Re:_ DHCPv6_IA_PD_-_how-to

 ---- On Thu, 01 Aug 2024 16:24:54 +0100  Chris Ross  wrote --- 
 > 
 > [Long message, apologies.  Thoughts mostly after the log output.]
 > 
 > > On Jul 24, 2024, at 04:12, Roy Marples roy@marples.name> wrote:
 > > dhcpcd can indeed setup the internal networks within the PD for you.
 > > If my answer to Kar's question is not enough, then please let me know.
 > 
 > Alright.  Time passes, and I have a new system (FreeBSD 14.1) reach to
 > slot in in place of my old router (FreeBSD 11.4).  With Roy’s help
 > off-list, I have a config that I think will work:
 > 
 > duid
 > persistent
 > vendorclassid
 > option classless_static_routes
 > option rapid_commit
 > require dhcp_server_identifier
 > slaac private
 > noipv6rs
 > interface vlan0
 >   ipv6only
 >   noipv4
 >   noipv4ll
 >   ia_pd 0/::/56 vlan1/32 vlan2/42 vlan3/52 vlan4/62 vlan5/72 vlan6/82 vlan7/92
 > 
 > I brought the system up as an IPv4 router with no IPv6 configured,
 > then ran “dhcpcd --noconfigure -d -B”. Output is long, but select
 > bits (including top and bottom) show:
 > 
 > ——8<——8<——8<——8<----
 > main: control_open: Connection refused
 > dhcpcd-10.0.8 starting
 > spawned privileged proxy on PID 43738
 > spawned network proxy on PID 43930
 > spawned controller proxy on PID 44915
 > DUID 00:01:00:01:2e:3e:5e:7f:a4:53:0e:79:b9:82
 > sandbox unavailable: capsicum

OK, that's bad.
This means that the cap_enter(3) failed so your kernel was not built with CAPABILITY_MODE enabled.

 > lo0: ignoring due to interface type and no config
 > pflog0: unsupported interface type 0xf6
 > ix0: executing: /usr/local/libexec/dhcpcd-run-hooks PREINIT
 > ix0: executing: /usr/local/libexec/dhcpcd-run-hooks CARRIER
 > ix1: executing: /usr/local/libexec/dhcpcd-run-hooks PREINIT
 > vlan0: executing: /usr/local/libexec/dhcpcd-run-hooks PREINIT
 > vlan0: executing: /usr/local/libexec/dhcpcd-run-hooks CARRIER
 > vlan1: executing: /usr/local/libexec/dhcpcd-run-hooks PREINIT
 > vlan1: executing: /usr/local/libexec/dhcpcd-run-hooks CARRIER
 > vlan2: executing: /usr/local/libexec/dhcpcd-run-hooks PREINIT
 > vlan2: executing: /usr/local/libexec/dhcpcd-run-hooks CARRIER
 > vlan3: executing: /usr/local/libexec/dhcpcd-run-hooks PREINIT
 > […]
 > vlan0: IAID ff:00:00:06
 > vlan0: IA type 25 IAID 00:00:00:00
 > vlan0: reading lease: /var/db/dhcpcd/vlan0.lease6
 > vlan0: rebinding prior DHCPv6 lease
 > vlan0: delaying REBIND6 (xid 0x329d93), next in 1.0 seconds
 > vlan0: multicasting REBIND6 (xid 0x329d93), next in 1.1 seconds
 > vlan0: REPLY6 received from fe80::3e8a:b0ff:fe3e:4dce
 > vlan0: renew in 3600, rebind in 5760, expire in 7200 seconds
 > vlan0: writing lease: /var/db/dhcpcd/vlan0.lease6
 > vlan0: executing: /usr/local/libexec/dhcpcd-run-hooks REBIND6
 > […]
 > vlan6: executing: /usr/local/libexec/dhcpcd-run-hooks BOUND
 > vlan5: DAD completed for 192.168.123.46
 > vlan5: leased 192.168.123.46 for 3105 seconds
 > vlan5: renew in 1552 seconds, rebind in 2716 seconds
 > vlan5: writing lease: /var/db/dhcpcd/vlan5.lease
 > vlan5: executing: /usr/local/libexec/dhcpcd-run-hooks BOUND
 > vlan2: DAD completed for 172.31.83.42
 > vlan2: leased 172.31.83.42 for 755 seconds
 > vlan2: renew in 377 seconds, rebind in 660 seconds
 > vlan2: writing lease: /var/db/dhcpcd/vlan2.lease
 > vlan2: executing: /usr/local/libexec/dhcpcd-run-hooks BOUND
 > ix0: ARP probing 169.254.156.162 (2 of 3), next in 1.8 seconds
 > ix1: ARP probing 169.254.188.53 (2 of 3), next in 1.7 seconds
 > ps_bpf_recvmsg: Network is down
 > vlan1: ARP probing 169.254.156.162 (3 of 3), next in 2.0 seconds
 > ix0: ARP probing 169.254.156.162 (3 of 3), next in 2.0 seconds
 > ix1: ARP probing 169.254.188.53 (3 of 3), next in 2.0 seconds
 > ps_bpf_recvmsg: Network is down
 > vlan1: using IPv4LL address 169.254.156.162
 > zsh: segmvlan3ation fault  sudo dhcpcd --noconfigure -d -B

eek, that's worse!
Fixed here: https://github.com/NetworkConfiguration/dhcpcd/commit/c6a8fa1e6a68e46e89fef0f953f4c7bf4915e257
You can work around the issue by adding noipv4ll to your config.

 > I’m sure there are “stupid user tricks” here.  I think the
 > primary problem is that it’s using more than the one interface
 > I want it to.  It also looks like it’s picking up IPv4 addresses
 > from the local ISC dhcpd on all of the other interfaces.  I’m
 > glad it wasn’t trying to configure them!

Yes.
You can limit what interfaces dhcpcd works with using a combination of allowinterfaces and denyinterfaces directives as described in dhcpcd.conf(5).
Or you can give the explicit list of interfaces on the command line. If only one interface, you should use the -M option until dhcpcd-11 is finished.
If PD needs any interfaces you have denied, they will be activated solely for PD.

  > Then, of course, the SEGV.  So, first I guess I need to tell
 > it to not try interfaces other than the one I want.  For my
 > case.  However there are a few things I think may want to
 > be worked on:
 > 
 > 1. The SEGV, obviously
 > 2. It seems to be trying things on ix1, despite no carrier.
 > I understand keeping an eye on it, but not sending DISCOVER
 > and ARP et al.
 > 3. It seems it shouldn’t accept a DHCP address from it’s
 > local address.  I question if it should try to _get_ an
 > address if there’s already an address, but.  Maybe this
 > is a dhcpd problem, where it shouldn’t respond to requests
 > from the local address?
 > 

1. Fixed with the referenced commit. Please apply to your version.
2. I don't see any carrier stuff as you snipped parts of the log. Email to me privately no matter how large. Good you enabled debugging.
3. I don't understand the question or problem? Can you try to rephrase?

Thanks

Roy