Question

Good afternoon. There is RUTH14 and 14 Mikrotik RB951UT-2nd connected via L2TP without using encryption.

Very often the connection breaks and is not restored for a long time. In the logs I get this message "check control: Received out of order control packet on tunnel 134 (got 10, expected 11)

handle control: bad control packet!

Ovverriding mtu 1500 to 1400

Overriding mru 1500 to mtu value 1400"

firewall turned off

Sometimes the connection is quickly restored. Sometimes only after a few hours. Help deal with the problem. What to pay attention to first of all?

maybe it's in mtu and mru?

Answer 1

Hello,

Based on the screenshot you are using older firmware. For one, you could try updating to the latest and see if the issue persists.

If that des not resolve the issue, I would like to review your configuration and device logs. Thus, attach a troubleshoot file to your question. First, make sure to replicate the issue, then access router's WebUI, go to System -> Administration -> Troubleshoot section and download troubleshoot file from there. The logs in the file might provide more insight into the issue.

Attached files are private and visible only to Teltonika Moderators.

Best regards,

Comments

what file from the archive should be attached? the archive is very large

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I will send you an email, where to forward the archive. However, please update firmware first, just to make sure that the issue has not been solved in subsequent releases and only generate the file, if the errors persist.

Best regards,

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I installed the latest firmware from the official site. RUTX_R_00.07.03.4

and emailed you the log files. I hope this will be enough to sort it out.

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One of the downloaded files has 7.0 firmware, while the other is somewhat broken, incomplete and larger than it is supposed to be. Not much can be gained from it. 

I assume, you have performed update with Keep settings.

If that is the case, could you generate a backup of your configuration, reset the device, reconfigure and download a new file, if the issue persists?

Best regards,

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sent you a whole log file. See how it will be possible. The problem remains relevant.

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The sent file is taken from RUTX_R_00.07.00 firmware.

First, I need to be sure that the issue is present on the latest firmware. Next, if I am unable to provide a solution, in order to forward the issue further, I still need the file generated on the latest firmware to have it looked at.

Apologies for the inconveniences.

Best regards,

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Good afternoon. I updated the firmware to the latest version and added a new log file. Look please. Judging by the messages in the logs, nothing has changed.

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I have done some testing with Mikrotik hAP ac³, but L2TP connection remained stable.

Have you noticed, if there are any circumstances, such as increase in traffic, when the disconnects begin to occur? 

Would it be possible for you to share the configuration settings of Mikrotik in a private message?

I would also like you to login to the RUTX14 router via SSH and enable additional logging. To achieve this, once logged in, execute the following command:

• vi /etc/ppp/options

Remove # mark from debug option. Once done, press Esc, then enter :wq and press Enter.

Restart L2TP service with the command:

•  /etc/init.d/xl2tpd restart

Wait some time, generate a new troubleshoot file and attach it as well.

Best regards,