Hi,
recently I noticed that ifconfig doesn't handle cloning routes
correctly, if I add/delete ipv6 addresses to interfaces.
After removing an ipv6 address on an interface, the cloning route still
exists. After removing the cloning route by hand, everything seems to be
ok, but after adding the same address again, no cloning route gets
created anymore.
On OpenBSD 5.1 cloning routes get created and deleted correctly with the
ipv6 addresses.
On OpenBSD 5.2 and Current (2012-10-31) the problem occure.
How to reproduce:
[root@ospf2 ~]# ifconfig em3
em3: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
lladdr 08:00:27:7c:76:1b
priority: 0
media: Ethernet autoselect (1000baseT full-duplex)
status: active
inet6 fe80::a00:27ff:fe7c:761b%em3 prefixlen 64 scopeid 0x4
inet 192.168.58.101 netmask 0xffffff00 broadcast 192.168.58.255
// Add ipv6 address to an interface and check routing information:
[root@ospf2 ~]# ifconfig em3 inet6 fd55::5/64
[root@ospf2 ~]# netstat -rn | grep fd55
fd55::/64 link#4 UC
0 0 - 4 em3
fd55::5 08:00:27:7c:76:1b UHL
0 0 - 4 lo0
// It's ok
// delete ipv6 address again
[root@ospf2 ~]# ifconfig em3 inet6 delete fd55::5
[root@ospf2 ~]# netstat -rn | grep fd55
fd55::/64 link#4 UC
0 0 - 4 em3
// XXX: cloning route still exists.
// delete cloning route by hand
[root@ospf2 ~]# route delete -inet6 fd55::/64
delete net fd55::/64
[root@ospf2 ~]# netstat -rn | grep fd55
// It seems to be ok
// Add THE SAME ipv6 address again and check routing information:
[root@ospf2 ~]# ifconfig em3 inet6 fd55::5/64
[root@ospf2 ~]# netstat -rn | grep fd55
fd55::5 08:00:27:7c:76:1b UHL
0 0 - 4 lo0
// XXX: Now the cloning route is missing
// Add missing cloning route by hand
[root@ospf2 ~]# route add -inet6 fd55::/64 -cloning -nostatic -iface
fd55::5
add net fd55::/64: gateway fd55::5
[root@ospf2 ~]# netstat -rn | grep fd55
fd55::/64 link#4 UC
0 0 - 56 em3
fd55::5 08:00:27:7c:76:1b UHL
0 0 - 4 lo0
// It seems to be ok
// Add a different address
[root@ospf2 ~]# ifconfig em3 inet6 fd66::6/64
[root@ospf2 ~]# netstat -rn | grep fd66
fd66::/64 link#4 UC
0 0 - 4 em3
fd66::6 08:00:27:7c:76:1b UHL
0 0 - 4 lo0
// cloning route has been created.
Does anybody know what's the reason for the changed behavior?
A bug in ifconfig or somewhere in the routing table?
Please let me know if further information are required.
Thanks.
friehm
