The Xeriom Mail Service
We run a simple MX platform which can be used to increase the reliability of email delivery for all domains which use your VM as the primary MX.
Simply add our MX servers to the zone for the domain in such a way that they'll be delivered to only if your primary MX (ie your VM) is down.
Say the primary MX for xeriom.net mail was normally mail.xeriom.net, and that mail.xeriom.net lived on a VM inside the Xeriom network, then we'd add the Xeriom MX servers at higher priority.
xeriom.net. IN MX 10 mail.xeriom.net. xeriom.net. IN MX 20 mx1.xeriom.net. xeriom.net. IN MX 20 mx2.xeriom.net. xeriom.net. IN MX 20 mx3.xeriom.net.
Note that your primary MX should be responsible for spam and virus scanning - our MX service simply asks that email sent through it comply to the appropriate RFCs and have a final MX destination somewhere within our network.
If you're interested in how our MX service is setup, check out my blog post on the subject at