[SOLVED] dhcpcd IPv6 prefix delegation on router

train_wreck · 2014-04-21 02:30:12

have a working Arch router that i am enabling IPv6 on. i'm following this article https://wiki.archlinux.org/index.php/router#IPv6 specifically in the section "Acquiring WAN IPv6 via DHCPv6-PD". I'm following the instructions for additions to dhcpcd.conf, but am getting the following error (""internal" is the name of the internal interface on the router; "external" is the external one"):

dhcpcd[370]: external: confirming Prefix Delegation
dhcpcd[370]: external: REPLY6 received from fe80::201:5cff:fe3f:d241
dhcpcd[370]: internal: interface does not exist for delegation

The internal interface most definitely "exists"; it is up and has an IPv4 address assigned to it. I have tried manually assigning it a link-local address as well as a ULA /64 address, with no change in result. Googling this error brings up next to no information; indeed, put it in quotes and literally all you get are 2 results for the source code of dhcpcd. Any ideas? My ISP is Comcast, which definitely has enabled IPv6 /64 prefixes for its customers, at least in my area, and I am able to pull a global /64 address on the external interface by itself.

Last edited by train_wreck (2014-04-21 09:19:41)

train_wreck · 2014-04-21 03:18:41

update, tried dibbler, configured it as the article says. it gives me the following error:

dibbler-client[477]: 20:57 Client Warning  Suitable interfaces not found. Delegated prefix not split.

once again, googling this result leads mostly nowhere. dibbler definitely is aware of the internal interface, stating "Detected iface internal/2, MAC=xx:xx:xx:xx:xx:xx"

Last edited by train_wreck (2014-04-21 03:20:01)

train_wreck · 2014-04-21 03:44:16

and wide-dhcpv6 doesn't even start, giving the following error:

client6_init: failed initialize control message authentication
client6_init: skip opening control port
dhcp6c_ctl_authinit: failed to open /etc/wide-dhcpv6/dhcp6cctlkey: No such file or directory
client6_recvadvert: XID mismatch
add_ifprefix: invalid prefix length 64 + 8 + 64

kinda lost at this point

Last edited by train_wreck (2014-04-21 03:51:50)

train_wreck · 2014-04-21 09:15:50

solved it, wide-dhcpv6 expects a directory /var/lib/dhcpv6 to exist, but the AUR package doesn't create it during install, so it errors out with this. Also, the wiki article states that dhcp6c.conf should have a line containing "sla-len 8;". For a /64 prefix that my ISP provides, this value is incorrect, and should be 0. Changed these things, and everything's fine now.

Last edited by train_wreck (2014-04-21 09:18:30)

Foucault · 2014-04-21 13:03:31

train_wreck wrote:

solved it, wide-dhcpv6 expects a directory /var/lib/dhcpv6 to exist, but the AUR package doesn't create it during install, so it errors out with this. Also, the wiki article states that dhcp6c.conf should have a line containing "sla-len 8;". For a /64 prefix that my ISP provides, this value is incorrect, and should be 0. Changed these things, and everything's fine now.

Indeed the sla-len 8 was for a /56 prefix (so 56+8+64=128). I've edited the wiki and I've also updated the wide-dhcpv6 package.

You can also try dhcpcd for IPv6-PD. It works more smoothly and is easier to configure.

train_wreck · 2014-04-21 17:52:16

thanks a lot.

though on the dhcpcd, that was my original attempt, and was the first post of the thread i tried it with this config added:

duid
noipv6rs
interface external
ia_pd 1 internal

and got the error that I posted originallly.

Foucault · 2014-04-21 20:23:06

Damn, that was some sloppy reading. If you are using ppp make sure that you put that (ppp0, ppp1, whatever) on "interface". You could also want to try tuning the various options for ia_pd (search the dhcpcd.conf manpage for ia_pd). You might need something like "internal/0". That being said, that's a weird error and the lack of search results makes it even more frustrating. If you want to pursue it further you could ask at the mailing list of dhcpcd.

train_wreck · 2014-04-21 21:32:51

nope, no ppp, "external: is just an ethernet adapter to a cable modem. and i'm fine using wide-dhcpv6, tbh. i tend to prefer dhclient over dhcpcd, anyway

rsmarples · 2014-04-28 23:29:33

train_wreck wrote:

have a working Arch router that i am enabling IPv6 on. i'm following this article https://wiki.archlinux.org/index.php/router#IPv6 specifically in the section "Acquiring WAN IPv6 via DHCPv6-PD". I'm following the instructions for additions to dhcpcd.conf, but am getting the following error (""internal" is the name of the internal interface on the router; "external" is the external one"):
dhcpcd[370]: external: confirming Prefix Delegation
dhcpcd[370]: external: REPLY6 received from fe80::201:5cff:fe3f:d241
dhcpcd[370]: internal: interface does not exist for delegation
The internal interface most definitely "exists"; it is up and has an IPv4 address assigned to it. I have tried manually assigning it a link-local address as well as a ULA /64 address, with no change in result. Googling this error brings up next to no information; indeed, put it in quotes and literally all you get are 2 results for the source code of dhcpcd. Any ideas? My ISP is Comcast, which definitely has enabled IPv6 /64 prefixes for its customers, at least in my area, and I am able to pull a global /64 address on the external interface by itself.

Basically it means that dhcpcd was limited to running on the external interface and thus has no notion of the internal interface.
This has been resolved here, amongst other things:
http://roy.marples.name/projects/dhcpcd … 8fdf?sbs=0

rsmarples · 2014-04-28 23:31:40

train_wreck wrote:

i tend to prefer dhclient over dhcpcd, anyway

Why?

train_wreck · 2014-04-29 04:14:04

because i find it tends to work better with my ISP; dhcpcd has a tendency to randomly time out where dhclient never does

rsmarples · 2014-04-29 06:36:55

train_wreck wrote:

because i find it tends to work better with my ISP; dhcpcd has a tendency to randomly time out where dhclient never does

Could you provide a log with debug enabled in dhcpcd.conf of dhcpcd timing out please so I can have a shot at fixing it for you?

train_wreck · 2014-04-29 13:33:34

if i have time, yeah ill load it back on the router & post back. itll prolly be a new topic

Arch Linux

#1 2014-04-21 02:30:12

[SOLVED] dhcpcd IPv6 prefix delegation on router

#2 2014-04-21 03:18:41

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#3 2014-04-21 03:44:16

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#4 2014-04-21 09:15:50

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#5 2014-04-21 13:03:31

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#6 2014-04-21 17:52:16

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#7 2014-04-21 20:23:06

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#8 2014-04-21 21:32:51

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#9 2014-04-28 23:29:33

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#10 2014-04-28 23:31:40

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#11 2014-04-29 04:14:04

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#12 2014-04-29 06:36:55

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

#13 2014-04-29 13:33:34

Re: [SOLVED] dhcpcd IPv6 prefix delegation on router

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