DHCPv6-PD doesn't work. DHCPv6-server won't start after commiting configuration

Bugs
, ,
1

Hi,

I am using VyOS version:

vyos@vyos:~$ show version 
Version:          VyOS 1.3.1
Release train:    sagitta
Built by:         derago@gmail.com
Built on:         Thu 14 Apr 2022 14:19 UTC
Build UUID:       4de5e5e1-16f2-4a5b-a142-4c435d503018
Build commit ID:  5fa31bdccc8bdf
Architecture:     x86_64
Boot via:         installed image
System type:      bare metal

I tried to configure DHCPv6-PD with the following config:

vyos@vyos# show service dhcpv6-server 
 shared-network-name networkname-dhcpv6 {
     subnet 20xx:xxx:xxx:c0::/60 {
         name-server 2001:4860:4860::8888
         prefix-delegation {
             start 20xx:xxx:xxx:d0::100 {
                 prefix-length 64
                 stop 20xx:xxx:xxx:d0::200
             }
         }
     }
 }

And commit works but then when I try to restart dhcpv6-server I get:

vyos@vyos:~$ restart dhcpv6 server 
Job for isc-dhcp-server6.service failed because the control process exited with error code.
See "systemctl status isc-dhcp-server6.service" and "journalctl -xe" for details.

I could post what’s in the journalctl but there is really nothing there. I configured IPv6 in the range of the prefix configured on that interface and IPv6 connectivity is working:

vyos@vyos:~$ show interfaces ethernet eth2 
eth2: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN group default qlen 1000
    link/ether 5c:a6:e6:xx:xx:xx brd ff:ff:ff:ff:ff:ff
    inet6 20xx:xxx:xxx:c0::1/60 scope global

I suspect there is some bug. But if someone more experienced in VyOS could shed a light a bit I would be glad. Thanks!

EDIT: But since the server won’t start there is no DHCPv6 leases yet!

2

Hi @ITGUY , it is not 1.3.1 because Release train: sagitta. You built 1.4 and named it 1.3.1
Let me try to reproduce on 1.4 rolling and maybe it is necessary to describe this bug on the development portal.

3

In our original 1.3.2 I can not confirm any bugs regarding DHCPv6 server

vyos@vyos:~$ show version | match "Version|Release"
Version:          VyOS 1.3.2
Release train:    equuleus
vyos@vyos:~$ show configuration commands | match dhcpv6
set service dhcpv6-server shared-network-name NET1 subnet 2001:db8::/64 address-range start 2001:db8::100 stop '2001:db8::199'
set service dhcpv6-server shared-network-name NET1 subnet 2001:db8::/64 name-server '2001:db8::ffff'
vyos@vyos:~$ restart dhcpv6 server 
vyos@vyos:~$ ps ax | grep dhcp
 2440 ?        Ss     0:00 /usr/sbin/dhcpd -6 -q -user dhcpd -group nogroup -pf /run/dhcp-server/dhcpdv6.pid -cf /run/dhcp-server/dhcpdv6.cons
 2442 ttyS0    S+     0:00 grep dhcp

UPD: On the latest rolling all works properly

vyos@vyos:~$ show version | match "Version|Release"
Version:          VyOS 1.4-rolling-202210050218
Release train:    sagitta
4

Hi @Dmitry,
Without PD in config my DHCPv6 server also starts. Please take a look at subnets and prefixes in my config. The subnet is c0::/60 and PD is from d0::/64 range. Could you confirm it works for you as well. If so I will try to upgrade to official nightly builds.

5

Yes, confirmed. Looks like it is know issue with missing prefix validation

https://phabricator.vyos.net/T3493

1 Like
6

Is there some timeline to fix that bug? Some milestone? It’s there already since 2021 :frowning: