WebDocuments
Figure. WebDocuments Service tab.
WebClient Host
When using two load balanced servers, the SMTP Server field should be set like this:
127.0.0.1;localhost2
where localhost2 is to be mapped on each of two front end servers – for server 1, localhost2 is NAT IP of server 2 and vice versa.
In the load balanced scenario you might have to use the hosts file (\windows\system32\drivers\etc\) to have different settings for each front server, so each one uses the other one as redundancy.
Example
Then you map in that server's hosts file localhost to server 2's IP.
In server 2, SMTP/POP/IMAP fields = 127.0.0.1;localhost2
and same thing, in server 2's hosts file you put server 1's IP.
If you use a different port then the default one (for SMTP) in this scenario, you have to define this port (only) after the second host.
Example: 127.0.0.1;localhost2:587