Many thanks to:
rockwell_at_rch.dec.com
john_at_iastate.edu
stellr_at_smyrna.cc.vt.edu
bennett_at_hpel.umd.edu
pcemmeri_at_srp.gov
To my questions, I'm quoting rockwell:
"1) Is there a workaround to update DNS information on a secondary name server
when the primary is down?"
Not really, unless you want to mirror the zone files of the primary on some
other system, then re-configure (i.e. modify the named.boot) on the
secondary and restart BIND.
"2) Alternatively I was wondering about changing the secondary name server to a
second primary name server. However, the "DNS and Bind" book from O'Reilly
(1994 ed.) says on p.78, "You could set up another primary name server, but we
don't recommend it. You can always change a secondary name server into a
primary name server later if you decide that you want to expend the extra work
it takes to run multiple primary name servers." Other than a one-time effort to
automate keeping the data files in sync (via make, csh script or rdist), what
extra work is involved? Are there any disadvantages or drawbacks to running
multiple primary name servers on Alphas?"
No one mentioned any drawbacksk specific to Alphas.
"The extra work is keeping the zone files in sync. This has many implications.
First, when you make a change on one primary, and then you
distribute the new zone files, you need to signal the BIND named to reload
itself from the new zone files. You'll have to do this work on both
sides. You'll have to automate both sides to see if the files are the same
and push the one with the latest zone to the other system. Also, you have to
be aware of which system you should make any changes on. Guess what would
happen if two people make (different) changes to the zone files on each
system at the same time?
Even with a second primary server, the secondaries only get their zones
from *one* primary. If you're pointing to a primary that goes down, you
need to reconfigure your named.boot file to point to the other secondary,
then restart named."
Many thanks!
Kevin McGuire
Lattice Trading
617-832-1809
Received on Thu Dec 21 1995 - 22:12:58 NZDT