Last year I upgraded 10 of our busiest imail servers to RAID 0+1 on Intel SRCU42L controllers with 6 36GB U320 15k rpm drives. These machines have dual 1.2GHZ processors and 2GB memory. Whoah nelly, do they scream.. The real bottleneck is the drives. Initially the servers were running RAID5. We increased the throughput of the servers by at least 50% when we implemented the Raid 0+1. We handle over 60,000 users on each box with no problems. The real issue however is how much mail do you expect the server to process, not how many users there are. We had one server processing over 1 million incoming and 1 million outbound messages per day.
Raid 5, even a hardware raid 5 will slow down writes. You also want to turn off write caching on the raid controller.. You'll get better performance. Another word of advice, don't run mail off a SAN.. It needs its own separate array. Been there, done that, got the t-shirt and calls in the middle of the night. SANs are best for file storage and archiving, not active mailboxes. You're talking about having 1 mirror and 1 raid 5.. That's at least 5 disks.. Buy one more and a good 2U chassis that will hold 6 drives and a raid controller and do it all on one big raid 0+1.. That's just my opinion... But it's coming from 4 years running imail on at least ten different hardware configurations, and running more than just one server with more than a few hundred users. Thanks, Shad D. Pulley Sr. Systems Engineer IKANO Communications [EMAIL PROTECTED] 801-415-8023 -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Ed Dowdall Sent: Wednesday, April 28, 2004 12:31 PM To: [EMAIL PROTECTED] Subject: RE: [IMail Forum] setting up a 3000-user imail implementation Thanks John and Sandy. We're stirring up some strong opinions with my engineers on this end. Let me start by being clear. We're talking about HARDWARE RAID, not software. My understanding of when to use and not use RAID5 is that you want RAID1 for sequential file processing (like MS Exchange transaction logs) but RAID5 for all other processing, (like the OS and Exchange itself). That would agree with Sandy's comment "RAID5 is for read-mostly applications". Doesn't that also complicate large corporation efforts to install SAN solutions for their corporate data including mail servers? Or are there ways to make SAN solutions look like RAID1? Okay, so from the standpoint of Imail, how does this all fit in? I seem to recall that the .mbx files are sequential, so that would indicate the processing of incoming and outgoing mail might best be served by RAID1. But what about Microsoft 2003 itself, and the Imail OS and IIS and the 3000 users that are going to access and manipulate their mail? All of those things are "read-mostly" kinds of tasks. That would suggest that RAID5 would be the best thing for people using the system and the system itself, whereas RAID1 would be good for bringing mail transactions into and out of the mailbox files, and spool directory logs. Can these tasks be separated? Should the Imail directory (or even just the Domain and spool directories) be located on a RAID1 partition? And everything else on RAID5? Is that possible? Ed -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of John Tolmachoff (Lists) Sent: Wednesday, April 28, 2004 1:48 PM To: [EMAIL PROTECTED] Subject: RE: [IMail Forum] setting up a 3000-user imail implementation Others will chime in I am sure. Search the archives for hard drive configuration recommendations. True, Raid5 will hurt you a lot more than help. John Tolmachoff Engineer/Consultant/Owner eServices For You > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:IMail_Forum- > [EMAIL PROTECTED] On Behalf Of Ed Dowdall > Sent: Wednesday, April 28, 2004 10:30 AM > To: [EMAIL PROTECTED] > Subject: [IMail Forum] setting up a 3000-user imail implementation > > Hi all. > > I'm looking at setting up an imail implementation for 3000 users, all > webmail. I asked Ipswitch tech support if there were any white papers, > guidelines, or specifications for scaling but they said they've never > generated that sort of information. > They sent me to the forum... and so, I look to you, my peers for > guidance. > > Any thoughts about 3000 users? > Obviously, if I'm going to do it all on a single server, I'd want to > it to be as robust as is possible. I'm thinking Xeon, dual or quad > processor, coupla' gigs of memory, hard drives appropriate to 3000 > users at 20 megs a pop (total 60 gig). > > But is that the best approach? Is 3000 users too many for a single > Imail server? Are there scenarios where multiple servers are used? > If I did do multiple servers how would they be associated? Would I > have a single Imail user database located on one server, or simply > deal with multiple imail user databases separated logically by server. > Would the "unlimited user" license cover multiple servers or would I > have to get multiple licenses? > > One thing tech support did offer as advice was "don't use RAID5". This > seems totally wrong to me as redundancy and throughput are the primary > benefits of using RAID. Unless there's something bad about the way > Imail plays with RAID5? I'm talking hardware RAID. In fact, though I > can get 72 gig drives, I'm thinking it would be better to get like, > multiple 36's, just for the RAID-5 multi-processing benefits. > > thoughts? > > Thanks for your help. > > Regards, > > Ed Dowdall > > > To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html > List Archive: > http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ > Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
