OK, I am the first to admit that as an officially “old fart” there are times when I lose the thread. I also admit that there are a few things “Grandstream” that confuse the hell out of me. So, with all of that stated …
I have a weird issue with OpenVPN that has me totally scratching my head, here is the scenario: I have a Pi serving up OpenVPN (one of Jim Connell’s units) and it works fine. If I take a 2135 or a 1780 with clean factory reset and apply all of the OpenVPN settings everything works as expected. The phone connects over OpenVPN and I can set up extension and all that. No issue at all.
However, if I provision the phone on the UCM network using Zero Config and then add in OpenVPN the phone will see OpenVPN on the UCM LAN. Once you put the phone on the remote network OpenVPN fails. I cannnot see anything in the templates used for provisioning that might cause the issue but then I’m not an expert. A weirder wrinkle is that DP752 will work perfectly even if provisioned via ZC and then taken to remote site.
I am going to try a test of using ZC to provision a 2135 and NOT adding in OpenVPN at that point. Take phone to remote site and then add in OpenVPN to see if it will work.
If anyone has a thought I’m all ears. OpenVPN works fine, it’s something in the steps of building/provisioning the phone that breaks things.