email/colo -- amazing response... thanks...

[mark at buttery.org (Mark J. Dulcey)]

Chris Devers wrote:
> 
> The downside is that the storage requirements on the mail server can be
> huge, depending on people's habits, but if you have a policy of making
> users transfer mail to local storage or removable media [cd, tape] for
> archiving then it's not so bad. 

But hard disk space is cheap... put a couple of 200GB drives in the 
server as a mirrored pair, and you're probably set for a while, at least 
as long as you make sure people don't store huge attachments on the 
server. And you have the data security of the mirroring. Also, it's 
easier to do backups if your organization's policies call for backup of 
email, or to enforce policies of purging old messages. (Some 
organizations are required by law to keep long-term records of email 
messages. Others actively avoid long-term storage of them.)

If you are planning to do backups of an email server, you'll want to 
choose one that stores the messages in maildir format rather than mbox 
format. An incremental backup of the former will only back up the new 
messages, but a similar backup of the latter would be just about the 
same as a full backup of the server, since each mbox would change every 
time that user gets a new message.