On Thu, 6 Feb 2003 06:28, Lauchlin Wilkinson wrote: > does anyone have any good links/info on how to set up a > loadsharing/redunant mail servers (pop, imap, smtp). At the moment I > have 1 server doing all three jobs but we are soon going to grow out of > this arrangment andI have not had any experience with setting up such > systems.
Load sharing and redundancy are two totally different issues. If you want redundancy then the best thing to do is get a pair of NFS attached storage devices running in an an active/standby configuration and have the SMTP/POP/IMAP servers mounting the storage by NFS and using Maildir storage. This will cost huge amounts of money. For load sharing I've got Dell 2650 servers with 2*1.8GHz Xeon CPUs, 4G of RAM, and 5*72G U160 hard drives (4 in a RAID-5 and a hot-spare) that each run 200,000 email accounts with Qmail for delivery and Courier IMAP and POP servers. At the front end I have Perdition for directing the POP and IMAP to the right server based on LDAP data (NB the current version in Unstable still doesn't work properly for this - the next version should do it). Also I have front end Qmail servers which direct the mail to the correct back-end server based on LDAP. For typical ISP use you should be able to handle at least 100,000 users for SMTP, POP, and IMAP on a single box without any significant problems (and it'll be much easier than installing Perdition etc). I could setup a single machine to handle 1,000,000 accounts if required, it would be an expensive machine, but setting up a number of smaller machines with Perdition etc is also expensive and has management costs too. -- http://www.coker.com.au/selinux/ My NSA Security Enhanced Linux packages http://www.coker.com.au/bonnie++/ Bonnie++ hard drive benchmark http://www.coker.com.au/postal/ Postal SMTP/POP benchmark http://www.coker.com.au/~russell/ My home page -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
