can't the secondary mx be configured to simply deliver the mail as the
primary would? in which case there would be no delay...
On Thu, 30 Mar 2000, Jeremy Hansen wrote:
> Basically I want some pros and cons on using MX's for load balancing mail
> hosts. I know this doesn't seem to be LVS related, but it is because I'm
> currently using LVS for this operation and it's working perfectly, but
> someone I met with yesterday is using another method, MX's with the same
> priority to basically do the same thing, when he mentioned this it didn't
> sit well with me for some reason but I couldn't put my finger on why and
> mainly I think it has to do with fail over incase one of these MX hosts
> are down.
> In our particular situation our goal is high volume mail. The goal is to
> get as much mail out as fast as possible.
> In a MX load balancing situation, it seems to me that although it may
> work, it's not as efficient in the goal incase a machine is failed.
> This is my understand on how it would work using MX's. If whatever dns
> determines to be the target host, if the host is failed, then the mail get
> deferred to a secondary MX host and is held until the original targeted MX
> host is back up then the secondary pushes that mail back to the original
> target. So mail is deferred and delayed. Will this be the case even if
> the MX priorities are the same? I'm assuming once an MTA determines which
> host it decided to go to, this address doesn't change even with the same
> priority levels.
> In an LVS situation (assuming you have a good setup and monitoring to take
> downed hosts out of the LVS pool) this wouldn't happen. You hit the
> virtual address and it goes to a valid "up" machine and there is no delay.
> So LVS still seems better, but I wanted to ask others incase my
> assumptions are wrong.