Local SMTP/POP3-wise, the Imail "Peer Server" function will help you accomplish this.  You set your Imail servers up to "overflow" to each other, after segmenting your user base across the servers (you can use a round-robin algorithm when creating the SQL statement that creates accounts).  You can even share the same SQL database if you want -- just use different tables.  This way, if a load-balanced request comes in for a given POP3 account that isn't actually hosted on the destination server, it will search the cluster and redirect the traffic.  Note that the TCP/IP traffic is still routed through the destination server (it doesn't actually get redirected, HTTP-style), but you save disk I/O and actual SMTP processing.
 
Remote SMTP-wise, you don't really need to do anything except point clients to the cluster address.  You may want to give each box the same primary hostname to avoid Reverse DNS issues.
 
Overall, it's partially manual and partially automated, but it works.
 
Sandy
-----Original Message-----
From: Zerbe, Dean <[EMAIL PROTECTED]>
To: '[EMAIL PROTECTED]' <[EMAIL PROTECTED]>
Date: Tuesday, May 02, 2000 6:14 PM
Subject: [IMail Forum] IMAIL 6.03 How do I Config to load balance behind a Cisco 6509

My company is running a Cisco powered network. with 2 Cisco GSR's  those are connected to 2 6509 switches.  the Cisco 6509 has the ability to do load balance.  the hardware I am using allows 2 Ethernet ports to be connected for each server to theoretically do 200mbps full duplex.  this network is fully fault tolerant
 
Now the Question....
 
How should I configure IMAIL or should I bother?
 
 
My possible concept.
 
 
run 4 or more front end IMAIL servers load balanced from the Cisco 6509.  have those servers sync users by using a SQL 7.0 database.  have the directory structure point to a UNC  \\bigdiskserver\domainxyz.
 
 
then presto it all crashes because of open file issues? I don't know any ideas would help?  even other products you tell me
 
the SQL server and location for the file are in a Microsoft cluster server.
 
this is expected to hold 500,000  + accounts.

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