Also... Round-robin DNS is more of a quick-n-dirty load distributor, as DNS records can be cached several places along the way.
http://www-1.ibm.com/servers/esdd/articles/sendmail/ For high-volume traffic, or limited resources, actual load-balancing per session (compared to DNS query/cache) will improve performance. In our case we have a load-balancing appliance with lower MX, then higher MX for the actual individual machines should the appliance fail. If a company can't afford a CISCO or BigIP device, two IMGate servers with LVS would be an excellent alternative and method of combining both load-balancing and gateway features. -ives ----- Original Message ----- From: "Rick Davidson" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, June 19, 2003 6:02 PM Subject: SPAM: The Below EMail May Be SPAM ----- Re: [IMail Forum] More on Peering > They can be set to the same preference but not necessarily depending on what > you want to do. You could load balance by setting the same MX preference. > > You can protect some of your peers by only allowing connections from the > main peers and not having them included in the MX records > > Lets say you have 6 peers but only a two of them have fat pipes, you include > those two in the MX records and lets say the other 4 hosts are on DSL > connections. You could run virus and spam filtering on the MX peers and only > allow SMTP connections from the peers to the peers on the DSL connections. > This is great for companies with branch offices and alot of users. > > There is definately a good amount of config flexibility with the peering > > Rick Davidson > Buckeye Internet Inc > www.buckeyeweb.com > 440-953-1900 ext: 222 > > ----- Original Message ----- > From: "Len Conrad" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Thursday, June 19, 2003 5:14 PM > Subject: Re: [IMail Forum] More on Peering > > > > > > >You will need an MX record for each peer that you want to act as a > > >backup. > > > > > >for example if you have 3 peers > > >mail1.domain.com > > >mail2.domain.com > > >mail3.domain.com > > > > > >You point the primary MX record point to mail1.domain.com > > >the secondary MX to mail2.domain.com > > >and if you want add a tertiary MX record pointing at mail3.domain.com > > > > Shouldn't all the (peered) MXs be the same preference value? If you have > > MX 10, 20, 30, then 10 will receive all mail and have re-deliver to 20 and > > 30, while 20 or 30 receive no MX traffic, only the re-deliveries from 10. > > > > But if all are MX 10, then if one is down, the others will be tried, > > maintaining load sharing and MX failover. > > > > Len > > > > _____________________________________________________________________ > > http://MenAndMice.com/DNS-training: New York; Seattle; Chicago > > IMGate.MEIway.com: anti-spam gateway, effective on 1000's of sites, free > > > > > > To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html > > List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ > > Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ > > > > > > > To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html > List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ > Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/ > To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
