This is my first venture into "fault tolerant" file systems, so 
bear with my coverage of some "basics".

I'm looking to re-implement the mail service for my company's two
offices. We currently have a single machine receiving and serving 
all mail. My theory is looking something like:

Site 1                                      Site 2
------                                      ------
MTA gateway                                 MTA gateway
(and coda client)                           (and coda client)
   |                                           |
   |                                           |
MTA server                                  MTA server
(coda client     / coda volume(s) for \     (coda client
   and           |                    |      and
coda server)     \ maildir storage    /     coda server)

Both sites have T1 Internet connections, which will provide the
IPsec connection for the two mail servers.

Q1: Can T1 speed adequately support two Coda servers?

Current size of the maildir's is 21 GB, but growth is expected.

Q2: What are practical size limitations of Coda volumes?

The general goal is redundancy (of course). If Site 1's T1 is down,
Site 2 still has access to e-mail, as do any remote users.

I guess I'll work out more details later - backups, performance, 
and so on...

Thanks,
jerry