With Hurricane Irene bearing down upon the east coast of the United States, I thought I’d take a moment to explain how our Store and Forward services work. If your mail server is located in a facility that is in the path of the hurricane, you might be concerned about your mail server losing power or network connectivity and what will happen to your mail should that occur.

userprotect

If you use our userprotect service, we will continue to accept mail for your users if your mail server goes down. We will hold any messages we receive for 5 days or until your mail server comes back online.

cloudprotect (and DomainProtect / ServerProtect)

If you use our cloudprotect service (or our old DomainProtect and ServerProtect accounts), our Store and Forward services work a little differently because the user list for your domain is maintained dynamically. When we receive a message for a user on your domain, we contact your mail server to validate that the user is an accepted user.  If your server is available and responds that it accepts mail for that user, we put that email address in a “positive” cache for 24 hours. If your server responds that it does not accept mail for that address, we put it in a “negative” cache for 30 minutes.

When your mail server goes down and we receive an email for a user on your domain, we first check the cache to see if we have an active record for that user.  If we do and it’s a “positive” record, we will queue the mail on our gateway for 5 days or until your server comes back online.  If we do and it’s a “negative” record, we reject the message.  If we don’t have an active cache record for the address, we will respond to the sending server with a temporary failure message and the message will be queued on the sending server.  It will be queued there according to the sending server’s policies … typically it will retry to send it periodically for up to 5 days.  When it
retries, if we still can’t contact your server we’ll issue a temporary failure again.  If we CAN contact your server again, we’ll follow our standard mail acceptance procedures as outlined in the previous paragraph.

Store and Forward services are included on all Purity Networks Email Protection Services accounts at no charge.

Please contact support@purity.net if you have any questions.

This entry was posted on Friday, August 26th, 2011 at 2:36 pm and is filed under General. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.