>Number: 152458
>Category: misc
>Synopsis: rtadvd neetds to allow RA without a prefix info option
>Confidential: no
>Severity: non-critical
>Priority: low
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Sun Nov 21 19:40:11 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator: Steinar Haug
>Release: 7.3-STABLE
>Organization:
Nethelp Consulting
>Environment:
FreeBSD dhcp1.noc.ventelo.net 7.3-STABLE FreeBSD 7.3-STABLE #8: Sun Nov 14
21:36:26 CET 2010
sth...@dhcp1.noc.ventelo.net:/usr/src/sys/i386/compile/DHCP1 i386
>Description:
In IPv6 it should be possible to generate a Router Advertisement which
contains no prefix info option (the idea being that I want a host on the
LAN to populate its default router list but nothing else). However, I
cannot seem to get rtadvd to do this.
My Juniper routers can do this without any problem.
If I start rtadvd with no /etc/rtadvd.conf file, it sends RAs with a
prefix info option corresponding to the IPv6 address of the interface.
In the /etc/rtadvd.conf I can explicitly specify prefixes ("addr"),
but I can't find any way to specify that no prefix info option should
be sent.
If I start rtadvd with the -s option, it still sends RAs with a prefix
info option corresponding to the IPv6 address of the interface.
If I start rtadvd with a config file which specifies a prefix using
the "addr" option, I can get rtadvd to send RAs without the "auto"
flag - thus the prefix won't be used for SLAAC. E.g.:
em1:raflags="m":pinfoflags="l":addr="2001:8c0:8500:3::"
gives me a RA like the following (tcpdump output):
20:26:15.469184 IP6 (hlim 255, next-header ICMPv6 (58) payload length: 56)
fe80::214:22ff:fe1a:8439 > ff02::1: [icmp6 sum ok] ICMP6, router advertisement,
length 56
hop limit 64, Flags [managed], pref medium, router lifetime 1800s,
reachable time 0s, retrans time 0s
source link-address option (1), length 8 (1): 00:14:22:1a:84:39
prefix info option (3), length 32 (4): 2001:8c0:8500:3::/64, Flags
[onlink], valid time 2592000s, pref. time 604800s
But this is not quite the same as not announcing a prefix.
It's possible we simply have some missing functionality here.
>How-To-Repeat:
Start rtadvd. Observe using tcpdump or similar that a prefix info option is
always included in the RAs transmitted on the interface.
>Fix:
>Release-Note:
>Audit-Trail:
>Unformatted:
_______________________________________________
freebsd-bugs@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-bugs
To unsubscribe, send any mail to "freebsd-bugs-unsubscr...@freebsd.org"
