[Synapse] Cannot connect to other server

[lnoferin]

My YunoHost server

Hardware: Raspberry Pi at home
YunoHost version: 11.0.10.2
I have access to my server : Through SSH | through the webadmin
Are you in a special context or did you perform some particular tweaking on your YunoHost instance ? : no

Description of my issue

I reinstalled synapse on my server and I can connect to it either with element-web either with desktop/android client.

But if I try to join to some rooms on other server I get always an error.

I tried to look at log but it is really huge with many lines always: what should I have to look for the error in log?

[nr458h]

Did you have a look at the diagnosis? This sounds like a missing open port.

GitHub - YunoHost-Apps/synapse_ynh: Matrix server (synapse) package for YunoHost

[lnoferin]

This sounds like a missing open port.

I cannot see any problem, the only port I have open for synapse is 8448, right?

[nr458h]

@lnoferin

But if I try to join to some rooms on other server I get always an error.

What kind of error?

And please have a look at the docu - I edited my post. There are problems from time to time if your Servername @domain.tld and the domain of synapse is different sub.domain.tld

[Mamie]

For what I remember, you need some special DNS configuration to be able to communicate with other servers.
You can check this here : GitHub - YunoHost-Apps/synapse_ynh: Matrix server (synapse) package for YunoHost

[lnoferin]

@nr458h

What kind of error?

A simple and generic message like

Entry failed
An error occured in the entry

(I don’t know the english version because I have it in my native language)

Se I would like to look for the error in the log.

@nr458h

And please have a look at the docu - I edited my post. There are problems from time to time if your Servername @domain.tld and the domain of synapse is different sub.domain.tld

Where is your post?

[lnoferin]

@Mamie

For what I remember, you need some special DNS configuration to be able to communicate with other servers.
You can check this here : GitHub - YunoHost-Apps/synapse_ynh: Matrix server (synapse) package for YunoHost

I followed this document but I think the problem is in the DNS configuration because my DNS provider (gandi) does not permit to change the relevant line in the correct way.

Now I have this line

_matrix._tcp 3600 IN SRV 10 0 8448 matrix.domain.org.

If I try to change it in

_matrix._tcp.domain.org. 3600 IN SRV 10 0 8448 matrix.domain.org.

The change is not recorded

[Mamie]

I have no knowledge about Gandi but here is a federation tester for Matrix : https://federationtester.matrix.org/
Mabe it will give you details.

[lnoferin]

Thanks for the link I did not know before.
It gives me everything correct for my server / domain so I cannot understand what is happening.