[Dovecot] Load Balancing and HA

[Romer Ventura]

Hello,

 

I've been thinking about the best way to achieve load balancing and making
my mail servers highly available. So far I believe I have 2 scenarios:

Scenario1: This should allow any to lose any of the servers and clients
still have access to their emails (although I am not sure how the indexes
would react to this and sudden disconnection)

-          2 Dovecot Proxy servers, using a virtual IP to where the clients
will connect to from the WAN and LAN

-          2 Dovecot+Postfix servers with local cache

-          2 NFS servers and synced with dsync (mirror, 1 server writes to
its own NFS and changes synced to the other via dsync)

 

Scenario2: Pretty much as above on the back end. However, with this there is
no way to load balance users.

-          2 Dovecot+Postfix server with local cache

-          2 NFS servers synced with dsync

-          Make use of DNS MX record priority to provide access to secondary
email server

 

 

Anyone care to comment?

 

Thanks.


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