IPv6-only Installation

Issues related to configuring your network
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jeffl
Posts: 3
Joined: 2011/07/12 14:40:45

IPv6-only Installation

Post by jeffl » 2011/07/12 14:47:46

I'm unable to get Centos 5 or 6 to install over IPv6. I'm using mirrors.kernel.org, which has a AAAA record. Here is the behavior that I see.

Centos 5 - Performs lookup for A record. Receives A record responses (IPv6 connectivity works). The installer does not query for an AAAA record.

Centos 6 - Performs neither A or AAAA record query.

I'm curious to hear if anyone has been successful installing Centos without IPv4 being activated.

Jeff L.

godspeed
Posts: 8
Joined: 2011/06/28 14:44:31

IPv6-only Installation

Post by godspeed » 2011/07/19 16:46:26

mirrors.kernel.org is not ipv6 only, it's dual-stack dns server.
so if you want install over ipv6, the domain must have ipv6 only dns server.

jeffl
Posts: 3
Joined: 2011/07/12 14:40:45

Re: IPv6-only Installation

Post by jeffl » 2011/07/19 21:23:32

godspeed,

A resolver on an IPv6-only end-system should not query for A (IPv4) records. These are useless to the system. mirrors.kernel.org has an AAAA (IPv6) record. The installer needs to send a query for the AAAA record. For some reason, it is not doing so. I could hazard a guess that the developers did not test an installation with the IPv4 stack disabled. I'd like to hear from them before publishing my findings.

Jeff L.

godspeed
Posts: 8
Joined: 2011/06/28 14:44:31

Re: IPv6-only Installation

Post by godspeed » 2011/07/20 08:01:03

yes. i know installer not send query for AAAA record.
but, i test ipv6 only dns server at 2009, if the remote dns server is dual-stack and the client(local ipv6 dns server) is ipv6 only, you can't get any ipv6 record.

[root@mailtest source]# dig mirrors.kernel.org any

; > DiG 9.3.6-P1-RedHat-9.3.6-4.P1.el5 > mirrors.kernel.org any
;; global options: printcmd
;; Got answer:
;; ->>HEADER> DiG 9.3.6-P1-RedHat-9.3.6-4.P1.el5 > www.tyut6.edu.cn
;; global options: printcmd
;; Got answer:
;; ->>HEADER> DiG 9.3.6-P1-RedHat-9.3.6-4.P1.el5 > www.tyut6.edu.cn any
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 50182
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 0

;; QUESTION SECTION:
;www.tyut6.edu.cn. IN ANY

;; ANSWER SECTION:
www.tyut6.edu.cn. 31443 IN AAAA 2001:250:c01::11:246

;; AUTHORITY SECTION:
tyut6.edu.cn. 31443 IN NS dns1.tyut6.edu.cn.
tyut6.edu.cn. 31443 IN NS dns2.tyut6.edu.cn.

;; Query time: 3 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Wed Jul 20 15:52:06 2011
;; MSG SIZE rcvd: 100

godspeed
Posts: 8
Joined: 2011/06/28 14:44:31

Re: IPv6-only Installation

Post by godspeed » 2011/07/20 16:20:18

[quote]but, i test ipv6 only dns server at 2009, if the remote dns server is dual-stack and the client(local ipv6 dns server) is ipv6 only, you can't get any ipv6 record.[/quote]

local domain(ipv6 only) has dns server and cliet, client nameserver is local dns server.
if the remote dns server is dual-stack, you can't get any 4A record.

jeffl
Posts: 3
Joined: 2011/07/12 14:40:45

Re: IPv6-only Installation

Post by jeffl » 2011/07/20 21:34:18

godspeed,

I'm having difficulty parsing your statements. It sounds as though you are suggesting that dual-stack DNS servers won't return AAAA records over IPv6 transport. If this were true, there would be a lot of IPv6-only end stations that would be useless right now.

Jeff L.

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