Question

I have a RUTX12 connected to a D-Link DGS-108 gigabit switch (which has been working flawlessly for over a year).  At first I had DHCP disabled and was only using static IP addresses on the network, and that seemed to be stable for a few days.  I have since enabled DHCP on the RUTX12, and today I started having issues where the RUTX12 would become unreachable.  Upon checking the D-Link switch, I noted that neither the 10/100 Mbps or 1000 Mbps lights were on.  If I unplug the RUTX12's ethernet cable from the D-Link switch, and plug it into a new port, it suddenly starts working again, and the 1000 Mbps light comes on.

There are several other devices (both 100 Mbps and 1000 Mbps) connected to the switch that keep their connection without a problem and have been plugged in for months at a time, so it doesn't seem to be the switch.

What could be causing this loss of ethernet connection after enabling DHCP (which works)?  Maybe the DHCP enabling is just co-incidental, but either way, the RUTX12 (and only the RUTX12) is losing the ethernet connection to the switch.

Edit: It seems that even with DHCP disabled, this happens every few days.  It's just much more frequent with DHCP enabled.  So this is not specific to DHCP.

Comments

I have now disabled DHCP on the RUTX12 and everything is working fine.

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Hello,

I have setup the same for me and its working fine until now. 

To know what is causing the issue.

Can you please register the device on RMS , in case its not registered can you register ?  And download a troubleshoot file from RMS when the issue is recreated on your side. Don't power off the device or unplug any cable. Just go to RMS and download the troubleshoot file. 

For the troubleshoot download please check here:

How to configure device on RMS

Further with this testing we can know what is happening with the DHCP and LAN , what goes down once issue occurs.

Thanks.

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When the Teltonika device is down, I don't have any internet connection, so I'm not sure how I'm supposed to download the RMS troubleshoot file without first fixing the internet connection (by unplugging the cable).  Surely there would be some local logs that should have more information than the remote management system?

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John,

Would it be possible for you to monitor the RXGoodPkt/TXGoodPkt/RXBadPkt/TXBadPkt counters on the D-Link switch for the port the RUTX12 is connected to ? Does RXBadPkt stays at 0 or does it increase ?

Does the issue occurs if you force the port to 100M/Full ? This worked for me some time ago.

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I'm not sure how I would monitor the RXGoodPkt/TXGoodPkt/RXBadPkt/TXBadPkt counters on the D-Link switch, as it's an unmanaged switch. If there's a method that I'm not aware of, I'd be happy to learn how.

I plan on moving over to a managed Ubiquiti switch as soon as they are in stock, but I'm not sure when that will be.

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Even if it is unmanaged it should have an http interface (similar TP-link does) and an IP address.

Check with nmap -sP 192.168.1.2-254 if you have an unknown device, it could be the switch.

Edit: this model doesn't appear to have a way to display basic counters. As you said unplugging and replugging the ethernet cable is enough to restore traffic one workaround would be to use the vlan subsystem to disable and re-enable the port. Worked for me.

Answer 1

Hello,

Thank you for contacting.

May i know what is the firmware on the device?

Could you please draw a topology for your network how everything is connected and what are the IP addresses what ports are being used , how Rutx12 is connected with switch WAN(RUTX12) to LAN or LAN to LAN .

Rutx12 is getting internet from switch or its reverse?

Have you checked trying changing the cable?

Thanks.

Regards,

Ahmed

Comments

Hi,

I'm running what the router says is the latest firmware version.  I'm attaching a screenshot for reference.

Please see the topography below:

The RUTX12 is connected to the switch via the PoE ethernet cable attached on LAN1.  The WAN port is not used.

The RUTX12 is the internet connection getting the internet from one of the 4G LTE modems built into the RUTX12.

I have tried changing the cables, and it keeps happening.  I tried some other equipment (ZTE MF266 router) on the exact same cables and port on the switch, with no problems at all.

I changed the port on the switch, still the same problem.

The RUTX12 is housed in QuMax XR2 bi-directional kit for RUTX12

The connection going to sleep seems intermittent.  Sometimes it's fine for 8 hours, and then sometimes it has to be plugged in and out 3 times in 5 minutes. Once the LAN1 cable is unplugged and replugged in, the router is immediately available on the network.

If there is any other information you need from me, please let me know.

