>Inbound will be fine once I dedicate the current outbound box to inbound
>only.
>It's the outbound / ETRN that takes all of my resources.

outbound from the mailbox server is typically less than 20% of MX inbound 
to the mailbox server. so if two boxes can handle the inbound for your 
increased traffic, I don't see why two other boxes won't loaf handling your 
outbound

>My thought was 2 TigerDirect type servers dedicated for this task.
>Just not sure of the config...

They will build to spec. I have partner who bought a Tiger Direct Vision 
box for one his clients as an outbound gateway with me doing the admin.  I 
spec'd a Promise TX2000 for the ATA133 support of ATA133 drives.  ATA was 
stuck 33, until we figured out Vision had reversed the ATA133 cables end to 
end.  Now we are at ATA133.

>My thought was to have a second box to be able to balance the increased
>load.

if you have two boxes for load balancing, and one box goes down, then the 
remaining box has to be powerful enough to keep up with the entire load. 
ie, the box was carrying 50%+ of the load, now has to carry 100%

if you had 3 boxes, and one goes down, then the 2 remaining boxes increase 
their traffic from 33% to 50% of total.

the  point: 2 boxes is not a good load-balancing config unless each box it 
very powerful.

iow, if one box is not enough and you want to spread the load, you must had 
2 boxes (3 total, not 1 (2 total). ie,  you always need n+1 boxes, so when 
the "1" goes down the "n" can carry the full load.

>Processor of the day ofcource, what I need are the drive configs
>Can you define for me the config:
>         Controller suggestion / RAID type

If you stay with FreeBSD, then check the LINT file for supported SCSI 
controllers that do caching.  These boards are typically $500 to $600.

A lot of these controllers are 64-bit, 66 MHz PCI boards which would be 
happiest on an equivalent mobo.  This is for the mailbox server, not for 
the smtp gateways

RAID type is 1 for SMTP gateway.

for the mailbox servers, you will probably need striping and well a 
mirroring to get enough capacity for the mailboxes.

>and what channels are connected to
>which drives.

I see no value in internal $$redundancy of MX boxes.  The boxes are 
redundant at the box level.  the MX algorithm and DNS gives you inbound 
redundancy.

For outbound redundancy, Imail's "send all mail through gateway" doesn't do 
MX lookups, it does A lookups, so the MX algorithm doesn't help on outbound.

If you want dynamic load balancing for the outbound (or the inbound), then 
I have developed dynamic DNS scheme adapted to postfix (ie, it's "postfix 
aware".

Imail would send to the domain:

mxout.snipmail.net.  5m  ip.ad.re.ss

and my DDNS would change the ip.ad.re.ss to that of the gateway box where 
postfix is least loaded.   This includes NOT using the ip.ad.re.ss of a 
postfix box that has died.  Like a Radware Linkproof box, but a lot 
cheaper.  :)

Len


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