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Community Member

Alt-Mailhost / SMTP Routes Question...

Hi All,

I have a query on SMTP routing when using the Alt-Mailhost command in a Message Filter...

Our configuration in overview is two Ironport devices (C650's at AsyncOS 6.4) at separate sites, configured as a cluster (all config is common across sites). At each site, there also exists a 3rd party mail host.

So, I have a message filter which selects messages based on some criteria and I also know which Ironport received it. When I have a match, I want to route this message to the 3rd party mail host on the _local_ site......but if that mail host is down, I want to route it to the 3rd party mail host on the other site. Simple as that!

At the moment, my Alt-Mailhost command looks like this;

<message has been selected> {

<if "Site A" Ironport used> {





} my SMTP Routes I'd _like_ to have this;     <3rd-Party-Box-at-Site-A>, <3rd-Party-Box-at-Site-B>     <3rd-Party-Box-at-Site-B>, <3rd-Party-Box-at-Site-A>

...but this doesn't work because multiple hosts in an SMTP route are tried in numerical / alphabetical matter what order you put them into the SMTP Route definition (is this a bug?) in reality, they both have to look like this;     <3rd-Party-Box-at-Site-A>, <3rd-Party-Box-at-Site-B>     <3rd-Party-Box-at-Site-A>, <3rd-Party-Box-at-Site-B>

..which is no use.

My only other idea is that I could just have this in the SMTP Routes for those domains;     USEDNS     USEDNS

...and configure my DNS with the above domains, such that there really _is_ a difference in the order of the MX for those domains.

So my question is, how can I do this without using 'USEDNS' and the associated DNS config...i.e. just via the Ironport devices?

Hope the collective can help!

Cheers, Chris.

Everyone's tags (2)
Community Member

Re: Alt-Mailhost / SMTP Routes Question...

Check out the latest release notes...

Enhanced: Prioritized SMTP Routes
AsyncOS 7.0 allows you to prioritize the destination hosts for your SMTP routes. AsyncOS will attempt to deliver the message to a destination host in order based on priority. Destinations with identical priority will be used in a “round-robin” fashion.

Community Member

Re: Alt-Mailhost / SMTP Routes Question...

Aha!.. thanks Chris I will go check that out....

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