On 7/8/21 14:29, Saku Ytti wrote:
Network experiences gray failures all the time, and I almost never
care, unless a customer does. If there is a network which does not
experience these, then it's likely due to lack of visibility rather
than issues not existing.
Fixing these can take months of working with vendors and attempts to
remedy will usually cause planned or unplanned outages. So it rarely
makes sense to try to fix as they usually impact a trivial amount of
traffic.
Networks also routinely mangle packets in-memory which are not visible
to FCS check.
I was going to say the exact same thing.
+1.
It's all par for the course, which is why we get up everyday :-).
I'm currently dealing with an issue that will forward a customer's
traffic to/from one /24, but not the rest of their IPv4 space, including
the larger allocation from which the /24 is born. It was a gray issue
while the customer partially activated, and then caused us to care when
they tried to fully swing over.
We've had an issue that has lasted over a year but only manifested
recently, where someone wrote a static route pointing to an indirect
next-hop, mistakenly. The router ended up resolving it and forwarding
traffic, but in the process, was spiking CPU in a manner that was not
immediately evident from the NMS. Fixing the next-hop resolved the
issue, as would improving service provisioning and troubleshooting
manuals :-).
Like Saku says, there's always something, and attention to it will be
granted depending on how much visible pain it causes.
Mark.
