noob question multiple db files, soa's and mx records.

[Joe Oaks]

Hello guru's

I have been running bind for a little over 2 years now but don't fully
understand
it and how to configure it very well.

I started out with a single domain name, trells.com running mail, ftp, http,
the
standard stuff, no big deal. Now however we have multiple domains (mainly
web)
this too was no big deal. However this has grown to a need of having
multiple
mx records, and I'm unsure how to update this.

Each domain has its own db file and mx record, and this part was the part
that was
messed up and I'm trying to fix. We run qmail as our mail server and for a
while
this was fine one instance controlling all domains. I'm in the process of
setting
up a separate instance of qmail for each domain, and for that I need to get
my
dns setup correctly.

My question to you guys is this,
1) tc1.trells.com has multiple ip's, and I want to bind mail.trells.com to
   207.168.116.66 and mail.bazalar.com to say imp 207.168.116.67, but I'm
lost
   in how to do this in the db files. trells and bazalar each have there own
   db file.

Once I can get an understanding of how to do this I can then setup the mx
records.
Would I make the db.trells.com mx line like
a) @               IN      MX      10      mail.trells.com.
or
b) 207.168.116.66	IN	MX		10	mail.trells.com.

and then the db.bazalar.com mx line similar, using the actual ip instead of
the @?

I'm sorry for my ignorance, and I hope I have explained what I'm trying to
do, as
I have no other way of explaining it or searching for it :(

Joe

also on a side note, in the soa second line i.e.
trells.com.     IN      SOA     tc1.trells.com. mail.trells.com. (
for the other domains, i.e. bazalar.com what would I put here, since its the
same
machine?
bazalar.com.     IN      SOA     tc1.bazalar.com. mail.bazalar.com. (