Hello,
I have the same problem under UBUNTU and OnlyOffice in a docker image.
Could you resolve that?
Regards.
As far as I know the OnlyOffice server must be accessible for both the Browser Client and Nextcloud Server (using the URL given).
If you guys have both NC and OO at the same network (or same server), you may want to configure your server host file so it looks for localhost/local IP when your.office.domain is called.
In my VM with the servers I edited the /etc/hosts file to resolve the domain to 127.0.0.1 ( localhost ).
On my machine I have also changed C:/Windows/System32/drivers/etc/hosts to point to the VM’s IP inside my network.
I have then used a valid letsencrypt certificate for the domain. I can create certs using DNS (dynu.com), so I already had a test domain cert created.
I have changed the OnlyOffice default por to 9988 BEFORE INSTALLING (as per instructions), but also changed the SSL port from 443 to 4443 at the onlyoffice-documentserver-ssl.conf.template copy.
And it worked fine (quite fast actually).
So if your local network does not have NAT fallback enabled, your external domain will not get resolved to the correct local IP and it wont be accessible for the Nextcloud server, even though it may accessible for you at the client side.
So clients from outside the network would resolve to external ports and IPs, while clients inside the LAN would need to resolve to the corresponding local ports and IPs.
I have a situation where my router redirects mydomain to an internal IP (eg. 10.0.10.10) so people can still use the server from inside the LAN correctly (just an example). So check what IP your office domain resolves to and also if each point can access it (only one is not enough).
Also, you may be able to use everything at the default ports IF you use separate domains for nextcloud and onlyoffice (you will need to add it as server name for each config file).
Cheers!
Gus