Re: backup mail server help
Sorry, I forgot to include the list in the to... Any comments would be greatly appreciated, esp. in regard to nfs locking... Jeff, You make a very valid point, however this can be overcome in many ways. I am currently researching this for my employer. Here's a general overview of how I'm planning on designing our network/servers. --- - external net | | director1director2 | | --- - internal net | | | qmail1qmail2qmail3 | | | \___ | __/ \|/ | --- - gigabit 'nfs' net with backup 100Mb net || NFS1 NFS2 I'm looking at using LVS (Linux Virtual Server) to handle the load balancing/clustering. We'll be using the cluster for www/pop3/dns/etc as well. LVS will allow us to add machines dynamically. We'll be using qmail/ldap/ldap-control and 2 (or more) LDAP servers for qmail configuration. I've also considered having the cluster servers boot off of CD and use a single disk for /tmp and the queue. I haven't fully researched the NFS servers yet, but here is my idea. The developer that made ReiserFS also wrote/is writing DRBD, which is capable of doing network mirroring. I am planning to use 2 e450s that I have with Samba (for Win servers), NFS (mirrored with DRBD), and heartbeat software to control the failover between the 2 servers. There are 2 obvious alternatives to the NFS solution that I mentioned though. NetAPP makes an appliance (Filer) that can handle 6TB (RAID5) storage which provides for (according to some friends of mine that use them in a 75+ e6000/45+ win2k env) 5 9s of reliability. I don't have prices, but I've heard that one Filer can run $80k. The other option is a software solution (clustering/replication/failover) from Veritas, which comes highly recommended. DISCLAIMER: I don't work for any of the above mentioned companies. Would anyone be interested in helping me develop a FAQ for this? Cheers, Mike Jeff Palmer wrote: And if your NFS server goes down, both servers are useless. In which case, what was the point of having a backup server again? Jeff Palmer [EMAIL PROTECTED] At 09:57 AM 6/13/01 +0300, you wrote: Alternatively you can run two SMTP servers and one POP server. Do NAT for the two and export the partition with Maildirs(at the pop server) to the SMTP servers through NFS. The two servers seem to be one to the outside world. NFS can be insecure though. Joe. - Original Message - From: Henning Brauer [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Saturday, June 09, 2001 4:15 AM Subject: Re: backup mail server help On Fri, Jun 08, 2001 at 04:33:49PM -0700, Hank Wethington wrote: What I'd like to accomplish is if Server A is unavailable, then mail goes to server B. Once A is back up, server B sends the mail back to server A. Does On server B, add all domains in question to rcpthosts, but NOT to local or virtualdomains. That's it ;-)) -- * Henning Brauer, [EMAIL PROTECTED], http://www.bsws.de * * Roedingsmarkt 14, 20459 Hamburg, Germany * Unix is very simple, but it takes a genius to understand the simplicity. (Dennis Ritchie)
Re: backup mail server help
On Wed, Jun 13, 2001 at 06:03:41AM -0600, Jeff Palmer wrote: And if your NFS server goes down, both servers are useless. In which case, what was the point of having a backup server again? Which is why you deploy this with something like a NetApp filer, that lets you deliver to NFS, and have multiple external pop3 servers as well. (And have two NetApp's mirroring your data at the same time) Adam -- [EMAIL PROTECTED] - (http://sysadminsith.org) Evil Lord of the Sysadmin Sith Darth Rmdashrf
Re: backup mail server help
On Thu, Jun 14, 2001 at 12:42:28PM -0700, Adam Jacob wrote: On Wed, Jun 13, 2001 at 06:03:41AM -0600, Jeff Palmer wrote: And if your NFS server goes down, both servers are useless. In which case, what was the point of having a backup server again? Which is why you deploy this with something like a NetApp filer, that lets you deliver to NFS, and have multiple external pop3 servers as well. (And have two NetApp's mirroring your data at the same time) Or just being clustered on the same set of shelves which use RAID4 themselves, so one of each kind of part can go down :) Greetz, Peter -- Against Free Sex! http://www.dataloss.nl/Megahard_en.html
Re: backup mail server help
Alternatively you can run two SMTP servers and one POP server. Do NAT for the two and export the partition with Maildirs(at the pop server) to the SMTP servers through NFS. The two servers seem to be one to the outside world. NFS can be insecure though. Joe. - Original Message - From: Henning Brauer [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Saturday, June 09, 2001 4:15 AM Subject: Re: backup mail server help On Fri, Jun 08, 2001 at 04:33:49PM -0700, Hank Wethington wrote: What I'd like to accomplish is if Server A is unavailable, then mail goes to server B. Once A is back up, server B sends the mail back to server A. Does On server B, add all domains in question to rcpthosts, but NOT to locals or virtualdomains. That's it ;-)) -- * Henning Brauer, [EMAIL PROTECTED], http://www.bsws.de * * Roedingsmarkt 14, 20459 Hamburg, Germany * Unix is very simple, but it takes a genius to understand the simplicity. (Dennis Ritchie)
Re: backup mail server help
