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

Thu Oct 25 02:30:36 UTC 2007
Christopher Chan <christopher at ias.com.hk>

Craig White wrote:
> On Thu, 2007-10-25 at 09:58 +0800, Christopher Chan wrote:
>> Les Mikesell wrote:
>>> 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/
>> Yeah, well, I guess the Fedora Directory server is unlikely to drop its 
>> entire datastore and will actually keep running but hey, are you going 
>> to migrate back to ldap if you have a system that is distributed across 
>> different mysql boxes running on cheap boxes and does its job?
> ----
> what I can't figure out is why you are asking questions when you have
> already decided answers...in part based on experiences from 10 years
> ago.

Well, I do not work for that service provider anymore...I was just 
putting forth the question they would probably ask...

In any case, the money for hardware stands I believe unless Fedora 
Directory/OpenLDAP has really good performance in a heavy read/write 
environment versus mysql.