Why is IP4 traffic being turned into IPv6?
My Linux Linode only has an IPv4 address. Every day at UTC a cron job uses sendmail/postfix to send me an email.
This has been working for many weeks. Suddenly it stops working a few days ago. The reason is apparently the search for an MX record is being converted to an IPv6 address and it's not even the right host.
The mail server does not have an IPv6 address.
I need to somehow force everything to use IPV4 address space like it was for several weeks.
This snippet should explain a little more:
root@localhost:~# /usr/bin/top -n 1 -b|/usr/bin/mail -s "Linode larry@larkat.com" larry@larkat.com
root@localhost:~# mailq
-Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient-------
4F390F25A4 7821 Mon Jun 13 14:55:04 root@localhost
(Host or domain name not found. Name service error for name=home.larkat.com type=AAAA: Host found but no data record of requested type)
larry@larkat.com
1 Reply
My Linux Linode only has an IPv4 address.
No, it has both an IPv4 address and an IPv6 address. Look at your Linode in the Cloud Manager…you will see both addresses.
The mail server does not have an IPv6 address.
If the Linode has an IPv6 address, the mail server that the Linode hosts has an IPv6 address.
The reason is apparently the search for an MX record is being converted to an IPv6 address and it's not even the right host.
Sounds like a hack to me… I'd scan your Linode for exploits/viruses using whatever tool you like in recovery mode.
-- sw
PS. larkat.com (domain mentioned in your postfix report) is a dummy website…or under development. Company name is fake (Dynamic Synergistics or some other Stanford B-School tripe) and virtually every piece of text is lorem ipsum… Good luck… You may be looking at rebuilding your Linode if you can’t get rid of whatever pestilence it’s contracted.