Point noted: Do not run Imail and SQL on the same machine!
Korey
----- Original Message -----
From: "Daniel Donnelly" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, April 19, 2001 12:28 PM
Subject: Re: [IMail Forum] POP3 hangs w/external SQL database
> Korey,
>
> I think your conclusion is not 100% correct! Many others here in the forum
> have found that SQL is a resource hog and have recommended it _not_ be
> running on the same machine as IMail. Along with many other
recommendations
> for the hardware needs for the SQL machine. At least one user indicated he
> had separate machines and over 50K users and had no problems with IMail or
> SQL. That would seem to tell me, the ODBCUSER.DLL is OK.
>
> And your further information about POP logins to domains with and without
> SQL, seem to confirm that POP3 service is working fine. This would
indicate
> to me, that the problem is getting responses back from SQL, when POP3 asks
> for them.
>
> If you are happy with IMail DB, fine. If not, they I (using
recommendations
> sent by other forum members) would suggest you consider a separate machine
> for SQL and another for IMail. It sounds like your current machine might
> qualify for the SQL machine and maybe a less powerful one is needed for
> IMail, but that may depend on the number of users you have.
>
> Below is that other persons email:
>
> Subject: RE: [IMail Forum] For those using MS SQL
>
> I agree, SQL runs better on W2K, when properly configured! I have been
> following the SQL thread here for quite some time and, frankly, there is a
> LOT of mis-information going around. A couple of quick points if I may.
This
> is long but, I had to say it....
>
> First, after Mike Nice was gracious enough to share his re-worked
> ODBCUSER.DLL, external database use with Imail and SQL servers became a
> reality. Thanks to Ipswitch for incorporating that code in recent
releases.
> While some work still could be done in the multi-threading area, it works
as
> is.
>
> Second, the one biggest and most important performance issue when using
> Imail with an external database and SQL is NOT the Imail box, it's the SQL
> box and it's network connectivity.
>
> I know, your saying "but I've got a Pentium 4 and a zillion megs of RAM,
> etc..." and it still does not work.... Well, lets look at a few issues
> shall we? First, never, never, never (did I make that plain enough?) run
> SQL on the same machine as Imail, just don't do it, SQL running with Imail
> will seriously degrade Imail's performance, that's just the nature of
> database servers, they want it all... Let them have it all, run SQL on
it's
> own server, nothing else running with it.
>
> Hows your network working? Are you running in a switched Ethernet
> environment? You should be, 100mbs, full duplex. Do you monitor LAN
traffic?
> You should. If your still running 10mbs, half duplex through standard
hubs,
> UPGRADE! The Imail box and the SQL server can only process packets as fast
> as they arrive. Remember, Ethernet trashes packets when they collide and
has
> to resend. The higher the collision rate on your LAN, the lower the
overall
> performance. Get a switch, buy some new 100 mbs cards and join the new
> century...
>
> How's your SQL box configured? A fast processor won't help if the RAM is
> not there or, the I/O and disk access is slow. Avoid the temptation to
buy
> huge IDE hard drives, drive access time suffers, no matter what the
> manufacturer says. Run SCSI, boot from IDE if you must but, use SCSI
drives
> for SQL and it's data. And about RAM, 500 plus megs, PC 100 or higher
DIMMS,
> no SIMMS, run at processor bus speed, especiall on the SQL box, period.
>
> Beware of RAID! There are some cheap RAID controllers out there that will
> severly slow performence in RAID 5 configurations. Sure its nice to have
> RAID 5 but, count on the overhead to slow you down. Again, if you must use
> RAID, spend the money for a quality controller.
>
> Is your NT on W2K installation tuned for best performence? Foreground
apps
> should have minimum priority (performence boost) and background and
server
> apps should have maximum. Set up for maximum boost for "networking apps",
> not "file sharing" and certainly not "load balancing"
>
> Even if you have all the RAM in the world, increase your swap file size,
NT
> will still use it and bigger is better. A general rule of thumb is to
double
> whatever NT recommends.
>
> Having run Imail servers since version 2 (i believe, long time ago) we
have
> found the software to be quite stable and resilant, if you give it a fast
> environment to work in. If you have the means, test the time your SQL box
> takes to authenticate a database request. Anything over 20ms is telling
you
> something is wrong! We have found that, SMTP AUTH especially, will fail or
> severly degrade if it does not get an IMMEDIATE answer from the SQL
server.
> Consider this when pulling you hair out because users are getting a
password
> request box when sending mail using SMTP AUTH.
>
> Oh, and how's your PDC performing? If it running over 25% utilization for
> any 30 second period, upgrade it! Remember, an NT network is only as good
as
> all the machines that make it a network, PDC and BDC's included...
>
> That's, it, flame away but these observations come from running Imail and
> SQL in a 50,000+ user environment on all kinds of hardware and network
> topology.
>
> Robert J Fehn Sr. CEO, Senior Engineer
> ProNet USA Inc. www.pro-usa.net
>
>
> Daniel Donnelly
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