Re: FreeBSD does not reply to IPv6 Neighbor Solicitations
> Victor Sudakov wrote: > > Dear Colleagues, > > > > Why could it be that a FreeBSD 12.2 host does not reply to ICMPv6 > > Neighbor Solicitations from the router? > > Any ideas please? Thank you for pointing this out. I do have an similar effect, after upgrading, and you point me to a good direction. I'll investigate and report back. Lutz Donnerhacke ___ freebsd-net@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
Re: FreeBSD does not reply to IPv6 Neighbor Solicitations
On 4 Jan 2021, at 14:17, Lutz Donnerhacke wrote: Victor Sudakov wrote: Dear Colleagues, Why could it be that a FreeBSD 12.2 host does not reply to ICMPv6 Neighbor Solicitations from the router? Any ideas please? Thank you for pointing this out. I do have an similar effect, after upgrading, and you point me to a good direction. I'll investigate and report back. I’d start by checking netstat -s -p icmp6 and netstat -s -p ip6 for any suspicious counter updates. Another thing to do might be to turn on nd6 log/debugging by sysctl (sysctl net.inet6.icmp6.nd6_debug=0xff should do it) and keep an eye on the kernel messages. /bz ___ freebsd-net@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
AW: FreeBSD does not reply to IPv6 Neighbor Solicitations
> I’d start by checking netstat -s -p icmp6 and netstat -s -p ip6 for > any suspicious counter updates. Great idea. It points me tot he most stupid error I could make. Instead of ifconfig_lagg140_aliases="inet6 2a01:75c0:1000:140::/64 anycast" I wrote ifconfig_vlan140_aliases="inet6 2a01:75c0:1000:140::/64 anycast" so the IPv6 address was not set after reboot. This fails to get noticed, due the long lifetime of the announced prefix. (the error has been visible since a few days only, I had no time to investigate) So I can confess, plain 12.2-STABLE is no broken. ___ freebsd-net@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
Re: FreeBSD does not reply to IPv6 Neighbor Solicitations
Paul Mather wrote: > Why could it be that a FreeBSD 12.2 host does not reply to ICMPv6 > Neighbor Solicitations from the router? [dd] > > > > $ ifconfig re1 > > re1: flags=8843 metric 0 mtu 1500 > > > > options=8209b > >ether c4:12:f5:33:c9:7c > >inet 192.168.170.5/24 broadcast 192.168.170.255 > >inet6 fe80::c612:f5ff:fe33:c97c%re1/64 scopeid 0x2 > >inet6 2001:470:ecba:3::5/64 > >media: Ethernet autoselect (1000baseT ) > >status: active > >nd6 options=21 > > > I notice your nd6 options do not include ACCEPT_RTADV. Perhaps this > is a reason why your interface is ignoring routing messages? Well, Neighbor Solicitations (ICMPv6 type 135) and Neighbor Advertisements (ICMPv6 type 136) are not exactly routing messages, they are the equivalent of the ARP protocol in IPv6, and AFAIK should work between any two IPv6 nodes to map L3 addresses to L2 addresses, even if there are no routers on the segment. Correct me if I'm wrong. You may be right but then it is certainly a bug. Unfortunately I cannot reproduce the problem with any reliability, this thing works more often than not. > My interface ifconfig shows "nd6 > options=23" > > I also use a statically-defined[*] IPv6 address, but include "accept_rtadv" > in the interface definition in /etc/rc.conf. Furthermore, I also set > rtsold_enable="YES" to send router solicitation messages on the interface. This would add one or two autoconfigured global IPv6 addresses to your interface. There is no harm in that, I agree, but it's important to understand if this is a bug and can be reproduced and reported. > > [*] As well as a static IPv6 address I also enable SLAAC to get > autoconfigured and privacy addresses on the interface. > I see your point, this makes sense, but I would like to try and isolate the problem. -- Victor Sudakov, VAS4-RIPE, VAS47-RIPN 2:5005/49@fidonet http://vas.tomsk.ru/ signature.asc Description: PGP signature
Re: FreeBSD does not reply to IPv6 Neighbor Solicitations
Lutz Donnerhacke wrote: > > Victor Sudakov wrote: > > > Dear Colleagues, > > > > > > Why could it be that a FreeBSD 12.2 host does not reply to ICMPv6 > > > Neighbor Solicitations from the router? > > > > Any ideas please? > > Thank you for pointing this out. > I do have an similar effect, after upgrading, and you point me to a good > direction. > I'll investigate and report back. Problem is, I cannot reproduce it reliably. Sometimes everything "just works." Maybe the absence of traffic causes this, I really don't know. -- Victor Sudakov, VAS4-RIPE, VAS47-RIPN 2:5005/49@fidonet http://vas.tomsk.ru/ signature.asc Description: PGP signature
DNS using Name Service Switch module and Casper
Hello. I wrote a simple daemon called ZeroDNS which provides functionality similar to multicast DNS, namely it discovers other participating machines over the LAN and stores their hostname and IPv4 address pairs. Here is a NSS module which allows the system to use information from that daemon: https://github.com/shamazmazum/nss-zero-dns You need to modify /etc/nsswitch.conf, changing the line 'hosts: files dns' to 'hosts: files dns zerodns'. It all works on FreeBSD 12.2-RELEASE, but sometimes not on 13.0-CURRENT. For example, ping(8) just blocks when trying to ping a host whose name is resolvable with ZeroDNS. Turns out that programs built with casper support (like ping(8) and some others) stop working with my NSS module (they just block trying to resolve the name). Is there some kind of manual on how to write casper-compatible NSS modules? ___ freebsd-net@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"
