OpenVPN with QNAP and Yeastar

Hello,

I am using Milrotik CCR1036-8G-2S+ where openvpn server is configured.
Several Milrotik routers are connected to the CCR using openvp without issues.
I am trying to get Qnap TS421 with version 4.3.3 to connect to the CCR using openvpn with not luck
I also have to have the Yeastar TG100 GSM gateway connect as openvpn client to the CCR but with vain.

On the CCR I am not seeing any activities.
Could anyone share his experience for QNAP and Yeastar openvpn client settings ?

For years the Mikrotik implementation of OpenVPN has not been supporting UDP and compression (there is a related topic on this site). So if your boxes can be configured accordingly (TCP transport, no compression), you should be able to set up the connection. Otherwise there is no way.

I was aware of the protocol but not the compression part. Thank you for pointing that out.
I managed to make the Qnap work however I had to disable the check client certificate on the Mikrotik side.
As for the yeastar I still did not check that out.