OpenVPN annoying "duplicate packet, dropping" log message (looks like bug in ovpn logging)

RouterOS General
1

After migration from RB750G v6.27 to CRS-125 v6.32.3 there was starting annoying log messages from OpenVPN server if any client is connected.
Frequency of this messages is diferent, sometime 1-2 per day, sometime 15 per minute. This message is going to memory, remote syslog and console too.
Especially when working through ssh is very annoying.

The message on console and remote syslog:

jul/14/2016 09:23:25 ovpn,debug,error,,,,,,,,,l2tp,info,,debug,,,critical,,,,,,,,,,,,,warning duplicate packet, dropping

The same message in memory:

09:23:25 ovpn,debug,error,10820,11808,33692,32664,25472,30620,32480,33688,l2tp,info,33692,debug,79,65535,critical,10176,47396,25488,29944,30696,26392,11808,30084,30080,30620,37808,30620,warning duplicate packet, dropping

Regarding “wide topics” of message, it looks like bug in OpenVPN implementation in RouterOS (and is not possible to workaround it by “!$topic”).
Upgrade to 6.32.4 and 6.34.6 does not helped.
In original OpenVPN is possibility to mute it by “–mute-replay-warnings” option, but here is unfortunately not.

2

Hi, I’ve got the same message in my log.
ovpn works fine but i want to resolve this issue, whats it about and what can i check??

20:58:16 echo: ovpn,debug,error,l2tp,info,debug,critical,wa
rning duplicate packet, dropping

thanks for the help in advance…

3

I have ROS 6.42.1 and I’m struggling with the same issue here. I cannot stop this and basically the only issue here for me is this output on logs and the unuseful memory usage, because the VPN is working perfectly for me.

4

I found a way to get rid of those annoying messages and in the same time keep important ovpn info topic in logs:

/system logging
set 0 topics=info,!ovpn
set 1 topics=error,!ovpn
set 2 topics=warning,!ovpn
set 3 topics=critical,!ovpn
add action=echo topics=ovpn,info,!debug

Hope will help someone until Mikrotik will fix the bug.

5

seems like this the only fix for now…
everything works, but this annoying red warning…

6

unfortunatelly this problem still exists in the year 2020…Where is the support ??