IPv6 email autoreply facility

In the past two days, I was busy setting up an autoreply facility for IPv6 email. My experience is that if system administrators set up their IPv6 SMTP servers, it is difficult for them to find IPv6-enabled mail servers for mail transaction tests. Even if they found some, how can they make request to ask some body to help the test. What I try to do is to set up an IPv6 only SMTP server, dedicate an email account with autoreply so that other system administrators can perform IPv6 mail transaction without bothering to call me.

Luckily, I got the domain “v6-mail.com”. Logically, the email account for autoreply function is “autoreply@v6-mail.com”. I continued to configure my DNS to handle MX and AAAA records. Next, I installed Postfix on a dual-stack Linux server with 6to4 tunnelling and I forced Postfix to listen to IPv6 address only. Then came the most difficult task. How to enable autoreply function on the user “autoreply”. I used .forward and vacation but the problem is vacation only reply to sender once within a day and any other subsequent email received from the sender will not be replied. I recalled that flushing vacation.db will clear all previous locked records so I added an cron job to do “/usr/bin/vacation –I” on a per minute basis. This solved all problem plus it added anti-spam feature. If the sender sends more than one request to “autoreply@v6-mail.com” for testing, only one autoreply message will be delivered within a minute.

All these bundled together work up to my expectation. I am very glad that I have developed something helpful to the IPv6 community.