And if your NFS server goes down, both servers are useless. In which case, what was the point of having a backup server again? Jeff Palmer [EMAIL PROTECTED] At 09:57 AM 6/13/01 +0300, you wrote: Alternatively you can run two SMTP servers and one POP server. Do NAT for the two and export the partition with Maildirs(at the pop server) to the SMTP servers through NFS. The two servers seem to be one to the outside world. NFS can be insecure though. Joe. - Original Message - From: Henning Brauer [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Saturday, June 09, 2001 4:15 AM Subject: Re: backup mail server help On Fri, Jun 08, 2001 at 04:33:49PM -0700, Hank Wethington wrote: What I'd like to accomplish is if Server A is unavailable, then mail goes to server B. Once A is back up, server B sends the mail back to server A. Does On server B, add all domains in question to rcpthosts, but NOT to locals or virtualdomains. That's it ;-)) -- * Henning Brauer, [EMAIL PROTECTED], http://www.bsws.de * * Roedingsmarkt 14, 20459 Hamburg, Germany * Unix is very simple, but it takes a genius to understand the simplicity. (Dennis Ritchie)
backup mail server help
I think my mind is unstable from trying to figure this out on my own. I've got a main mail server (FreeBSD 4.3/qmail 1.03/vpop/sweb/imap/blah blah blah) and a second on a separate network (RH Linux 6.2/qmail 1.03/qmail-pop3d). What I'd like to accomplish is if Server A is unavailable, then mail goes to server B. Once A is back up, server B sends the mail back to server A. Does this make sense? I know about the MX records in DNS, but how do I make qmail accept the messages but not deliver them and eventually send them back to the higher priority server. Man I'm confused. Is this even possible? If its not why have different MX hosts? If it is, is my brain just too small to absorb the needed info. Will George Lucas make a decent Star Wars 2 or are we in for another bad story line? Ok.. let me put back on my strait jacket. Hank Wethington Information Logistics www.GoInfoLogistics.com mailto:info.at.GoInfoLogistics.com
Re: backup mail server help
On Fri, Jun 08, 2001 at 04:33:49PM -0700, Hank Wethington wrote: What I'd like to accomplish is if Server A is unavailable, then mail goes to server B. Once A is back up, server B sends the mail back to server A. Does On server B, add all domains in question to rcpthosts, but NOT to locals or virtualdomains. That's it ;-)) -- * Henning Brauer, [EMAIL PROTECTED], http://www.bsws.de * * Roedingsmarkt 14, 20459 Hamburg, Germany * Unix is very simple, but it takes a genius to understand the simplicity. (Dennis Ritchie)
RE: backup mail server help
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hank, on the backup just put the domains in rcpthosts file NOT in locals and NOT in virtualdomains this will effectively configure the backup mail server to accept mail and try to deliver it to the primary. Make sure your dns records are correct. you don't need qmail-pop3d on the secondary because it won't store mail you only need the qmail process and the qmail-smtpd process Thats all it's that simple Who ever said that configuring qmail was difficult? Willy De la Court Quint NS NV On Saturday, June 09, 2001 01:34, Hank Wethington [SMTP:[EMAIL PROTECTED]] wrote: I think my mind is unstable from trying to figure this out on my own. I've got a main mail server (FreeBSD 4.3/qmail 1.03/vpop/sweb/imap/blah blah blah) and a second on a separate network (RH Linux 6.2/qmail 1.03/qmail-pop3d). What I'd like to accomplish is if Server A is unavailable, then mail goes to server B. Once A is back up, server B sends the mail back to server A. Does this make sense? I know about the MX records in DNS, but how do I make qmail accept the messages but not deliver them and eventually send them back to the higher priority server. Man I'm confused. Is this even possible? If its not why have different MX hosts? If it is, is my brain just too small to absorb the needed info. Will George Lucas make a decent Star Wars 2 or are we in for another bad story line? Ok.. let me put back on my strait jacket. Hank Wethington Information Logistics www.GoInfoLogistics.com mailto:info.at.GoInfoLogistics.com -BEGIN PGP SIGNATURE- Version: PGPfreeware 6.5.3 for non-commercial use http://www.pgp.com iQA/AwUBOyFuT/4IaGw3x6aJEQIY3ACg5Ng800TSvSAnW24MNimBhe/3hN0An3Ty o8QVTaxyVI4wguaNXqADJR0Y =NBR6 -END PGP SIGNATURE-
Re: backup mail server help
Hank Wethington [EMAIL PROTECTED] wrote: What I'd like to accomplish is if Server A is unavailable, then mail goes to server B. Once A is back up, server B sends the mail back to server A. Okay. Does this make sense? Eminent sense. I know about the MX records in DNS, but how do I make qmail accept the messages but not deliver them and eventually send them back to the higher priority server. If a domain is in neither locals nor virtualdomains, qmail won't try to deliver it on the local box. To get qmail to accept mail for that domain via SMTP, put the domain name in rcpthosts. Charles -- --- Charles Cazabon[EMAIL PROTECTED] GPL'ed software available at: http://www.qcc.sk.ca/~charlesc/software/ Any opinions expressed are just that -- my opinions. ---
