[wplug] OT - request for comment on an idea

[Chris Romano]

I guess this is OT because it doesn't direct discuss F/OSS but it will
involve F/OSS apps.

I am trying to create a BC/DR plan and I have an idea about a failover
web/email server for my company but would like some comments on it
from the group.  There is more insight and experience on this list
that I could get through reading stuff from google and what not.

Currently we house our web/email/db servers here in-house and verizon
does our DNS.

I would like to manage our DNS internally and not have verizon host
it.  I would setup two DNS servers; one server will be here (primary)
and the second one will be at an off-site datacenter (secondary).

On the secondary server I want to have a copy of our website/db/email
systems.  The services will not be running by default but will have
up-to-date data.  The reason for this is, I want a heartbeat between
the primary and secondary servers.  If secondary DNS detects the
heartbeat is down, it will start the web/db/email daemons and load new
zone files that point to itself for our website and email.  This way
if our circut goes down, our site will still be accessable.

Now from my understanding if a DNS server can contact the primary DNS
of the site/name that it is looking for, it will try the secondary DNS
for that site/name.  Is this right?  If so, this means that there
shouldn't be to much downtime if this where to happen.  I problem is
if the IP is cached on the requesting DNS server.  I am not too
familiar with DNS yet, so in this case will the site be down until the
requesting DNS server refreshes it's cache?

So is there a better way of doing this or am I at least somewhat on
the right track?  I hope that I explained that well enough.

Thanks,
Chris