Re: [vchkpw] vpopmail clustering examples
in my experience nfs has been less that reliable. What I was trying to do was have two independent systems that the database is in sync with. The nfs solves the problem but what happens if the nfs server goes down ??? and on a side note. in my experience nfs on Linux under a high load environment is not reliable. and I was using redhat 7.2. but this was my experience. nfs on sun in rock solid. I was trying to stay away from using nfs if possible. but I might have to go to that. and as always thanks for responding to my question sir. John - Original Message - From: Super-User [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Monday, December 30, 2002 9:32 AM Subject: Re: [vchkpw] vpopmail clustering examples Well, I don't have any examples, but here is what we are doing (using mysql for authentication): Ingredients: 2 qmail/vpopmail/mysql servers(load balanced) 2 mysql servers 1 nfs server Preheat the oven to 350... mysql: One mysql server is the primary, and one the secondary (the secondary is not necessary, but I wanted a 'warm' standby). In addition, the 2 vpopmail servers are running a local mysql daemon. The secondary server, and the 2 vpopmail servers are replication slaves of the primary. (For replication information, see the documentation on the mysql site, its fairly straightforward) nfs: The ~vpopmail/domains directory is nfs mounted from the nfs server. The /var/qmail/control directory and the /var/qmail/users directory are also nfs mounted. (I had some trouble getting nfs to work. In the mount options, I had to set anon=89 to get it to work properly) Vpopmail: Edit the vmysql.h header file so that the MYSQL_UPDATE_SERVER is the primary mysql server, and the MYSQL_READ_SERVER is localhost. I'm sure that you could set your read server to a remote host, but I think localhost would be faster, and it reduces network traffic. So basically, each qmail/vpopmail server is running its own queue. Mysql updates are sent to the primary server, and replicated through to the secondary, and the local mysql daemons. The Maildirs and the control files are on nfs to ensure that both boxes are as similar as possible. In the vipmap, for each domain we have the public IP, and the 2 private IPs set up. I'm not certain whether having the public IP in the map is necessary, but I don't think it hurts anything, so why not. If you are using cdb for authentication, my first suggestion would be to try mounting it over nfs so that all clients are working with the same info. This could cause some problems since multiple client's updates might stomp on each other. I'm not a cdb guru so maybe someone else has some input? By the way, in the near future, we're considering replacing our current Solaris nfs box with 2 Redhat boxes, using heartbeat for failover, with fibre channel for storage. Is anyone doing something similar with vpopmail or heartbeat? If so, any input? Thanks, Duane Wylie -Original Message- From: John Runnels [mailto:[EMAIL PROTECTED]] Sent: Sunday, December 29, 2002 8:40 PM To: [EMAIL PROTECTED] Subject: [vchkpw] vpopmail clustering examples is there anyone out there in vpopmail land that knows where there is any information on clustering or loadbalancing vpopmail. what I mean by this is having multiple copies of vpopmail running on more than one server. the reason why I am asking the group in I am running into problems where the systems are not in sync Help !!! I see the option in the compile but I have found no instructions on how to implement this. anyway thanks in advance of all of the responses. (Including the flames)
Re: [vchkpw] vpopmail clustering examples
Scott do you also mount the queue dir's from the netapp ??? - Original Message - From: Scott Helms [EMAIL PROTECTED] To: Duane Wylie [EMAIL PROTECTED]; [EMAIL PROTECTED] Sent: Monday, December 30, 2002 11:16 AM Subject: Re: [vchkpw] vpopmail clustering examples Duane, We use Alteons to do the load balancing and a pair of NetApp F810c's for the HA NFS system. I won't include any details since its easy enough to get the data from the guys at Netapp. We run 7 qmail/vpopmail servers with 3 mysql servers (one master and 2 slaves that are read only). Scott - Original Message - From: Duane Wylie [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Monday, December 30, 2002 1:41 PM Subject: RE: [vchkpw] vpopmail clustering examples Sorry 'bout sending that last message as 'Super-User'... We're using F5's load balancer and it's been working great for us. It has similar features as the Foundry switch you mentioned (and the service monitoring is great!). The main worry I have at this point is the NFS server. Even though the file system in question is RAID 5, and is in a separate disk enclosure, I don't like having that one NFS server as a single point of failure. Is anyone using some sort of HA storage solution? If so, care to share details? Thanks, Duane Wylie -Original Message- From: Andre Fortin [mailto:[EMAIL PROTECTED]] Sent: Monday, December 30, 2002 11:53 AM To: [EMAIL PROTECTED] Subject: RE: [vchkpw] vpopmail clustering examples We have a very similar set up. We have a third machine as the MySQL master which doesnt directly interact as a mail server, but it makes the MySQL database triple-redundant without sacrificing performance. For load balancing/redundancy, we are using Foundry (http://www.foundrynetworks.com/) switches with the SLB (Server Load Balancing) code. Very powerful; it not only detects if the server is running, or listening to port 25/110, but it actually understands SMTP and POP3 and will make sure the SMTP and POP3 servers are responding properly as part of its 'heartbeat' tests.. So, for example, if you had a machine that had a problem and would still listen to port 25 but couldnt actually answer with a '220', it would be treated as 'offline' instead of opening dead connections for clients.. It also allows you to load balance between X number of servers rather than just failing over in 'worst case scenario' situations.. Andre
[vchkpw] vpopmail clustering examples
is there anyone out there in vpopmail land that knows where there is any information on clustering or loadbalancing vpopmail. what I mean by this is having multiple copies of vpopmail running on more than one server. the reason why I am asking the group in I am running into problems where the systems are not in sync Help !!! I see the option in the compile but I have found no instructions on how to implement this. anyway thanks in advance of all of the responses. (Including the flames)
Re: [vchkpw] vpopmail/qmail migration
make sure that the permission (uid and gid are the same on the new server. also the qmail control files need to be copied over also. and the db needs to match everything else. so to sum it all up.. qmail, /var/vpopmail and the db all need to match. I have done this many times and it is a very tricky operation. John - Original Message - From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Sent: Monday, November 18, 2002 1:01 PM Subject: [vchkpw] vpopmail/qmail migration I have an existing vpopmail/qmail server hosting several domains. I've put together a new server on the same subnet to replace the old one. vpopmail is configured and functioning properly on the new server. My plan is to simply copy the /home/vpopmail/* directory to the new server, and move the IP address from new to old. My question is: Are there any important files withing /var/qmail or elsewhere that also need to be moved at the time of migration? Thank you. -- -- Zak L Brown, R.H.C.E. Systems Administrator Webnetone
