# postfix: weird IPv6 bounce



## cbrace (Aug 17, 2010)

Hi all,

Mail to the host vevida.com, which hosts a couple of domain names of people with whom I exchange mail, keeps bouncing because the mailserver addresss resovlves to an IPv6 address.

From the mailq:


```
$ mailq
-Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient-------
62E955C2A      3509 Tue Aug 17 11:44:13  cb@lim.nl
              (connect to mx4.vevida.com[2a00:f60::1:36]:25: No route to host)
                                         gd@xxx.nl

46B685C20      3556 Mon Aug 16 12:36:01  cb@lim.nl
              (connect to mx2.vevida.com[2a00:f60::1:48]:25: No route to host)
                                         gd@xxx.nl

DAB745C28      3513 Tue Aug 17 11:43:53  cb@lim.nl
              (connect to mx3.vevida.com[2a00:f60::1:34]:25: No route to host)
                                         gd@xxx.nl
```
If I look at the domain record, I see both ipv4 as well as v6 addresses for the resp. mailservers:

```
$ dig vevida.com MX

; <<>> DiG 9.6.1-P3 <<>> vevida.com MX
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 48226
;; flags: qr rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 0, ADDITIONAL: 15

;; QUESTION SECTION:
;vevida.com.			IN	MX

;; ANSWER SECTION:
vevida.com.		900	IN	MX	10 mx3.vevida.com.
vevida.com.		900	IN	MX	10 mx2.vevida.com.
vevida.com.		900	IN	MX	10 mx1.vevida.com.
vevida.com.		900	IN	MX	10 mx4.vevida.com.
vevida.com.		900	IN	MX	20 backup-mx.vevida.com.

;; ADDITIONAL SECTION:
mx2.vevida.com.		166	IN	A	77.94.249.35
mx4.vevida.com.		166	IN	AAAA	2a00:f60::1:37
mx3.vevida.com.		166	IN	AAAA	2a00:f60::1:29
mx3.vevida.com.		166	IN	AAAA	2a00:f60::1:31
mx3.vevida.com.		166	IN	AAAA	2a00:f60::1:37
mx4.vevida.com.		166	IN	AAAA	2a00:f60::1:44
mx3.vevida.com.		166	IN	A	77.94.249.48
mx1.vevida.com.		166	IN	AAAA	2a00:f60::1:36
mx1.vevida.com.		900	IN	A	77.94.249.33
mx3.vevida.com.		166	IN	AAAA	2a00:f60::1:38
mx1.vevida.com.		900	IN	A	77.94.249.44
mx1.vevida.com.		166	IN	AAAA	2a00:f60::1:30
mx2.vevida.com.		166	IN	A	77.94.249.31
mx3.vevida.com.		166	IN	AAAA	2a00:f60::1:36
mx1.vevida.com.		166	IN	AAAA	2a00:f60::1:44
```
Any ideas why postfix is grabbing the ipv6? How can I fix this?

Thanks,
-Colin


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## DutchDaemon (Aug 17, 2010)

I believe you need to set inet_protocols in main.cf to ipv4 (it may be 'all' now).


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## knarf (Aug 17, 2010)

cbrace said:
			
		

> Any ideas why postfix is grabbing the ipv6? How can I fix this?



You've enabled ipv6 on your host, but your v6 connectivity is broken (no route to host). You should fix that instead of trying to disable v6 in postfix. You'll notice these problems with all types of software trying to connect to v6 enabled sites (try ftp ftp.freebsd.org for example). Connecting to AAAA record is preferred over the A record.


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