05-20-2004 01:38 AM - edited 03-02-2019 03:49 PM
Following router/IOS/WAN upgrade OSPF is not advertising the subnet associated with the Loopback interface. It does however advertise the actual Loopback interface address. The subnet associated with the Loopback interface is used for NAT translations.
System image file is "flash:c2600-is-mz.122-23.bin"
interface Loopback0
ip address 172.18.33.1 255.255.255.0
!
interface FastEthernet0/0
ip address 192.168.3.2 255.255.255.0 secondary
ip address 172.16.10.101 255.255.248.0
ip access-group 110 in
no ip redirects
ip nat inside
speed 10
half-duplex
no cdp enable
!
interface BRI0/0
no ip address
ip nat outside
encapsulation ppp
no ip mroute-cache
dialer rotary-group 1
isdn switch-type basic-net3
no fair-queue
no cdp enable
!
interface ATM1/0
description *** 2Mbps CellStream ***
bandwidth 2048
no ip address
no ip mroute-cache
logging event subif-link-status
no atm ilmi-keepalive
scrambling-payload
impedance 120-ohm
!
interface ATM1/0.1 point-to-point
bandwidth 1024
ip address 172.31.5.70 255.255.255.252
ip nat outside
pvc Risley 1/32
vbr-nrt 1024 1024 64000
oam-pvc manage
encapsulation aal5snap
!
!
interface ATM1/0.2 point-to-point
bandwidth 1024
ip address 172.29.1.58 255.255.255.252
ip nat outside
pvc SunGard 1/34
vbr-nrt 1024 1024 64000
oam-pvc manage
encapsulation aal5snap
!
!
interface ATM1/1
no ip address
shutdown
no atm ilmi-keepalive
scrambling-payload
impedance 120-ohm
!
interface ATM1/2
no ip address
shutdown
no atm ilmi-keepalive
scrambling-payload
impedance 120-ohm
!
interface ATM1/3
no ip address
shutdown
no atm ilmi-keepalive
scrambling-payload
impedance 120-ohm
!
interface Dialer1
bandwidth 1
ip address 172.18.48.17 255.255.255.0
ip nat outside
encapsulation ppp
dialer in-band
dialer idle-timeout 300
dialer map ip 172.18.48.1 name foxrtr-ris03 broadcast *****830874
dialer hold-queue 10
dialer-group 1
no fair-queue
no cdp enable
ppp authentication chap
!
router ospf 100
log-adjacency-changes
redistribute connected metric-type 1 subnets
redistribute static
passive-interface FastEthernet0/0
network 172.18.33.0 0.0.0.255 area 0
network 172.18.48.0 0.0.0.255 area 0
network 172.29.1.0 0.0.0.255 area 0
network 172.31.5.0 0.0.0.255 area 0
distribute-list 2 out
!
ip nat pool pj 172.18.33.20 172.18.33.254 netmask 255.255.255.0
ip nat inside source list 1 pool pj
ip nat inside source static 172.16.9.86 172.18.33.14
ip nat inside source static 172.16.8.247 172.18.33.13
ip nat inside source static 172.16.9.97 172.18.33.5
ip nat inside source static 172.16.9.28 172.18.33.4
ip nat inside source static 172.16.9.132 172.18.33.11
ip nat inside source static 172.16.13.24 172.18.33.2
ip nat inside source static 172.16.9.77 172.18.33.7
ip nat inside source static 172.16.9.53 172.18.33.3
ip nat inside source static 172.16.8.75 172.18.33.9
ip nat inside source static 172.16.18.3 172.18.33.12
ip nat inside source static 172.16.9.71 172.18.33.6
ip classless
ip route 0.0.0.0 0.0.0.0 172.18.48.1 150
ip http server
!
access-list 1 permit 192.168.1.0 0.0.0.255
access-list 1 permit 192.168.2.0 0.0.0.255
access-list 1 permit 192.168.3.0 0.0.0.255
access-list 1 permit 192.168.5.0 0.0.0.255
access-list 1 permit 172.16.0.0 0.0.255.255
access-list 2 deny 192.168.3.0
access-list 2 deny 172.16.8.0
access-list 2 deny 172.16.0.0
access-list 2 permit any
05-20-2004 02:57 AM
Under the loopback interface, do this:
ip ospf interface-type point-to-point
And see if that helps. OSPF treats loopback interfaces as virtual interfaces by default, and only advertises the interface address as a /32. Putting this command in tells OSPF to treat the loopback as a point-to-point, and advertise the network address instead.
