Hi,
After checking cvs tree, it seems that ospf6d isn't following changes done in
ospfd.
Is someone working on updating ospf6d to add changes done in ospfd ? (or may
be it's not the best way to do ?).
If it's a good idea to do it, I can try. Do you have some advice ? Should I
try to apply a big diff between ospfd initial (i.e. 2007 version) and current
state ? Or is there a way to retrieve each patch made to ospfd between 2007
and now ?
A last question: ospf6d initial version was created by copying and modifying
ospfd files; I presume it was done this way instead of having same code with
#ifdef mecanism for good reasons. After 5 years of evolution, does these
reasons still appear beoing valid (I just ask, I haven't sufficient knowledge
to give an answer).
Manuel
On Sun, 9 Sep 2012 17:14:42 +0200
Manuel Guesdon <ml+openbsd.m...@oxymium.net> wrote:
>| Hi,
>|
>| When an ospf route already exists, ospf6d doesn't update the nexthop.
>| I have 6 routers (4 with openbsd 5.0, 2 with openbsd 4.9) running ospfd,
>| ospf6d and bgpd, routeur id is on lo1.
>|
>| For some reason (see at end for a way to reproduce it), one of the router
>| (openbsd 5.0 one) have multiple ospf ipv6 routes still in fib (even if no
>more
>| ospf6d or bgpd process is running). For exemple:
>|
>| root@core3: route -n get -inet6 XXXX:YYYY::a
>| route to: XXXX:YYYY::a
>| destination: XXXX:YYYY::a
>| gateway: fe80::5054:60ff:fe60:3a1%vlan216
>| interface: vlan216
>| if address: fe80::5054:60ff:fe60:348%vlan216
>| priority: 32 (ospf)
>| flags: <UP,GATEWAY,HOST,DONE>
>| use mtu expire
>| 4200 0 0
>|
>| XXXX:YYYY::a is the loopback address of another router (the gateway is
>| obviously wrong as I've killed ospf6d and bgpd on the referenced host).
>|
>| when starting ospf6d, a new route for XXXX:YYYY::a is found but ospf6d
>| find the previous one and don't change the nexthop. And when killing
>| ospf6d it doesn't remove it.
>|
>| If I "route delete -inet6 -host XXXX:YYYY::a
>| fe80::5054:60ff:fe60:3a1%vlan216", and restart ospf6d the problem disappear.
>|
>| I've took a look at ospf6d/kroute.c and found this route is processed like
>| that:
>|
>| kr_change(struct kroute *kroute)
>| {
>| struct kroute_node *kr;
>| int action = RTM_ADD;
>|
>| kroute->rtlabel = rtlabel_tag2id(kroute->ext_tag);
>|
>| if ((kr = kroute_find(&kroute->prefix, kroute->prefixlen)) !=
>| NULL) {
>| ===> goes here
>|
>| if (!(kr->r.flags & F_KERNEL))
>| action = RTM_CHANGE;
>| else { /* a non-ospf route already exists. not a problem */
>| ===> goes here
>| if (!(kr->r.flags & F_BGPD_INSERTED)) {
>| ===> goes here
>| do {
>| kr->r.flags |= F_OSPFD_INSERTED;
>| kr = kr->next;
>| } while (kr);
>| ===> exit (nexthop is unchanged)
>| return (0);
>| }
>|
>|
>|
>| This problem occurs when the prefix is announced by different
>| ospf peers with a different nexthop. Exemple:
>|
>| When starting ospf6d a first route is added learned from one ospf6d peer:
>|
>| root@core3: route -n get -inet6 XXXX:YYYY::8
>| route to: XXXX:YYYY::8
>| destination: XXXX:YYYY::8
>| gateway: fe80::5054:60ff:fe60:365%vlan222
>| interface: vlan222
>| if address: fe80::5054:60ff:fe60:345%vlan222
>| priority: 32 (ospf)
>| flags: <UP,GATEWAY,HOST,DONE>
>| use mtu expire
>| 0 0 0
>|
>| Next a second route is learned (gateway on fe80::5054:60ff:fe60:321%vlan213
>| which is the most direct route) but ospf6d doesn't update it.
>|
>| Here some traces I've added in ospf6d:
>| MG kr_change: prefix XXXX:YYYY::8/128
>| MG send_rtmsg1: action 1, prefix XXXX:YYYY::8/128
>| MG send_rtmsg2: action 1, nexthop: fe80::5054:60ff:fe60:365
>| ...
>| MG kr_change: prefix XXXX:YYYY::8/128
>| MG kr_change2: found prefix XXXX:YYYY::8/128
>| MG kr_change: prefix XXXX:YYYY::8/128 !FKERNEL
>| MG send_rtmsg1: action 3, prefix XXXX:YYYY::8/128
>| MG send_rtmsg2: action 3, nexthop: fe80::5054:60ff:fe60:321
>| send_rtmsg: action 1, prefix XXXX:YYYY::8/128: File exists
>|
>|
>| After killing ospf6d, (first/bad) route is still here:
>| root@core3:usr.sbin$ route -n get -inet6 XXXX:YYYY::8
>| route to: XXXX:YYYY::8
>| destination: XXXX:YYYY::8
>| gateway: fe80::5054:60ff:fe60:365%vlan222
>| interface: vlan222
>| if address: fe80::5054:60ff:fe60:345%vlan222
>| priority: 32 (ospf)
>| flags: <UP,GATEWAY,HOST,DONE>
>| use mtu expire
>| 28 0 0
>|
>| I've retried multiple times and when the 1st learned route is the good one
>| (via vlan213) the route is well deleted when killing ospf6d.
>|
>|
>| I've tried to compare with ospfd and found that the following chnage seems to
>| handle nexthop change case:
>|
>http://www.openbsd.org/cgi-bin/cvsweb/src/usr.sbin/ospfd/kroute.c.diff?r1=1.52;r2=1.53;f=h
>|
>| May be common changes in ospfd weren't ported to ospf6d ?
>|
>|
>| Manuel
>|
--
Cordialement,
Manuel Guesdon
--
______________________________________________________________________
Manuel Guesdon - OXYMIUM
