the internal network and  
has an IPv4 address in the RFC-1918 (= private) range (192.168.0.0/16,  
172.16.0.0/20 or 10.0.0.0/8) and is reachable from outside through  
port forwarding from an external (= non-private) IPv4 address. In that  
case, all you need to do is to make sure the DNS server your internal  
users use, returns the private address for lookups from internal  
clients. Alternatively, you could setup your router to forward  
requests from internal clients to the external IPv4 address to the  
internal IPv4 address. If this is possible depends on the router  
you're using.

If your LAN and server are IPv6 enabled, there usually is nothing you  
need to do.

If you need more information, Google for 'split brain DNS' or 'split  
horizon DNS'. This is really more networking related, than Horde.