[Xorp-users] OSPF network advertisements
Andy Bavier
acb@cs.princeton.edu
Tue, 04 Apr 2006 13:59:19 -0400
Hi,
I am trying to configure XORP to advertise routes to a local network
using OSPF. My problem is that only the interface *address* appears to
be advertised, and not the entire network -- in other words, only a /32
address is inserted into the routing table and not a /24. My question
is, how to get OSPF to advertise and route to the /24?
My OSPF configuration looks like this. Interface 'eth0' is on a /24
network. I expected that by setting eth0 as 'passive' I could get OSPF
to advertise routes for the attached network, without actually running
OSPF on this interface:
protocols {
ospf4 {
router-id: 128.112.139.96
area 0.0.0.0 {
interface eth0 {
vif eth0 {
address 10.32.11.2 {
interface-cost: 1
passive: true
}
}
}
interface eth1 {
vif eth1 {
address 192.168.1.2 {
interface-cost: 1
}
}
}
interface eth2 {
vif eth2 {
address 192.168.2.2 {
interface-cost: 1
}
}
}
}
}
}
OSPF appears to be working correctly, and 'eth0' is being advertised.
However, all of the installed routes have masks of 255.255.255.255:
# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use
Iface
192.168.1.2 192.168.2.2 255.255.255.255 UGH 1 0 0 eth2
192.168.2.2 192.168.2.2 255.255.255.255 UGH 1 0 0 eth2
10.32.11.2 192.168.2.2 255.255.255.255 UGH 1 0 0 eth2
[...]
From what I can tell, it looks like this mask is being propagated in
the LSAs themselves:
root@planetlab-3.cs.princeton.edu> show ospf4 database detail
OSPF link state database, Area 0.0.0.0
Router-LSA:
LS age 283 Options 0x2 DC: 0 EA: 0 N/P: 0 MC: 0 E: 1 LS type 0x1 Link
State ID 128.112.139.96 Advertising Router 128.112.139.96 LS sequence
number 0x80000002 LS checksum 0x7da7 length 72
Nt-bit false
V-bit false
E-bit false
B-bit false
Type 3 Stub network Subnet number 10.32.11.2 Mask
255.255.255.255 Metric 0
Type 3 Stub network Subnet number 192.168.1.2 Mask
255.255.255.255 Metric 0
Type 3 Stub network Subnet number 192.168.2.2 Mask
255.255.255.255 Metric 0
Does anyone have insights or suggestions on what I need to do to
advertise a 255.255.255.0 netmask for eth0?
Thanks,
Andy