Ubiquity<->Mzima routing loop

Mike Lewinski mike at rockynet.com
Sat Jul 19 02:42:09 UTC 2008

Paul Wall wrote:
> Isn't that what a routing loop is, when it loops back out to the
> transit/interface from which it entered?

Of course.

I think the sensitivity comes in to whether the diagnosis "routing loop" 
is one of the cause or effect.

"this routing loop appears to show a network problem"


"this routing loop is THE problem"

Loops could happen due to human error in creating duplicate static 
routes, which would often be the ISP's responsibility to fix. They can 
also happen when the end-user takes their network down for maintenance, 
which is something the ISP can't usually fix (short of providing a 
naildown to prevent the loop from appearing, which doesn't really "fix" 

I've been the recipient of angry emails accusing us of incompetence in 
cases where the customer had taken their network down intentionally. So 
we started putting in naildowns anywhere that might be likely to happen.

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