[CentOS] Large scale Postfix/Cyrus email system for 100,000+ users

[Les Mikesell]

Christopher Chan wrote:

>>>> I thought the usual ways of doing this were to either use a 
>>>> high-performance NFS server (netapp filer...) and maildir format so 
>>>> you can run imap from any client facing server, or to keep the 
>>>> delivery host information in an LDAP attribute that you find when 
>>>> validating the address.
>>>>
>>>
>>> This is the 'I have the money' way of doing this ;-)
>>
>> There are at least 2 free ldap servers.  Or if you are stuck with 
>> mysql you can probably add your own field for delivery host.
> 
> The service provider I used to work for tried openldap in 98. They got 
> burned big time. Maybe it is up to the task today. What kind of 
> hardware, though, would you use for one that the OP indicates will get a 
> lot of writes? Everything I have read says LDAP is not for high write 
> problems.

1998 was a long time ago.  Red Hat (fedora) directory server has claimed 
  good performce for several years now.
http://directory.fedoraproject.org/

But the openldap guys think they are better - see page 33 of the pdf 
linked from this page: 
http://www.mail-archive.com/ldap@umich.edu/msg01151.html
(22000 queries/sec, 4800 updates/sec on a terabyte database with 150 
million entries - but I think the test box had 480Gigs of RAM...)


>> Does anyone have enough faith in a free NFS server to use it in this 
>> scenaro these days?   How about opensolaris on top of zfs?
>>
> 
> I would say. No comment on opensolaris in this scenario but I am happy 
> with zfs as an offsite online backup solution.

Are you using the incremental send/receive operation for this?

-- 
   Les Mikesell
    lesmikesell at gmail.com