On Wed, Jul 16, 2008, fabian dacunha wrote: > >Dear ALL > >I have the following setup running good for quite sometime and i wd really >apprecite if someone wd help or give some suggestions > >centos 5.1 >sendmail >dns server > >now recently our mail usage has increased considerably and moreover Mails >have become a utmost top priority > >i have 2 options now > >1) have a backup server with lower higher MX > >i tested this setup n had some queries earlier n thanks to guys like scott >for some prfect advise i did manage to check it out n it works beautiful > >2) have another server with same value of MX so it cd load balance and >also doc says if one server is down or unavaliable the oher server would >receive mail > >now my query is ... if i now configure a second mail server with same MX >priority . Having multiple servers with the same MX priority works fine (I prefer to think of this as distance as the lower ones have higher priority). There's no good reason to have multiple distances other than the shortest for final delivery and one or more with higher in case the primary is not available for some reason. >a) do i have to create all the existing user accounts on my existing email >server to this new server >cause i already hav about 300+ email users already No, the secondary MX server(s) don't need any user accounts. Using postfix, we do generate a virtual file for each secondary MX server containing all the valid addresses for the domain(s) served by the primary server, allowing the MX servers to reject invalid accounts without having real user accounts. There are some good arguments for having a single MX server rather than multiple MX servers as it prevents spammers from attempting to deliver mail through the higher distance MX servers which may well not have the same anti-spam rules. At one of our regional ISP customers with about 10,000 e- mail accounts, we use a single MX server to accept incoming messages, This server runs postfix, amavisd-new, and clamav to pre-screen incoming messages for worms (Windows is the Virus) and phishing messages, then it forwards clean messages to a cluster of systems that do spamassassin checking and message delivery to the user's Maildir message stores which are NFS mounted on a central server. The MX server in this case rejects about 2,000,000 messages a day using a variety of IP filters, and delivers about 250,000 messages a day. It has a load average less than 1.00 except during the daily maintenance and security audits. It actually is the primary MX server for two distinct groups of domains, each with a separate user base. Each machine that is home to the user's home directories updates its own section of the postfix virtual table, using rsync to update the MX server whenever anything changes with the users. The MX server uses the postfix transport file to direct mail to the appropriate cluster servers to deliver mail. Bill -- INTERNET: bill at celestial.com Bill Campbell; Celestial Software LLC URL: http://www.celestial.com/ PO Box 820; 6641 E. Mercer Way Voice: (206) 236-1676 Mercer Island, WA 98040-0820 Fax: (206) 232-9186 People from East Germany have found the West so confusing. It's so much easier when you have only one party. -- Linus Torvalde, Linux Expo Canada when asked about confusion over many Linux distributions.