:-)
Russ.W
05-21-2004 02:16 AM
Unfortunately it didn't have the desired effect.
Although the interface type had changed when viewed using "show ip ospf int" the router is still not generating any Network Link-State advertisements.
Upon further investigation using "show ip ospf database self-originate" only the router Link-State advertisement is being generated.
This smells of an IOS bug but i'm not sure yet.
Marc.T
06-17-2014 11:22 PM
Hi Guys,
Just a quick updates, I encountered the same thing as m.tapping.
Put "ip ospf network point-to-point" as suggested, then "clear ip ospf process".
It works!!! By the way I am using 15.0(1)M8. Hope can help.
Regrads,
ZX
05-24-2004 09:14 PM
Hello, I am currently studying for the CCNP BSCI and i am probably wrong. You are using A NAT inside address of 172.18.33.0 specified in the network command in OSPF and that may be using fast ethernet 0/0 which has a passive interface command assigned to it and passive interfaces do not listen or send updates because the neighbor relationship will not form. I assume that you are using Fast ethernet 0/0 because it has the ip nat inside command on it.The inside subnet is being used for nat translations.
05-24-2004 09:33 PM
continued from above, maybe the subnet is not listed in the nat pool range 20 to 254. I tried. Take care
05-24-2004 11:07 PM
If you can , try to put:
interface Loopback0
ip address 172.18.33.1 255.255.255.255
Use the host address, don't use /24.
05-26-2004 12:11 AM
Did you try issuing the command:
clear ip ospf processes
Sometimes this is necessary to reset OSPF.
05-26-2004 12:17 AM
Thanks, I did try that and it certainly helps to tidy the OSPF protocol after you've been messing with parameters. It did not solve the problem though, it is looking increasingly like an IOS problem.
I even resorted to using "redistribute connected metric-type 1 subnets" and still the loopback stub network is not advertised.
05-26-2004 12:17 AM
Thanks, I did try that and it certainly helps to tidy the OSPF protocol after you've been messing with parameters. It did not solve the problem though, it is looking increasingly like an IOS problem.
I even resorted to using "redistribute connected metric-type 1 subnets" and still the loopback stub network is not advertised.
05-26-2004 12:57 AM
Hi there,
I know you may think this is strange, but have you tried getting rid of the ospf process altogether and then reconfiguring it?
Copy the OPSF config to notepad, and then in global config, use "no router ospf xxx". Then copy it back in. I have had no problem uusing the ip ospf net point-to-p copmmand in order to get a loopback advertised as a network and not a host.
Regards,
Joe
05-26-2004 01:08 AM
Yep, did that too.
I seem to have exhausted most things which is why I think it's IOS.
Difficulty now is finding a different version of IOS for a 2610XM that supports a 'NM-4E1-IMA' module because the online h/w s/w matrix tool does not yet support 2610XM.
Thanks.
05-26-2004 01:20 AM
Have you tried a different loopback number to see if you can get that advertised?
I see what you are trying to do with your NAT, but couldn't you do the same thing with overload, andthe IP address of the FA port?
Joe
05-26-2004 01:28 AM
Just another couple of thoughts. What/where are your OSPF neighbors and how do you know that you are not advertising the loopback correctly? I think you alread did this, but could you post the output from the show ip ospf int command?
I would think that most IOS would automatically support ATM, especially any plus versions.
Joe
05-26-2004 01:38 AM
I ask because the broadast keyword is suspiciously missing from your ATM subinterface config (since like FR ATM is NBMA). Although I can't remember for sure if a point-to-point ospf interface needs this.
Joe
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