Thanks for your replies.
Well, so i have to use the virtual dynamic ipv6 interfaces instead of the DHCPv6 client ones?
I will try out the logging as well.
I am also not sure, which interfaces have to be UP, in order to get it working.
Output from ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: ip6tnl0@NONE: <NOARP> mtu 1452 qdisc noop state DOWN group default qlen 1000
link/tunnel6 :: brd ::
3: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master br-lan state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
4: eth1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 0c:c4:7a:da:b5:d7 brd ff:ff:ff:ff:ff:ff
5: bond0: <BROADCAST,MULTICAST,MASTER> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 76:22:1b:84:89:25 brd ff:ff:ff:ff:ff:ff
6: eth2: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 00:1b:78:5d:cc:32 brd ff:ff:ff:ff:ff:ff
7: eth3: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 00:1b:78:5d:cc:33 brd ff:ff:ff:ff:ff:ff
8: eth4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 00:1b:78:57:bb:0e brd ff:ff:ff:ff:ff:ff
inet6 fe80::21b:78ff:fe57:bb0e/64 scope link
valid_lft forever preferred_lft forever
9: eth5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 00:1b:78:57:bb:0f brd ff:ff:ff:ff:ff:ff
inet6 fe80::21b:78ff:fe57:bb0f/64 scope link
valid_lft forever preferred_lft forever
10: eth6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master br-Trusted state UP group default qlen 1000
link/ether 00:02:c9:06:a5:26 brd ff:ff:ff:ff:ff:ff
11: eth7: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq master br-Trusted state DOWN group default qlen 1000
link/ether 00:02:c9:06:a5:27 brd ff:ff:ff:ff:ff:ff
12: br-Lab: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet 172.20.64.1/19 brd 172.20.95.255 scope global br-Lab
valid_lft forever preferred_lft forever
inet6 2001:4dd0:4ed6::1/60 scope global dynamic noprefixroute
valid_lft 86950sec preferred_lft 86950sec
inet6 2001:4dd0:5033::1/60 scope global dynamic noprefixroute
valid_lft 86836sec preferred_lft 86836sec
inet6 fdfb:9584:eb33::1/60 scope global noprefixroute
valid_lft forever preferred_lft forever
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
13: eth0.2@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-Lab state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
15: br-Management: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet 172.20.32.1/19 brd 172.20.63.255 scope global br-Management
valid_lft forever preferred_lft forever
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
16: eth0.110@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-Management state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
18: br-Trusted: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet 172.20.96.1/19 brd 172.20.127.255 scope global br-Trusted
valid_lft forever preferred_lft forever
inet6 2001:4dd0:4ed6:10::1/60 scope global dynamic noprefixroute
valid_lft 86950sec preferred_lft 86950sec
inet6 2001:4dd0:5033:10::1/60 scope global dynamic noprefixroute
valid_lft 86836sec preferred_lft 86836sec
inet6 fdfb:9584:eb33:10::1/60 scope global noprefixroute
valid_lft forever preferred_lft forever
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
19: eth0.3@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-Trusted state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
20: br-VMs: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet 192.168.200.1/24 brd 192.168.200.255 scope global br-VMs
valid_lft forever preferred_lft forever
inet6 2001:4dd0:4ed6:20::1/60 scope global dynamic noprefixroute
valid_lft 86950sec preferred_lft 86950sec
inet6 2001:4dd0:5033:20::1/60 scope global dynamic noprefixroute
valid_lft 86836sec preferred_lft 86836sec
inet6 fdfb:9584:eb33:20::1/60 scope global noprefixroute
valid_lft forever preferred_lft forever
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
21: eth0.200@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-VMs state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
23: br-lan: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet 192.168.111.1/24 brd 192.168.111.255 scope global br-lan
valid_lft forever preferred_lft forever
inet6 2001:4dd0:4ed6:30::1/60 scope global dynamic noprefixroute
valid_lft 86950sec preferred_lft 86950sec
inet6 2001:4dd0:5033:30::1/60 scope global dynamic noprefixroute
valid_lft 86836sec preferred_lft 86836sec
inet6 fdfb:9584:eb33:30::1/60 scope global noprefixroute
valid_lft forever preferred_lft forever
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
24: eth0.340@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet 172.20.224.1/19 brd 172.20.255.255 scope global eth0.340
valid_lft forever preferred_lft forever
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
25: eth0.320@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet 172.20.192.1/19 brd 172.20.223.255 scope global eth0.320
valid_lft forever preferred_lft forever
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
26: eth0.4@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet 172.21.0.1/19 brd 172.21.31.255 scope global eth0.4
valid_lft forever preferred_lft forever
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
27: eth0.220@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet 172.20.160.1/19 brd 172.20.191.255 scope global eth0.220
valid_lft forever preferred_lft forever
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
28: eth0.300@eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether 0c:c4:7a:da:b5:d6 brd ff:ff:ff:ff:ff:ff
inet 172.21.32.1/19 brd 172.21.63.255 scope global eth0.300
valid_lft forever preferred_lft forever
inet6 fe80::ec4:7aff:feda:b5d6/64 scope link
valid_lft forever preferred_lft forever
29: pppoe-wan: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1492 qdisc fq_codel state UNKNOWN group default qlen 3
link/ppp
inet 78.35.145.32 peer 195.14.226.161/32 scope global pppoe-wan
valid_lft forever preferred_lft forever
inet6 2001:4dd0:af0e:4ed6:15ae:79b2:4399:7882/64 scope global dynamic noprefixroute
valid_lft 2591455sec preferred_lft 604255sec
inet6 fe80::15ae:79b2:4399:7882/128 scope link
valid_lft forever preferred_lft forever
30: pppoe-wanb: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1492 qdisc fq_codel state UNKNOWN group default qlen 3
link/ppp
inet 78.35.146.125 peer 195.14.226.161/32 scope global pppoe-wanb
valid_lft forever preferred_lft forever
inet6 2001:4dd0:af0e:5033:cc19:b4f:8ad:b78f/64 scope global dynamic noprefixroute
valid_lft 2591455sec preferred_lft 604255sec
inet6 fe80::cc19:b4f:8ad:b78f/128 scope link
valid_lft forever preferred_lft forever
31: eth6.2@eth6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-Lab state UP group default qlen 1000
link/ether 00:02:c9:06:a5:26 brd ff:ff:ff:ff:ff:ff
32: eth6.110@eth6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-Management state UP group default qlen 1000
link/ether 00:02:c9:06:a5:26 brd ff:ff:ff:ff:ff:ff
33: eth6.200@eth6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master br-VMs state UP group default qlen 1000
link/ether 00:02:c9:06:a5:26 brd ff:ff:ff:ff:ff:ff