Hi!
I am observing strange BGP announcement problem.
BGP peering is between bird router (version 2.0.2) and cisco router.
BIRD 10.0.0.1 <---> 10.0.0.2 Cisco
I am announcing prefix 10.10.10.10/32 from bird to cisco.
My initial bird configuration is as follows:
##################
[root@localhost ~]# cat /etc/bird.conf
router id 10.0.0.1;
filter filter1 {
accept;
}
protocol kernel {
persist yes;
learn yes;
scan time 10;
ipv4 {
import none;
export none;
};
}
protocol device {
scan time 10;
}
protocol direct {
interface "lo";
ipv4 {
import filter filter1;
export none;
};
}
protocol bgp peer1 {
local as 65001;
neighbor 10.0.0.2 as 65002;
hold time 45;
ipv4 {
import none;
export filter filter1;
};
}
#####################
IP address 10.10.10.10/32 is configured on loopback interface:
lo:1: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 10.10.10.10 netmask 255.255.255.255
It works just fine with this configuration. I can see announcement of 10.10.10.10/32 on
cisco router:
R1#show ip bgp
Network Next Hop Metric LocPrf Weight Path
*> 10.10.10.10/32 10.0.0.1 0 65001 i
Strange thing happens when I make a change to filter1, instead of:
filter filter1 {
accept;
}
I change it to:
filter filter1 {
if ( net = 10.10.10.10/32 ) then { reject; }
accept;
}
Basically I am blocking import of prefix 10.10.10.10/32 into direct protocol and at the same
time I am blocking export of prefix 10.10.10.10/32 to peer1 (it is the same filter filter1
both for direct import and for peer1 export). After the change of /etc/bird.conf I am making
"birdc configure" and I am expecting to see the withdrawal message on cisco side, but there
is none (I checked it with tcpdump).
Here is what I can still see on cisco side:
R1#show ip bgp
Network Next Hop Metric LocPrf Weight Path
*> 10.10.10.10/32 10.0.0.1 0 65001 i
This is the output of birdc "show route":
bird> show route
bird>
This is the output of birdc "show route export peer1":
bird> show route export peer1
bird>
So there is no route according to bird, but it seems like bird does not send withdrawal
message. Either I am doing something wrong, or it is a bird bug. Appreciate your help.
--
Regards,
Sergey
