I hit ctrl+enter a little too quick ... Web links, my favorite (and still what I consider the most comprehensive new-to-go page http://www.lifewithqmail.org/ldap/#Cluster (with a target to the clustering section, which isn't that comprehensive ... But does give a bit of detail on the idea)
Best suggestion, spend some money and get two "throwaway" pc's and test it out on them. I've seen throwaways going for nearly $88 bucks (for 166mmx's) so that should be similar in dm. If I find the page I saw ages ago with heaps of clustering info, I'll send it to you. -----Original Message----- From: Kosh Naranek Sent: Tuesday, 12 March 2002 01:32 To: [EMAIL PROTECTED]; [EMAIL PROTECTED] Subject: RE: high availability solution? I'm going from memory, but this is what I remember from testing and man/faq pages. The Clustering mode is more for if you need to have many servers for a huge amount of mailboxes, if you have userA and userB on serverA and serverB respectively, if mail fails to be sent to userA externally and serverB gets it, it will forward it on, if userA pops into serverB, then serverB just forwards the pop connection to serverA, so if serverA is down then that user can't get their mail Basically clustering allows many servers to work together, but still are independent when it comes to mailboxes (which is good, imagine if mailboxes were replicated, or worse, striped across multiple hosts ....) -----Original Message----- From: manfred [mailto:[EMAIL PROTECTED]] Sent: Monday, 11 March 2002 21:52 To: [EMAIL PROTECTED] Subject: high availability solution? Hi everybody, I have a little understanding question to qmail-ldap. I haven't found an answer to this in the documentation yet, so I'll give it a try here. I'm running qmail-ldap without clustering enabled and it works really nice. Now I want to have a second server installed for the case, that the main server has to be maintained or is going down. As I understand (please help me if I'm wrong here which I certanly might), qmail-ldap has clustering support which is designed for load-balancing in the first place. So, when cluster-members receive pop3 sessions, they try to hand it over to the mailHost cluster-Server, right? But what, if this one is down? Does the session end with an error for the pop user? I assume, that smtp sessions (local delivery) will work and the cluster-member tries to connect to the mailHost cluster when it's up again to sync the maildirs, or am I wrong? So another way would be, to have a second MX entry, which would be fine for 'hot-standby' of the second server, but let's assume the case, that a lot of mails get handled locally in the time, the first server is down. Then, how is it possible to have the mails delivered from the second server to the first, so the maildirs of the first server have all the mails (because ongoing pop sessions will be handled by the first MX again)? I would really appreciate some hints on this topic, maybe a good starting point in the web for further research, befor I try to configure 'something'. Thanks a lot. Manfred
