[c-nsp] Parity Errors and Cosmic Rays

[John Neiberger]

Back in February, I had a VIP freak out in my 7513 due to a memory
parity error. TAC said that it appeared to be an isolated event and not
due to an actual hardware problem. It happened again in April and TAC
still said that it was most likely cosmic rays or something and not an
actual hardware problem. However, we replaced the hardware anyway just
to be safe.

Fast forward to this morning when the RSP4 in that router got a memory
parity error and rebooted. That is a spectacularly bad thing to happen
in our network considering what is attached to this router. Again, it
appears that it's "an isolated event, probably due to cosmic rays."

How many times do I have to see the same "isolated" event before I
start looking for other answers? I guarantee you that the CTO of our
company will not be pleased when the best answer I can give to him is
"cosmic rays".

Is this actually a common problem? Or at least common enough that I
should expect to see it every other month or so? It seems strange that
this router has run for years and we've never seen a memory parity error
and now we've seen three in three months.

Any thoughts?

Thanks,
John
--