Switch hung after tagging a port in vlan

[snakebit31]

I have a ws-12-250-dc this morning i turned the poe off on port 6 and turned poe on on port 5 save config and everything worked great. Went to the remote location to adjust the antenna and i forgot to tag port 5 with my vlan, so i tagged it and then saved config and the the switch hung with no switching activity put had poe. So i drove to the switch location and all the poe port that was turned on before it hung was on but no lan connectivity on any port even when I plugged the laptop into it, so I cycled the power to the switch and then the only light I have is the power light. Has anyone came across this issue? What can I do to get the switch back up and running? I did notice when the laptop is plugged into a port when i cycled the power on the switch the switch port that im on would light up for a second and then go out. This switch was up for 150+ days without issues.

TIA, Craig

[mike99]

Seem to have nothing to do with the config change. It seem more a hardware issue. I would try to check what happening via serial port first. If it's software, you should be able to reset it and push back old config but it's probably hardware related.

[snakebit31]

@mike99 Thank you for the reply, I was going to try the via serial tonight before i sent a rma request. Just shocked me that it happened in the manner that it did. I will let you know what I find.

[mike99]

Problem normally happen on change. By exemple, the switch could have been ok running on RAM but hang while trying to write config change to flash ROM. If ROM is broken, switch won't be able to boot.

[Julian]

I think Mike's on the right track, but I can usually get these types of units to come back by doing the old unplug-and-plug on power and then holding the reset button down for a minute or so while it's booting. Will wipe your config, bring a backup along.

I'm not 100% on why they do that sometimes, but i think it has to do with a flash sector going bad (which is a normal thing) and not recovering within the flash's MBR equivalent? (this part isn't normal)

[snakebit31]

Yes unplugging the power and then booting it up with the reset button fixed it! I had a rma issued but tried this before i sent it in. Thank You!!!

[RebusCom]

I think Mike's on the right track, but I can usually get these types of units to come back by doing the old unplug-and-plug on power and then holding the reset button down for a minute or so while it's booting. Will wipe your config, bring a backup along.

I'm not 100% on why they do that sometimes, but i think it has to do with a flash sector going bad (which is a normal thing) and not recovering within the flash's MBR equivalent? (this part isn't normal)

Re: WS-12-250-AC rev. F

Very similar to the OP, had two VLANs, one tagged and the other not. The tagging was moved from one to the other. Same result. Lockup with no recovery. Per syslog it appears the traffic stopped about one minute after the change. That implies the switch perhaps tried to revert back to it's prior config, unsuccessfully.

Why did this happen, and more importantly, how to prevent it from happening again? This was in production when it occurred. If bad memory is suspected, is there a way to test it?

[sirhc]

Do not know what happened but before I would consider hardware I would say more like a configuration issue.

What version of firmware are you using?

Would like to see what your VLAN tab looked like before you made the change and what change you made.

Messing with VLANs can cause traffic to stop.

Did you go to the switch and plug a console cable into the switch and see what was going on?

This is why there is a console port for this type of thing.

From the console cable you could examine the config and see what's going on.

[RebusCom]

V 1.4.7

Didn't have time to mess with a production unit. There was zero traffic on all ports and the switch was unresponsive to pings or http. Replaced it to get the network back up and brought it to the bench for diagnosis only to have it be unresponsive to any access as it would immediately hang on powerup.

[sirhc]

V 1.4.7

Didn't have time to mess with a production unit. There was zero traffic on all ports and the switch was unresponsive to pings or http. Replaced it to get the network back up and brought it to the bench for diagnosis only to have it be unresponsive to any access as it would immediately hang on powerup.

Not sure.
I would try holding the factory default button in when powering it on as described here:
viewtopic.php?f=6&t=409#p2398

Press the factory default button and hold for 20 seconds when powering up
This feature reformats the writable partition where the config is stored then recreates a new config with the default, this process is actually handled but the boot loader. If you ever see an error or warning on the console during initial boot or in the Linux system log about the JFFS2 filesystem such as a checksum issue this is the only way to correct that issue. Now the JFFS2 file system is pretty resilient and even if it gets corrupted 99.9% of the time you would never have an issue but if you really want the error message to go away you have to do this type of factory default, just remember to backup your config or write it down first as with any factory default your config is lost!

WHEN PERFORMING THIS DEFAULT YOU MUST LET THE SWITCH SIT FOR SEVERAL MINUTES

If no love then RMA it.