The Loop

Yesterday was a LONG day at work.  There was something wrong with our network.  It is tough for anyone to work when all of their information is in the cloud and they can't get to it.
 
Initially, I thought the first occurred during the heavy storms of Sunday night.  I was not at work on Monday and it was reported to me that the internet worked intermittently and they were able to work, at a much slower pace.

Upon arrival, I noticed that we had no wifi in addition to the slow, wired network access.  After eliminating many causes of the problem, I decided to focus on the switches.  (Hey if a bad switch can take down an entire airport, then I think it could happen to us.)

Fortunately, the switch was located that was causing the problem.  We then isolated the machine and followed it to the room where we found that there were two sources going to the same switch, creating a loop.  For those of you who don't know what that is I found this easy explanation on Dummies.com " ...This process will be repeated thousands of times per second, causing a huge volume of traffic from a single broadcasted Ethernet frame. When this happens on your network, everyone will lose the ability to communicate on the network, and the activity lights on your switches will be solid (on) rather than blinking (on and off). If you break the loop, your network will return to normal in a few minutes. "