Iphone Jabber getting error "cannot communicate with the server"

[svadmin]

Hello,

I recently reinstalled jabber on my iphone X and every time I try to login, it asks me for username and password and when I enter them I get the error message "cannot communicate with the server"

I checked the password, on my login, uninstalled and reinstalled jabber. 

I have attached the file with the error message/logs

Can someone help?

[Adam Pawlowski]

1003 is

Cannot communicate with the server #1003

Message: ServiceDiscoveryCannotConnectoToCUCMServer

Description

Cannot connect to UCM

The client is not able to connect to the UCM server. 

You can run this through the solutions analyzer or open a TAC case for more TS information, but more or less the client looks like it is connecting over MRA, and for whatever reason is not able to reach the UCM's UDS page to get information through it. It's possible that your home cluster value isn't checked or similar, I don't know from giving it a 10 second look but you get to Expressway, find your UDS data source, and then fail to be able to talk to it due to reachability it looks like.

[svadmin]

Hi Adam,

I did open a TAC ticket, and the issue was with revers DNS.  we didn't have a pointer DNS look for the servers in the clusters, so once those were added expressway C was able to find the nodes.

This is the path that the TAC enginer was looking at

 Configuration -> Unified Communications -> HTTP allow list ->Automatic inbound rules 

he noticed that our servers has two domain names and the revers for one of them was not setup.

Once the domain admin added the revers pointers and A record for the ip addresses everything worked fine.