[SOLVED] Network going out momentarily during switch to backup generator

[RyanJK]

During our generator tests the network flickers and we lose connection to our server briefly, we have several network drives that are used for crucial processes.

The server resides in the same building as most work stations.

My question is why would the network be affected if the server never loses power. I think it could be the ethernet ports throughout the building are being affected.

Any help would be greatly appreciated, thanks in advance.

 

[jay32267]

I'm not real surprised.
During a generator test....it can be common for the line voltage to drop....generally very briefly.
This is generally during the time between the power cutting out and the generator kicking in.
If the voltage drops too far...you can see what you are seeing.

 

[Wacabletech06]

During our generator tests the network flickers and we lose connection to our server briefly, we have several network drives that are used for crucial processes.

The server resides in the same building as most work stations.

My question is why would the network be affected if the server never loses power. I think it could be the ethernet ports throughout the building are being affected.

Any help would be greatly appreciated, thanks in advance.

The flicker is likely rebooting at least once devise in the system, large switch, modem, whatever. Try some battery backups on major components to counter the flicker when it switches over. Although a minute is nothing compared to a full outage.

 

[RyanJK]

a minute is nothing compared to a full outage.

Thanks a lot! Just trying to see if there was a way to eliminate the downtime completely, we run some long processes so it would be nice.

 

[bill001g]

If you do not have both UPS and generator it is a poor design. Many data center generators take a few second to even minutes to fully stabilize. I was told that this was not so much for the servers etc but more for the AC units.

In any case the correct design is you use a UPS as the primary backup. When the power goes out the UPS immediately switches to battery. After some small period of time to allow for very small power outages you start the generator. After the generator has run for a period of time the UPS will switch off battery. When the main power is restored depending on the system it may go to UPS battery to avoid a momentary hit while the power moves.

If I would ever need to do this in my house my UPS run long enough that I could drag my generator outside and get it started before I drop off battery.

 

[RyanJK]

If you do not have both UPS and generator it is a poor design. Many data center generators take a few second to even minutes to fully stabilize. I was told that this was not so much for the servers etc but more for the AC units.

In any case the correct design is you use a UPS as the primary backup. When the power goes out the UPS immediately switches to battery. After some small period of time to allow for very small power outages you start the generator. After the generator has run for a period of time the UPS will switch off battery. When the main power is restored depending on the system it may go to UPS battery to avoid a momentary hit while the power moves.

This is how our setup is at the minute, and we're still experiencing a brief network outage.

 

[bill001g]

There is likely some device not plugged into the UPS.
I sometimes forget and plug things into the surge slots in my UPS rather than the battery backup.
Now there is a slim possibility that some equipment is very sensitive to the UPS cut over time. Unless you have a very expensive UPS it actually run on city power and switch to battery. You can normally hear a load click when it does this. In general the power supply in a PC stores a small amount of power in the capacitors and can tollerate tiny outages. Other equipment with smaller power supplies does not. My laptop power supply takes quite some time for the LED to go out after I unplug it both from the laptop and the wall.

I would still look for something that is not UPS protected by mistake.

You could get what is called a online ups where the power is always charging the battery and the battery is always providing the end equipment power. These are very expensive compared to the more common standyby UPS

 

[kanewolf]

Check the uptime on all your network devices. If you have a network monitoring program, like nagios running, add uptime to the things it monitors and put an alarm on uptime less than 10 min.