Am Montag, 10. Juli 2017, 10:24:43 CEST schrieb Rainer Dorsch: > Hi, > > I added a IPv6 support to a KVM virtualized Jessie system following the > instructions by the hoster > > https://www.netcup-wiki.de/wiki/Zus > %c3%a4tzliche_IP_Adresse_konfigurieren#IPv6%7C > > I my case, I added > > (for me it looks a little weird that IPv4 gets configured via dhcp and IPv6 > is a static configuration, but that is how I read the information in the > wiki. > > After rebooting the system works nicely and shows ipv6 addresses and a > routing table > > root@netcup:~# ip -6 addr show > 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 > inet6 ::1/128 scope host > valid_lft forever preferred_lft forever > 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qlen 1000 > inet6 2a03:4000:6:52b6::/64 scope global > valid_lft forever preferred_lft forever > inet6 fe80::5054:9cff:fe31:f1e0/64 scope link > valid_lft forever preferred_lft forever > root@netcup:~# /sbin/route -6 > Kernel IPv6 routing table > Destination Next Hop Flag Met Ref Use > If > ::1/128 :: U 256 0 0 > ::lo > > 2a03:4000:6:52b6::/64 :: U 256 0 0 > eth0 > fe80::/64 :: U 256 0 0 > eth0 > > ::/0 fe80::1 UGDAe 1024 3 0 > > eth0 > > ::/0 :: !n -1 1 163 > ::lo > ::1/128 :: Un 0 1 36 > ::lo > > 2a03:4000:6:52b6::/128 :: Un 0 7 14 > lo fe80::5054:9cff:fe31:f1e0/128 :: Un 0 1 > 5 lo ff00::/8 :: U 256 10 > 0 eth0 > > ::/0 :: !n -1 1 163 > ::lo > > root@netcup:~# > > After some time (at least hours) the server is not reachable anymore on its > IPv6 address, when connecting on the IPv4 address it seems that the gateway > fe80::1 got lost: > > root@netcup:~# ip -6 addr show > 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 > inet6 ::1/128 scope host > valid_lft forever preferred_lft forever > 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qlen 1000 > inet6 2a03:4000:6:52b6::/64 scope global > valid_lft forever preferred_lft forever > inet6 fe80::5054:9cff:fe31:f1e0/64 scope link > valid_lft forever preferred_lft forever > root@netcup:~# /sbin/route -6 > Kernel IPv6 routing table > Destination Next Hop Flag Met Ref Use > If > ::1/128 :: U 256 0 0 > ::lo > > 2a03:4000:6:52b6::/64 :: U 256 0 0 > eth0 > fe80::/64 :: U 256 0 0 > eth0 > > ::/0 :: !n -1 1 3321 > ::lo > ::1/128 :: Un 0 1 270 > ::lo > > 2a03:4000:6:52b6::/128 :: Un 0 2 670 > lo fe80::5054:9cff:fe31:f1e0/128 :: Un 0 1 > 34 lo ff00::/8 :: U 256 12 > 0 eth0 > > ::/0 :: !n -1 1 3321 > ::lo > > root@netcup:~# > > Rebooting restores the routing table and makes IPv6 working again. > > Has anybody an idea what is going wrong here? Any hint is welcome. >
I wrote a script to detect when the unexpected route change happens: rd@netcup:~$ cat ip6-test.sh Interesting enough around the time when the ipv6 network becomes unreachable Wed Jul 12 23:03:59 CEST 2017, connection ok Wed Jul 12 23:04:29 CEST 2017, connection ok Wed Jul 12 23:04:59 CEST 2017, connection lost
