[OpenAFS] Further TransArc -> OpenAFS musings/planning

Joe Di Lellio joed@ucsc.edu
Wed, 16 Aug 2006 11:57:36 -0700 (PDT)


First of all, thanks to all who've responded, especially John Harris,
Brian Sebby and Jeffrey Hutzelman.

It looks like mixing the TransArc & OpenAFS fileservers isn't going to
be an issue - good, as less trouble is always nice.  I'll just bring the
new systems into the mix and vos move stuff over.  Since I can do this
anytime, pretty much, I'll just take care of it as I have time for it
over the fall quarter.

The DB servers, though, I'm a little concerned over.  We're about to have
a week or so 'quiet' period here at UCSC, and I was going to snag a time
at the beginning of that to do the DB server swap.  Two ways I was
thinking of doing it:

1) Bring all the old servers down.  Copy over DB & others files to new
systems.  Swap in the new systems IP/hostname wise & bring them back up.

This approach is what John Harris et al suggested, and looks to be pretty
quick (he estimated 20 minutes - I'll assume twice that since I'm hyper-
careful/paranoid/take a lot of time on things I haven't done before).  It
does mean my pack of three DB servers are completely offline for this
time, but it's our normal service window during the mentioned quiet time.
I'll have the old TransArc servers, re-ip'ed but kind of as living backups,
should I need to get something.  Nothing AFS, even as a client, would be
running on these old DB servers.

2) Bring in the new DB servers, one at a time, and phase out the old ones,
one at a time.

Jeffrey gave me advice on this, but the more I've thought about it and the
more folks have advised, this doesn't seem like a good idea.  It's less
impact in theory (the cell isn't down), but the potential for other
problems concern me.  If it was closer to our normal busy times of the
year I'd think of this option more favorably.


I'm leaning strongly towards option #1 for the listed reasons.  Is there
anything else I need to be concerned about beyond what I've mentioned?
I'm aiming for the morning of Sat Sep 9 for this swap, and I'll have the
DB servers ready shortly.  The week following will be for 'oopses',
however unlikely but just in case.

Thanks again, all.  I'm far less nervous about this then when we first
started talking about this upgrade.

Joe

------
It ain't what you don't know that gets you into trouble.  It's what you
know for sure that just ain't so.		-- Mark Twain