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Backup MX - It's The Least You Can Do

When I ask organizations to list their mission critical applications, e-mail is always on the list. While organizations are investing in all sorts of high-availability solutions for their e-mail servers, I'm amazed at how often they skip the inexpensive steps that will insure that legit e-mail doesn't get bounced if the e-mail server is down. When your mail server, or Internet connection, is down, a backup MX, or mail exchange, server will accept mail for your domain and forward it automatically
When I ask organizations to list their mission critical applications, e-mail is always on the list. While organizations are investing in all sorts of high-availability solutions for their e-mail servers, I'm amazed at how often they skip the inexpensive steps that will insure that legit e-mail doesn't get bounced if the e-mail server is down. When your mail server, or Internet connection, is down, a backup MX, or mail exchange, server will accept mail for your domain and forward it automatically to your mail server when it comes back on line.All you have to do is sign up with a provider and add their mail servers to the MX records that identify the mail servers for your domain(s). By setting the backup servers to a higher preference, legit e-mail servers will deliver mail to the backup MX server to queue for you only if your server(s) are unavailable.

Some e-mail servers, usually spam generators, choose the highest preference (lowest priority) server from an array of MX records, assuming that the lowest priority server has lower shields than the primary servers. Since backup MX providers typically try to deliver mail they've queued up to your server every 15 minutes to an hour, mail from these sources may be slightly delayed.

Most e-mail servers retry over a longer cycle. I've seen delays of up to 4 hours if the message wasn't delivered in the first 30 minutes. Backup MX should speed recovery after an outage. Some providers also have a mechanism like sending a ETRN command to request delivery so you can clear the queue.

So, you're asking, where do I sign up? Try:

www.mxsave.com

www.dnsmadeasy.com

www.easydns.com

or the always useful Google.

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