Ed,
Loopback interfaces will by default show up as /32's (see RFC2328 section
9.1) in OSPF. In newer IOS versions (11.3T and 12.0) you can use the
interface configuration command "ip ospf network point-to-point" to have the
loopback advertised with its actual mask as opposed to the /32 (host mask).
Brian Dennis, CCIE #2210 (R&S)(ISP/Dial) CCSI #98640
5G Networks, Inc.
[EMAIL PROTECTED]
(925) 260-2724
> -----Original Message-----
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of
> Ed Dombrowski
> Sent: Monday, May 14, 2001 12:11 PM
> To: [EMAIL PROTECTED]
> Subject: OSPF routing table explanation [7:4448]
>
>
> Below is a routing table from a scenario i am working on. It is for OSPF
> over NBMA in Point-to-Point mode over subinterfaces. It is
> probably an easy
> explanation but something i would like to be clear on. My hub location is
> the 2521 which is where this table is from. I have three routers connected
> to it VIA subinterfaces running through a 2523 acting as the
> switch. I used
> 192.168.1.0 /30 for the wan addresses. On my remote 2501 connected VIA
> Serial0.102 i added loopback interface 1 ip address 192.168.1.33 /27 as i
> wanted to see how the VLSM address showed up in the route table
> of the 2521.
> The table is as follows.
>
> 2521#show ip route
> Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
> D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
> N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
> E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
> i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate
> default
> U - per-user static route, o - ODR
>
> Gateway of last resort is not set
>
> 192.168.1.0/24 is variably subnetted, 4 subnets, 2 masks
> O 192.168.1.33/32 [110/1563] via 192.168.1.6, 00:00:17, Serial0.102
> C 192.168.1.8/30 is directly connected, Serial0.103
> C 192.168.1.12/30 is directly connected, Serial0.104
> C 192.168.1.4/30 is directly connected, Serial0.102
> 2521#
>
> My question is why does the address show up as 192.168.1.33/32 instead of
> /27 as i expected. I have dug around through my books and i
> understand VLSM
> but cant find a simple explanation as to why this shows up as a
> /32 address.
> Can anybody explain this to me?
>
> Thanks,
>
> Ed
> FAQ, list archives, and subscription info:
http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=4468&t=4448
--------------------------------------------------
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
