Posted Mar 8, 2010 17:37 UTC (Mon) by jeremiah (subscriber, #1221)
In reply to: Code names by Baylink
Parent article: Fishy business
I never said I was trustworthy or that I could spell. Only that my life has been easier after moving
from code names to role based names, in a virtualized environment w/ one service per server.
Perhaps a hybrid approach would work best. With dns-1 and dns-2 as the hostnames and dns
as the CNAME? I realize that I'm beating a dead horse here, but let me continue anyway, since
this discussion will make me better at what I do, and therefor is more about understanding, than
arguing a point.
I have 40+ fibre channel LUNS, in most cases each LUN represents server/service. Each has a
number and WWN associated with it. I can map a WWN to a NAME which is represents a target
WWN. no DNS here. I also have FC switches which need mapping as well, zone names etc. I have
8 blades each of which has the ability to have 16 named LPARS. I also have wiki-documentation
for each complete mapping (IP,name,MAC,LUN,LPAR,VLAN,etc). The only thing that is constant in
this mess is the service that the machine is performing, and the IP address where it can be
found. Perhaps this is where the issue arises, in that in everyone else's experience, the IP
address and the Service are disconnected as well. When I bring a new replacement system online
I either copy it from a hardened clean copy, or the currently running copy, and run that LUN on a
different blade where I can test it etc. Then shut both the old and the new systems down, switch
the LUN mapping, and bring the new one up. This takes 2 - 5 min tops, which in my
environment, is fine. I don't have to change any DNS entries, logging, intrusion detection, etc. All
I have to do is change one entry on a fibre-channel controller.
After reading what I have written, maybe I am 'slicing' and 'dicing' but at a different level, than
CNAMES. Because my LUNS are just numbers that I can't really control. And If I could, they would
become DNS-1,DNS-2,DNS-3. I will say though, that when trying to diagnose a problem, it
helps immensely to have strict naming conventions on every piece and configuration.