WS-12-250-DC random reboot!!

[Banana Jack]

Thanks sirhc - at the moment I'm suspecting that a network loop and/or bad plug/cable/radio is to blame... Today I've been enabling loop protection on selected switches and it seems to be pointing me toward a certain part of the network based on the ports on which loops are being detected. So maybe I'm making some progress.

Just to update you sirhc and anyone else who's interested for the record: this problem turned out to be an apparently faulty Mikrotik S-85DLC05D SFP module which was in our main WS-26-400-AC switch. Wireshark showed a broadcast spike (2000-3000 PPS) every minute and sometimes with additional smaller spikes in between. Swapping out the SFP module immediately cured it - screenshot attached.

The Netonix 'Loop Protection' feature was useful in showing up the problem and mitigating it in some parts of the network (to the detriment of the downstream parts), although sometimes the port that it reported as having the problem led me up some blind alleys. It was only when I tried setting Broadcast Storm Control to 2K on our main switch that the switch freaked out, crashed (with syslog kernel err FAIL: RX Alloc 1866 bytes) and when it came back up, the SFP remained down. I had to plug/unplug the SFP several times to get the link up, so then I became suspicious and swapped it out, which then cured the broadcast spikes according to Wireshark's extremely useful Statistics > I/O Graph feature. Hopefully our switches will now stop watchdog-rebooting.

Thanks
Glenn

[sirhc]

I also started to experience random reboots on WS-12-250-DC. 1.5.0

It happen right after I added two additional devices and maxed out this switch ... 11 ports are 24v and one port is 48HV. I started to think that maybe there is too much power draw on the 24v bus. How can we find the real cause of the reboot ?

Well older WS-12-DC / WS-12-250-XX / WS-12-400-AC units did have a 24V budget of about 106 watts, these models today have a 24V budget of 160+ watts.

This is discussed here in great detail: viewtopic.php?f=17&t=3934#p24989

[sirhc]

Thanks sirhc - at the moment I'm suspecting that a network loop and/or bad plug/cable/radio is to blame... Today I've been enabling loop protection on selected switches and it seems to be pointing me toward a certain part of the network based on the ports on which loops are being detected. So maybe I'm making some progress.

Just to update you sirhc and anyone else who's interested for the record: this problem turned out to be an apparently faulty Mikrotik S-85DLC05D SFP module which was in our main WS-26-400-AC switch. Wireshark showed a broadcast spike (2000-3000 PPS) every minute and sometimes with additional smaller spikes in between. Swapping out the SFP module immediately cured it - screenshot attached.

The Netonix 'Loop Protection' feature was useful in showing up the problem and mitigating it in some parts of the network (to the detriment of the downstream parts), although sometimes the port that it reported as having the problem led me up some blind alleys. It was only when I tried setting Broadcast Storm Control to 2K on our main switch that the switch freaked out, crashed (with syslog kernel err FAIL: RX Alloc 1866 bytes) and when it came back up, the SFP remained down. I had to plug/unplug the SFP several times to get the link up, so then I became suspicious and swapped it out, which then cured the broadcast spikes according to Wireshark's extremely useful Statistics > I/O Graph feature. Hopefully our switches will now stop watchdog-rebooting.

Thanks
Glenn

Thanks for the update.

Look, most any switch will reboot and do weird things with loops, not just Netonix. I have been in IT for 30+ years and loops and broadcast storms have always caused problems with any network device I have ever worked with.

If IT work was simple then we would all be out of a job because everyone has a friends whose 12 year old son is a computer GENIUS - I CRINGE EVERYTIME SOMEONE SAYS THIS. If they are such a genius then why are you standing in my shop with your computer telling me I should fix it for no more than $25, take it to the 12 year old GENIUS.

[Banana Jack]

Couldn't agree more!!