Regards,

John

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I had a similar issue, I don't know the reason why the link between the RUTX and the switch goes down but a workaround would be to shutdown the port the switch is connected to and re-enable it if a ping of one of the WRT3200ACM fails.

1) add a cron job to be run every minute:

*/1 * * * * /bin/ping -c 1 192.168.1.2 || /root/resetlink.sh

2) resetlink.sh (if connected to port 1, adapt if you need)

uci set network.@switch_vlan[0].ports = '0 3 4'

uci commit network

/etc/init.d/network restart

sleep 1

uci set network.@switch_vlan[0].ports = '0 2 3 4'

uci commit network

/etc/init.d/network restart

It would be simpler to affect an IP address to the switch itself and use it for the ping target.

It should be possible to do the same using the swconfig utility, however I don't know the exact syntax to perform a port reset.

Regards,

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Hello,

May i know if you connect Rutx12 from LAN1 to some other device , it works fine ?

How is Linksys and devices after linksys are connected? Link sys should be LAN(Rutx12) to WAN ( Link sys).

Thanks.

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The RUTX12 is in an external antenna housing on the roof of the building, and the only cable connected to it is LAN1 (with POE).  It works connected to other devices without a problem.

The Linksys routers aren't connected directly to the RUTX12.  They are connected to an unmanaged switch, which the RUTX12 also connects to.  The Linksys routers are connected in AP mode, so they shouldn't be LAN to WAN, but rather Linksys LAN to switch.

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As an update, I've turned off the DHCP on the Teltonika router and connected a Ubiquiti USG as the DHCP server for the last few days, and there has been no connection loss.  So, it seems clear that the problem only occurs when I have the DHCP enabled on the Teltonika router.

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Hello,

Could you try to directly connect one of the device(Not switch) with Rutx12 port directly ? when DHCP is enabled.

Thanks

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I had it connected like this when initially testing, and this caused the same problem, unless I disabled DHCP on the RUTX12.

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Hello,

When that happens even if you would have PC set on static IP would still be unreachable? and only re-plugging the cable helps?

Link sys has DHCP enabled or disabled?

Please let me know.

Thanks

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When this happens, the router is completely unreachable even with a computer with a static IP address.  Everything else on the network with a static IP address keeps working.  The only thing that changes it is unplugging and replugging the cable, or resetting the RUTX12.

The Linksys routers are in AP mode, so it's not possible to enable DHCP on them.

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Hello,

May i know how did you figured if it doesn't have internet ?

The purpose of doing these tests are to know if LAN goes down, DHCP stops working or internet goes down.

If internet is down you will be able to see on RMS , whether the device is online or offline.

Thanks

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I never said that it doesn't have an internet connection, I said that I don't have an internet connection as my internet connection is provided by the Teltonika router.  But I still can't imagine how the remote system will have more detailed logs than the RUTX12 could have.

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Hello,

From remote system we you can download troubleshoot file for the device. Troubleshoot file will have logs related to the issue . What is causing the issue.

As of now you cannot download troubleshoot file because device gets unreachable after the issue comes up.

Thanks.

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I'll try set up RMS and see where that gets us.  But for now it seems like a faulty device to me.

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As an update, the connection still seems to freeze with DHCP disabled, it just takes longer.

In the mean time, I've set up RMS, so I'll just wait now for the connection to die and see what the logs then say.

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Hello,

Thanks for your tests .

Please download troubleshoot file from RMS once issue occurs.

Thanks.

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Hello,

I've been testing RUTX12 for over a week, DHCP enabled, powered via PPoE connected to switch with other devices. Not once it went down or became unreachable. Please try re-flashing clean firmware version (no keep settings) and reconfiguring the device, if it still goes down periodically, tell contact your distributor, or sales manager for RMA.

Thanks

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I've tried flashing the firmware without keeping settings.  Tried factory resets, tried changing cables, tried different hardware, and everything else that I can think of.  Every time I think it's fine because it's been stable for a few days, I get a day of 10+ connection losses in a few hours.

We've opted to return the item during the return period rather than risk an ongoing intermittent problem.  It's already taken far too many productive hours away.  Instead I'm going to try one of the Ubiquiti Unifi LTE routers as I've had nothing but good experiences with Ubiquiti so far.

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If you have already followed the steps then its i would suggest you to contact your distributor for RMA.

Thanks