[systemd-devel] DHCPv6 configuration problem

[Thomas Köller]

O.k., I found the problem. The router advertisement is sent from the 
router's link-local address, and therefore the RouterAllowList entry in 
the [IPv6AcceptRA] section was blocking it.

Am 10.02.23 um 13:15 schrieb Thomas Köller:
> Hi,
> 
> 
> I encountered a problem configuring a network interface via DHCPv6, 
> using the attached .network file. The interface does receive router 
> announcements with the 'managed' flag set, as indicated by the following 
> tcpdump output:
> 
> [root at raspi-400 ~]# tcpdump -i vpn_sarkovy -v '(icmp6 and (ip6[40] == 
> 133 or ip6[40] == 134)) or (udp and (port 546 or port 547))'
> dropped privs to tcpdump
> tcpdump: listening on vpn_sarkovy, link-type EN10MB (Ethernet), snapshot 
> length 262144 bytes
> 12:50:04.037114 IP6 (flowlabel 0x34393, hlim 255, next-header ICMPv6 
> (58) payload length: 112) _gateway > ff02::1: [icmp6 sum ok] ICMP6, 
> router advertisement, length 112
>      hop limit 0, Flags [managed, other stateful], pref medium, router 
> lifetime 7200s, reachable time 0ms, retrans timer 0ms
>        source link-address option (1), length 8 (1): 02:19:55:00:00:01
>        prefix info option (3), length 32 (4): fd46:1ffa:d8e0::/48, Flags 
> [onlink, auto], valid time 3600s, pref. time 1800s
>        rdnss option (25), length 24 (3):  lifetime 3600s, addr: 
> sarkovy.koeller.dyndns.org
>        dnssl option (31), length 32 (4):  lifetime 3600s, domain(s): 
> koeller.dyndns.org.
> 
> This, however, does not trigger a DHCPv6 exchange with the server.
> 
> 
> The client computer is multi-homed, and for the other interface 
> everything works as expected. Any help with this is greatly appreciated.
> 
> 
> Thomas
> 

-- 
Thomas Köller
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