On 20-Oct-99 Russell Nelson wrote:
> Arnold, Josh A. writes:
> > Based on everything I've been able to gather, the ultimate solution
> consists
> > of multiple qmail servers accessing a NetApp filer via NFS.
>
> Not completely obvious. It might be more efficient to have a server
> dedicated to a subset of the mailboxes, and for the smtp front-ends to
> run a variant of qmail-qmqpc to queue the mail on the appropriate
> machine based on the recipient. I don't know -- I haven't yet had a
> customer who needed that kind of solution who was starting from
> scratch. Most of them have found that sendmail simply isn't up to the
> task of dealing with more than a few tens of thousands of mailboxes,
> and want me to transition them to qmail.
big mail systems have two classic archs:
- single (or multiple) nfs store with multiple frontends: in this case all the
frontends view all the mailboxes, and the client can use any one to access
his mail. the botleneck here (assuming bandwith is no problem nor is horse
power) is the cdb/database to store the user info. It get's big. Ldap is the
solutiong here. So, Netapps (two with the mirroring option), gigabit
interconnnection with jumbo frames, alteons to loadbalence the frontends,
and ldap to store the user info (use several ldap boxes and loadbalance them
with alteon gear also) should get you to 1m users no probs.
- distributed arch based on nodes simmilar to the previos setup. the entry
point, a coupple of boxes alteon load balanced, redirects the user to the
proper none. Scalability probs: bandwith only, imho.
ldap is king as you can see... use as soon as you can, and growth should not be
a problem.
---
Pedro Melo <[EMAIL PROTECTED]>
IP - Engenharia de Rede <http://ip.pt/>
Av. Duque de Avila, 23, 1049-071 LISBOA - PORTUGAL
tel: +351 21 3166740/00 (24h/dia) - fax: +351 21 3166701
