09-22-2017
12:42 PM
- last edited on
03-25-2019
04:45 PM
by
ciscomoderator
All,
Thanks in advance,
I am implementing multi area OSPF in packet tracer and I'm getting weird problems. Please see attached topology image. My area 5 AVVChandler MX84 router which is the area 5 router works just fine, it gets all routes for all networks.
-
AVVCH-MX84#show ip route
Codes: L - local, C - connected, S - static, 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, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 6 subnets, 2 masks
O IA 10.12.0.0/24 [110/3] via 10.12.8.2, 00:06:05, GigabitEthernet0/2
C 10.12.8.0/24 is directly connected, GigabitEthernet0/2
L 10.12.8.1/32 is directly connected, GigabitEthernet0/2
O IA 10.24.0.0/24 [110/3] via 10.12.8.2, 00:06:05, GigabitEthernet0/2
O IA 10.160.213.0/24 [110/3] via 10.12.8.2, 00:06:05, GigabitEthernet0/2
O IA 10.252.0.0/24 [110/2] via 10.12.8.2, 00:06:25, GigabitEthernet0/2
O IA 192.168.128.0/24 [110/3] via 10.12.8.2, 00:06:05, GigabitEthernet0/2
My area 4 MX84 for North Phoenix is working fine generating all routes
When I look at the
:show ip ospf database I can see they is getting all the routes from the ABR.
After double, tripple, and quadruple checking the ABR settings on all my ABR and all my inter-area routers all the config is the same
Now for areas 1, 2, 3 They populate one route from their ABR, which is the area 0 backbone network
AVVSurprise example from mx84
AVVSur-MX84#show ip route
Codes: L - local, C - connected, S - static, 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, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
C 10.12.0.0/24 is directly connected, GigabitEthernet0/2
L 10.12.0.5/32 is directly connected, GigabitEthernet0/2
O IA 10.252.0.0/24 [110/2] via 10.12.0.6, 00:07:55, GigabitEthernet0/2
You can see the neighbor for AVV Surprise MX84
AVVSur-MX84#show ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
5.5.5.5 1 FULL/BDR 00:00:31 10.12.0.6 GigabitEthernet0/2
you can see here it database isn't getting all the routes from it's ABR
AVVSur-MX84#show ip ospf database
OSPF Router with ID (6.6.6.6) (Process ID 1)
Router Link States (Area 3)
Link ID ADV Router Age Seq# Checksum Link count
6.6.6.6 6.6.6.6 699 0x80000002 0x003eaf 1
5.5.5.5 5.5.5.5 699 0x80000002 0x009b58 1
Net Link States (Area 3)
Link ID ADV Router Age Seq# Checksum
10.12.0.5 6.6.6.6 699 0x80000001 0x000119
Summary Net Link States (Area 3)
Link ID ADV Router Age Seq# Checksum
10.252.0.0 5.5.5.5 740 0x80000001 0x009ea4
If you check his ABR AVV Surprise eLAN you see he has all the routes, but he isn't sharing
AVVSurprise-eLAN#show ip ospf database
OSPF Router with ID (5.5.5.5) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
5.5.5.5 5.5.5.5 784 0x80000003 0x007758 1
9.9.9.9 9.9.9.9 784 0x80000003 0x00545a 1
7.7.7.7 7.7.7.7 778 0x80000003 0x00bce0 1
3.3.3.3 3.3.3.3 774 0x80000004 0x00501c 1
1.1.1.1 1.1.1.1 774 0x80000002 0x0081cd 1
Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.252.0.166 9.9.9.9 774 0x80000004 0x0072f2
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.12.0.0 5.5.5.5 814 0x80000001 0x00e94a
10.12.8.0 9.9.9.9 819 0x80000001 0x001903
192.168.128.0 7.7.7.7 819 0x80000001 0x0089ce
10.160.213.0 1.1.1.1 819 0x80000001 0x003b9e
10.24.0.0 3.3.3.3 820 0x80000001 0x00959a
Router Link States (Area 3)
Link ID ADV Router Age Seq# Checksum Link count
5.5.5.5 5.5.5.5 779 0x80000002 0x009b58 1
6.6.6.6 6.6.6.6 779 0x80000002 0x003eaf 1
Net Link States (Area 3)
Link ID ADV Router Age Seq# Checksum
10.12.0.5 6.6.6.6 779 0x80000001 0x000119
Summary Net Link States (Area 3)
Link ID ADV Router Age Seq# Checksum
10.252.0.0 5.5.5.5 820 0x80000001 0x009ea4
AVV Surprise eLAN neighbors
Neighbor ID Pri State Dead Time Address Interface
9.9.9.9 1 FULL/DR 00:00:37 10.252.0.166 GigabitEthernet0/0
1.1.1.1 1 2WAY/DROTHER 00:00:37 10.252.0.71 GigabitEthernet0/0
7.7.7.7 1 FULL/BDR 00:00:37 10.252.0.199 GigabitEthernet0/0
3.3.3.3 1 2WAY/DROTHER 00:00:37 10.252.0.24 GigabitEthernet0/0
6.6.6.6 1 FULL/DR 00:00:37 10.12.0.5 GigabitEthernet0/1
AVVSurprise-eLAN#
AVV Surprise elan config for verification
interface GigabitEthernet0/0
ip address 10.252.0.165 255.255.255.0
duplex auto
speed auto
!
interface GigabitEthernet0/1
ip address 10.12.0.6 255.255.255.0
duplex auto
speed auto
router ospf 1
router-id 5.5.5.5
log-adjacency-changes
network 10.252.0.0 0.0.0.255 area 0
network 10.12.0.0 0.0.0.255 area 3
AVV Surprise MX84 info for verification
interface GigabitEthernet0/2
ip address 10.12.0.5 255.255.255.0
duplex auto
speed auto
router ospf 1
router-id 6.6.6.6
log-adjacency-changes
network 10.12.0.0 0.0.0.255 area 3
Like i said I have double, tripple, and quadruplely checked my config, and it matches with the areas that are working. Kinda going crazy, I feel like packet tracer is acting buggy, please ignore the ASAs they are phase 2 for setting up failover VPN tunnels that are statically set with higher admin distance than ospf for alternate route if elan goes down. Anyone have any thoughts? Sorry for information overload.
