How can we help you today?
Start a new topic

VPN on snom D725

Prehistory: I have over 15 of SNOM 720 and 760 phones on my IT sector, but not so long ago one of them needed to be replaced and I purchased new D725 which I was told is going to be replacement model for 720.

So, I've updated device to the latest firmware and patched it with VPN addition patch for the VPN support is crucial for our IP telephony to work as they connecting via it to the network where 3CX PBX resides.

Main issue is: when I telling phone to load VPN .tar archive it's loading archive and rebooting to activate. And after that it's acting up. Label "SNOM725-SIP-8.7.XXX" changing with "Starting phone application" still persist even when phone boot complete. Phone restarting at it's own will and could not handle calls, bootloops are also happen often. here is the VPN config that worked perfectly on 720 and 760:

dev tun
cipher BF-CBC
auth SHA1
resolv-retry infinite
remote 95.XXX.XXX.XXX 1194 udp
ca /openvpn/ca.crt
cert /openvpn/phone1.crt
key /openvpn/phone1.key
ns-cert-type server
comp-lzo adaptive

Best Answer

You're welcome.

Are you able to configure and setup a network Syslog Server and possibly a Netcat Server in order to capture the logs from the phone so we can determine what is happening?

Network Syslog Setup

1. Login to webinterface

2. Select Log

3. Configure the log level to 9

4. Download and install a Syslog Server to a local PC (

5. Select Advanced > Network > at the bottom of the screen enter the ip address of the PC hosting the Syslog Server

6. Replicate the problem

7. Attach the file to the ticket

ok, here they are

NetCat log:
Syslog file :


Is this Syslog from a Snom D715? Is there anything connected to the USB port?

no, nothing attached to USB
And it is SNOM D725


So, any ideas what might be causing instability ?


It seems like you may be experiencing a known "restating application" issue that occurs when/if vpn_netcatserver is misconfigured or configured and the netcat server is not responding.


The work-around is to remove any reference to a netcat server in this seting if it is not being used to debug a VPN connection. If you do have to use it to debug the VPN, it is suggested to remove the netcat server because credentials for the OpenVPN connection are captured in the netcat log.


Another thing you will want to do is make sure the timing on the OpenVPN Server and the phone are in sync by using NTP at both locations.

Please give this a try and let us know if the application restarting is still occurring.

Ok, will do.


So, it seems like netcat was causing that thing to happen
Very weird bug, but thank you a lot.
Will monitor phone behavior  for some time though. Just in case


Glad to hear it's working for you now.

Ok, so far no other issues were reported and now I may conclude that it WAS netcat server.
So thanks again.



You're welcome.

Login or Signup to post a comment