cross connect reliability

Thu Sep 17 22:17:46 UTC 2009

From: Michael J McCafferty <mike at m5computersecurity.com>
Organization: M5Hosting
Date: Thu, 17 Sep 2009 14:45:36 -0700
To: nanog <nanog at nanog.org>
Subject: cross connect reliability

All,
 Today I had yet another cross-connect fail at our colo provider. From
memory, this is the 6th cross-connect to fail while in service, in 4yrs
and recently there was a bad SFP on their end as well. This seemes like
a high failure rate to me. When I asked about the high failure rate,
they said that they run a lot of cables and there is a lot of jiggling
and wiggling... lots of chances to get bent out of whack from activity
near my patches and cables.
 Until a few years ago my time was spent mostly in single tenant data
centers, and it may be true that we made fewer cabling changes and made
less of a ruckus when cabling... but this still seems like a pretty high
failure rate at the colo.
 I am curious; what do you expect the average reliability of your FastE
or GigE copper cross-connects at a colo?

Thanks,
Mike

    Does the colo let anyone run cables or do they have approved
contractors?    It sounds like a design issue to me in the way the cables
are treated.  In 4 years at a busy colo we have had one copper cross connect
not act right.  It would pass data but was flaky.  We replaced it because it
was an easy run just to rule it out.

    I am assuming your are in shared space.  If so I would investigate your
weak points (which I am sure you already are doing).

    Justin