Hello,

I just set up two identical machines to make some tests with vlan, carp 
and openbgpd to replace my cisco routers in the next couple of months. 
VLAN- and carp-configuratin is quite easy, it works out of the box and 
without any problems. OpenBGPd runs fine, too. Err, nearly fine.

I named my two boxes Pinky and Brain :) On both I configured the same 
VLAN and CARP - this should be the local gateways for the other boxes 
connected using a normale cisco switch. I pasted the output of the 
ifconfig command to the bottom of this mail.

To reach some kind of redundancy I set up an iBGP-Session between Pinky 
and Brain. It is a very simple configuration and has only minor 
differences - you can find the complete configuration file at the bottom 
of the mail:

< router-id             194.9.86.1
 > router-id             194.9.86.2

< neighbor 194.9.86.2 {
 > neighbor 194.9.86.1 {

<       local-address   194.9.86.1
 >       local-address   194.9.86.2

I expect to receive the specifed network-prefix from Pinky on Brain via 
iBGP and vice versa. But on Brain I can't find any advertised prefix 
from Pinky:

Pinky# bgpctl sh 
 

Neighbor             AS    MsgRcvd    MsgSent    OutQ  Up/Down 
State/PrefixRcvd
Brain                35548          8          7     0 00:04:23      0

The other side works fine, Brain is receiving the prefix from Pinky.
Brain# bgpctl sh 
 

Neighbor             AS    MsgRcvd    MsgSent    OutQ  Up/Down 
State/PrefixRcvd
Pinky                35548          6          7     0 00:03:11      1

Both sides advertises the prefix, I can't find any misconfiguration on 
this. Brain advertises the prefix as you can see here:

Brain# bgpctl sh rib 
 

flags: * = Valid, > = Selected, I = via IBGP, A = Announced
origin: i = IGP, e = EGP, ? = Incomplete

flags destination         gateway          lpref   med aspath origin
I*>   195.140.212.0/23    194.9.86.1         100     0 i
AI*   195.140.212.0/23    0.0.0.0            100     0 i


But I don't received it on Pinky (as you can see above):

Pinky# bgpctl sh rib
flags: * = Valid, > = Selected, I = via IBGP, A = Announced
origin: i = IGP, e = EGP, ? = Incomplete

flags destination         gateway          lpref   med aspath origin
AI*>  195.140.212.0/23    0.0.0.0            100     0 i


Does anybody has an explanation for this behaviour? I tried without any 
vlan and carp interface only with "normal" configured interfaces - the 
same. I'm at a loss. You are my last hope :-))


Regards,

Falk

--snipp--
Output of the ifconfig command:

##Pinky:
vlan212: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
         lladdr 00:06:5b:ec:48:c5
         vlan: 212 priority: 0 parent interface: em1
         groups: vlan
         inet6 fe80::206:5bff:feec:48c5%vlan212 prefixlen 64 scopeid 0x9
         inet 195.140.212.2 netmask 0xffffffff broadcast 195.140.212.2
carp212: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
         lladdr 00:00:5e:00:01:d4
         carp: MASTER carpdev vlan212 vhid 212 advbase 1 advskew 0
         groups: carp
         inet6 fe80::200:5eff:fe00:1d4%carp212 prefixlen 64 scopeid 0xe
         inet 195.140.212.1 netmask 0xffffff00 broadcast 195.140.212.255

##Brain:
vlan212: flags=8943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST> mtu 1500
         lladdr 00:0f:1f:66:3f:d3
         vlan: 212 priority: 0 parent interface: em1
         groups: vlan
         inet6 fe80::20f:1fff:fe66:3fd3%vlan212 prefixlen 64 scopeid 0x9
         inet 195.140.212.3 netmask 0xffffffff broadcast 195.140.212.3
carp212: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
         lladdr 00:00:5e:00:01:d4
         carp: BACKUP carpdev vlan212 vhid 212 advbase 1 advskew 0
         groups: carp
         inet6 fe80::200:5eff:fe00:1d4%carp212 prefixlen 64 scopeid 0xf
         inet 195.140.212.1 netmask 0xffffff00 broadcast 195.140.212.255


--snipp--
The complete configuration file:

##Pinky:
# global configuration
AS 35548
router-id               194.9.86.1
network                 195.140.212.0/23

holdtime                180
holdtime min            3

neighbor 194.9.86.2 {
         remote-as       35548
         descr           Brain
         local-address   194.9.86.1
         announce        all
         tcp md5sig key  foobar
}

# filter out prefixes longer than 24 or shorter than 8 bits
deny from any
allow from any prefixlen 8 - 24

# do not accept a default route
deny from any prefix 0.0.0.0/0

# filter bogus networks
deny from any prefix 10.0.0.0/8 prefixlen >= 8
deny from any prefix 172.16.0.0/12 prefixlen >= 12
deny from any prefix 192.168.0.0/16 prefixlen >= 16
deny from any prefix 169.254.0.0/16 prefixlen >= 16
deny from any prefix 192.0.2.0/24 prefixlen >= 24
deny from any prefix 224.0.0.0/4 prefixlen >= 4
deny from any prefix 240.0.0.0/4 prefixlen >= 4

##Brain:
# global configuration
AS 35548
router-id               194.9.86.2
network                 195.140.212.0/23

holdtime                180
holdtime min            3

neighbor 194.9.86.1 {
         remote-as       35548
         descr           Pinky
         local-address   194.9.86.2
         announce        all
         tcp md5sig key  foobar
}

# filter out prefixes longer than 24 or shorter than 8 bits
deny from any
allow from any prefixlen 8 - 24

# do not accept a default route
deny from any prefix 0.0.0.0/0

# filter bogus networks
deny from any prefix 10.0.0.0/8 prefixlen >= 8
deny from any prefix 172.16.0.0/12 prefixlen >= 12
deny from any prefix 192.168.0.0/16 prefixlen >= 16
deny from any prefix 169.254.0.0/16 prefixlen >= 16
deny from any prefix 192.0.2.0/24 prefixlen >= 24
deny from any prefix 224.0.0.0/4 prefixlen >= 4
deny from any prefix 240.0.0.0/4 prefixlen >= 4