# Chat mail relay Federation **URL:** \ **Category:** Chatmail Relays\ **Created:** [June 12, 2025, 8:43pm UTC](https://support.delta.chat/t/chat-mail-relay-federation/3837 "2025-06-12T20:43:01Z")\ **Posts on this page:** 1\ **Showing post:** 10
**Author:** ![WofWca](https://support.delta.chat/user_avatar/support.delta.chat/wofwca/32/1702_2.png) [@WofWca](https://support.delta.chat/u/WofWca)\ **Post date:** [June 15, 2025, 7:41pm UTC](https://support.delta.chat/t/chat-mail-relay-federation/3837/10 "2025-06-15T19:41:13Z")
For other readers, here is a follow-up discussion: > [@Cannot run Chatmail relay](https://support.delta.chat/t/cannot-run-chatmail-relay/3831/6): > > To be honest, the chat mail relay Federation works every other time, but somewhere it doesn’t work at all. No one can answer me, as if they are hiding something. The federation only works for the domain [testrun.org](http://testrun.org) otherwise, everything is closed. I was wrong to say recently that everything was working, but not everything is working. Well, if that’s what the creators of the repeater want, let them. It’s strange that the guys who raise their servers don’t understand why the federation is working … Also there is a related issue: > > > for someone setting up a server for the first time like me, just following the g…uide/readme was not enough, ex. the guide assumes you already have a VPS with DNS configured to point to your domain, it would be good to mention that the A record is needed to be added with the domain and corresponding VPS IP, without this it is not possible to start the guide, I had to add this initial records before being able to properly run the \`cmddeploy run\` command: > > !\[Image\](https://github.com/user-attachments/assets/50c45daf-bf6d-486a-95d9-3b9f505ebbd2) > > more important to point out: after finishing the deployment, my server was still not able to communicate with Gmail because \[Reverse DNS lookup\](https://en.wikipedia.org/wiki/Reverse\_DNS\_lookup) records were not configured, the guide doesn't mention this, which is important for federation with the "big providers", the google error: > > \`\`\` > The IP address sending this message does not have a PTR record setup, or the corresponding forward DNS entry > does not match the sending IP. As a policy, Gmail does not accept messages from IPs with missing PTR records. > For more information, go to https://support.google.com/a?p=sender-guidelines-ip > \`\`\` > > after setting up the PTR records in my VPS provider and waiting for some minutes for it to propagate to google DNS servers, then sending messages worked, the PTR can be checked with \`nslookup\` or https://www.whatsmydns.net/dns-lookup/ptr-records --- _[View the full topic](https://support.delta.chat/t/chat-mail-relay-federation/3837)._