This is the blog of Ronald Bartels that wanders on and off the subject of problem management (that is how it started), but it is best described by Ray who says this is Daddy's thoughts! Like the best music is from the Eighties and a wee dram helps in solving most inconveniences.
Denying your spanning tree
As I suspected, the customer had disabled spanning tree due to
concerns about the speed of failover. They had also managed to patch a
layer 2 loop into their network during a minor change, causing an
unchecked loop to circulate frames out of control, bringing down their
entire cell site. I explained to them the value of STP, and why any outage caused by it
would be better than the out of control loop they had. I was told to
mind my own business. They didn’t want to enable spanning tree because
it was slow. Yes, I said, but only when there is a loop! And in that
case, a short outage is better than a meltdown. Then I realized the customer and I were in a loop, which I could break by closing the case. Newer technologies (such as SD-Access) obviate the need for STP, but if you’re doing classic Layer 2, please, use it.