I haven't confirmed 100% but when i reload the save i feel the working areas change, and the ones not working correctly change, will need to reload to see if something is weird with packet tracer, thanks again,
Steven
Solved! Go to Solution.
09-25-2017 12:01 PM
Hello,
in your configuration, the routers have different DRs and BDRs. I have set the 'ip ospf priority' on interface GigabitEthernet0/0 on the area 1 ABR to 2, and on the area 2 ABR to 1, the rest of the GigabitEthernet0/0 interfaces has the priority set to 0, so they won't participate in the election. Once that is done, all area 0 routers have the same DR and BDR. And the link state database is consistent across all routers.
09-22-2017 01:25 PM
09-22-2017 01:30 PM
AVVSurprise-eLAN#show ip ospf database summary
OSPF Router with ID (5.5.5.5) (Process ID 1)
Summary Net Link States (Area 0)
LS age: 165
Options: (No TOS-capability, DC, Upward)
LS Type: Summary Links(Network)
Link State ID: 10.12.0.0 (summary Network Number)
Advertising Router: 5.5.5.5
LS Seq Number: 80000003
Checksum: 0xe54c
Length: 28
Network Mask: /24
TOS: 0 Metric: 1
LS age: 170
Options: (No TOS-capability, DC, Upward)
LS Type: Summary Links(Network)
Link State ID: 192.168.128.0 (summary Network Number)
Advertising Router: 7.7.7.7
LS Seq Number: 80000003
Checksum: 0x85d0
Length: 28
Network Mask: /24
TOS: 0 Metric: 1
LS age: 170
Options: (No TOS-capability, DC, Upward)
LS Type: Summary Links(Network)
Link State ID: 10.12.8.0 (summary Network Number)
Advertising Router: 9.9.9.9
LS Seq Number: 80000003
Checksum: 0x1505
Length: 28
Network Mask: /24
TOS: 0 Metric: 1
LS age: 169
Options: (No TOS-capability, DC, Upward)
LS Type: Summary Links(Network)
Link State ID: 10.160.213.0 (summary Network Number)
Advertising Router: 1.1.1.1
LS Seq Number: 80000003
Checksum: 0x37a0
Length: 28
Network Mask: /24
TOS: 0 Metric: 1
LS age: 169
Options: (No TOS-capability, DC, Upward)
LS Type: Summary Links(Network)
Link State ID: 10.24.0.0 (summary Network Number)
Advertising Router: 3.3.3.3
LS Seq Number: 80000003
Checksum: 0x919c
Length: 28
Network Mask: /24
TOS: 0 Metric: 1
Summary Net Link States (Area 3)
LS age: 171
Options: (No TOS-capability, DC, Upward)
LS Type: Summary Links(Network)
Link State ID: 10.252.0.0 (summary Network Number)
Advertising Router: 5.5.5.5
LS Seq Number: 80000003
Checksum: 0x9aa6
Length: 28
Network Mask: /24
TOS: 0 Metric: 1
AVVSurprise-eLAN#
you can't run pipe commands in packet tracer but this is the show run for ospf
router ospf 1
router-id 5.5.5.5
log-adjacency-changes
network 10.252.0.0 0.0.0.255 area 0
network 10.12.0.0 0.0.0.255 area 3
09-22-2017 01:32 PM
Hello,
post the Packet Tracer file, so we can have a look at your configuration...
09-22-2017 01:37 PM
i tried to attach the lab, it doesn't like the extension nor zipped.
09-22-2017 01:50 PM
Change the file extension to .jpg.
The forum was recently altered and doesn't let you upload .pkt files anymore...
09-22-2017 02:27 PM - edited 09-22-2017 05:09 PM
Could you share the output of "show ip route" on AVVSurprise-eLAN ?
I do not see the "Routing Bit is set on this LSA" on all of the LSA 3 routes.
09-25-2017 06:31 AM
09-25-2017 09:10 AM
Hello,
the file is empty. Did you save it is a .pkt and then renamed it to .jpg ?
09-25-2017 09:32 AM
yes, i converted my saved file to a .jpg and uploaded it. I show the .jpg file and the .pkt save on my local computer side by side, they are both 121kb, so uploading it to the site must have messed it up somehow. sorry cisco forums may not be allowing it, i'll attach it again as a jpg here.
09-25-2017 09:33 AM
I just downloaded it from my forum post and converted it back to .pkt and it worked just fine.
09-25-2017 10:35 AM
I got the file. I'll have a look...
09-25-2017 11:41 AM
tysir
09-25-2017 12:01 PM
Hello,
in your configuration, the routers have different DRs and BDRs. I have set the 'ip ospf priority' on interface GigabitEthernet0/0 on the area 1 ABR to 2, and on the area 2 ABR to 1, the rest of the GigabitEthernet0/0 interfaces has the priority set to 0, so they won't participate in the election. Once that is done, all area 0 routers have the same DR and BDR. And the link state database is consistent across all routers.
09-25-2017 12:06 PM
strange, I tried manipulating that by making the router-id on my backbone router higher than all the others and then disconnecting, my studies for CCNA didn't talk alot about priority, but I did wonder about that, thanks for your help. at least all this troubleshooting got me very familar with OSPF for my icnd2 test mid next month, thanks again,
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