Unsafe Configuration Changes on Live Switch?

[astounding]

Hi,

What configuration tabs and specific config. items should be considered unsafe to change on an active switch (i.e. changes that will cause ports to drop power or drop connection or the switch to pause switching)?

I ask because this morning I made some changes to a WS-24-400A (Rev. B) running 1.3.9 on the Device>Configuration screen that I thought were harmless and completely unrelated to switch or PoE functionality, and noticed that all my PoE ports dropped. This is what I saw in the log:

Code: Select all

May 20 06:43:36 UI: Discovery_Ubiquiti: changed from 'Disabled' to 'Enabled'
May 20 06:43:36 UI: Discovery_Cisco: changed from 'Disabled' to 'Enabled'
May 20 06:43:36 UI: Discovery_LLDP: changed from 'Disabled' to 'Enabled'
May 20 06:43:47 switch[3662]: Detected cold boot
May 20 06:43:47 kernel: link state changed to 'down' on port 8
May 20 06:43:47 kernel: link state changed to 'down' on port 5
May 20 06:43:48 kernel: link state changed to 'down' on port 7
May 20 06:43:48 kernel: link state changed to 'down' on port 9
...


Could simply enabling Discovery cause the alleged "cold boot" here? And what is a "cold boot" anyway? It wasn't an actual boot of the switch from a powered off state. Logs for that look completely different.

Puzzled,
Aaron out.

[sirhc]

The switch CPU running the UI/CLI is a computer basically, sometimes on rare events weird things happen that normally do not occur.

There are many indivual applications running all the time on the switch CPU and if the right thing occurs at the wrong time you may get something weird happen on rare occasions. We do our best to prevent this but this happens on any piece of equipment.

I have been in IT work for almost 30 years and I have never found a piece of equipment that sometimes did not mess up or need rebooting.

Look your a WISP, what is your number 1 tech support call advice. "Can you reboot your radio"

What programs can I run on my computer that will "never" mess up?

We made a change to one of our switches last month which was enabling TFTP backup that caused a similar thing to occur. There was no rhyme or reason and we were unable to get the switch to do it again. That too was v1.3.9 on that switch of mine.

There were tons of bugs that have been fixed between v1.3.9 and v1.4.0

v1.4.0 is a much better firmware and we will be releasing v1.4.0 final probably later today.

All I can say is we do our best to prevent things like that but no matter what sometimes ODD things occur. If you can reproduce it we can fix it. But if it is an odd 1 in 1000 or more chances are if it gets fixed it is by chance that it gets fixed while fixing a know reproducible bug.

Hell they sent multi billion dollar machine to Mars and it messed up from a software bug.
https://en.wikipedia.org/wiki/List_of_software_bugs
http://www.scientificamerican.com/artic ... n-history/
http://www.computerworld.com/article/25 ... -bugs.html