WALKTHROUGH: OSPF Interace Tuning

Back to the OSPF Interface Tuning Lab

So you're stuck or don't trust your work. Here is the cheat/check page. Note that this is all done from the perspective of J2300-1. Adapt to other routers as needed.

1. Gather debugging info into a file called ospf-int.log

admin@J2300-1> edit 
Entering configuration mode

[edit]
admin@J2300-1# edit protocols ospf traceoptions 

[edit protocols ospf traceoptions]
admin@J2300-1# set file ospf-int.log size 5m 

[edit protocols ospf traceoptions]
admin@J2300-1# set flag error detail 

[edit protocols ospf traceoptions]
admin@J2300-1# commit 
commit complete

[edit protocols ospf traceoptions]
admin@J2300-1# 

2. Change the interface types on your backbone to the type indicated on the diagram

[edit protocols ospf traceoptions]
admin@J2300-1# up 

[edit protocols ospf]
admin@J2300-1# edit area 0 interface fe-0/0/1.12 

[edit protocols ospf area 0.0.0.0 interface fe-0/0/1.12]
admin@J2300-1# set interface-type nbma 

[edit protocols ospf area 0.0.0.0 interface fe-0/0/1.12]
admin@J2300-1# set neighbor 10.0.12.2 

[edit protocols ospf area 0.0.0.0 interface fe-0/0/1.12]
admin@J2300-1# show 
interface-type nbma;
metric 5;
authentication {
    simple-password "$9$RsaSKWN-b2ga69eM8XdV"; ## SECRET-DATA
}
neighbor 10.0.12.2;

[edit protocols ospf area 0.0.0.0 interface fe-0/0/1.12]
admin@J2300-1# up 

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# set interface fe-0/0/1.13 interface-type p2p 

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# commit 
commit complete

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# run show ospf interface  
Interface           State   Area            DR ID           BDR ID          Nbrs
fe-0/0/1.12         Waiting 0.0.0.0         0.0.0.0         0.0.0.0            0
fe-0/0/1.13         PtToPt  0.0.0.0         0.0.0.0         0.0.0.0            0
lo0.0               DR      0.0.0.0         10.0.0.1        0.0.0.0            0
fe-0/0/1.101        BDR     101.101.101.101 10.10.10.10     10.0.0.1           1
fe-0/0/1.102        BDR     102.102.102.102 10.10.10.10     10.0.0.1           1

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# 

3. Stop debugging

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# up 

[edit protocols ospf]
admin@J2300-1# deactivate traceoptions 

[edit protocols ospf]
admin@J2300-1# commit 
commit complete

[edit protocols ospf]
admin@J2300-1# 

4. Examine the tracefile created in the previous step and find an error for an interface type mismatch

admin@J2300-1# run show log ospf-int.log 
Aug 30 09:16:42 trace_on: Tracing to "/var/log/ospf-int.log" started
Aug 30 09:17:40.998939 RPD_OSPF_NBRDOWN: OSPF neighbor 10.0.12.2 (realm ospf-v2 fe-0/0/1.12 area 0.0.0.0) state changed from Full to Down due to KillNbr (event reason: interface went down)
Aug 30 09:17:41.000306 RPD_OSPF_NBRDOWN: OSPF neighbor 10.0.13.3 (realm ospf-v2 fe-0/0/1.13 area 0.0.0.0) state changed from Full to Down due to KillNbr (event reason: interface went down)
Aug 30 09:17:41.015057 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:17:41.015187 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:17:45.592992 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:17:49.592604 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:17:54.626240 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:17:57.414201 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:18:04.288585 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:18:05.539279 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:18:12.808528 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:18:15.501071 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:18:20.229190 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:18:24.049202 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:18:28.316370 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:18:33.315995 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:18:38.279734 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:18:42.903171 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:18:47.673055 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:18:51.509689 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:18:56.147819 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:19:00.893882 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:19:05.875775 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:19:09.307314 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:19:15.545682 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:19:17.026381 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:19:24.310840 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:19:25.860678 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:19:33.657486 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:19:35.327962 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:19:42.865888 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:19:43.406043 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0
Aug 30 09:19:52.441704 OSPF packet ignored: configuration mismatch from 10.0.13.3 on intf fe-0/0/1.13 area 0.0.0.0
Aug 30 09:19:52.741925 OSPF packet ignored: hello interval mismatch 10 from 10.0.12.2 on intf fe-0/0/1.12 area 0.0.0.0

[edit protocols ospf]
admin@J2300-1# 

5. Bring up new OSPF adjacencies with routers R1, R2, R6, R8, R9 and R10 as indicated in the diagram

[edit protocols ospf]
admin@J2300-1# activate traceoptions 

[edit protocols ospf]
admin@J2300-1# commit 
commit complete

[edit protocols ospf]
admin@J2300-1# top           

[edit]
admin@J2300-1# edit interfaces fe-0/0/1 unit 1001 

[edit interfaces fe-0/0/1 unit 1001]
admin@J2300-1# set vlan-id 1001     

[edit interfaces fe-0/0/1 unit 1001]
admin@J2300-1# set family inet address 10.1.111.1/24 

[edit interfaces fe-0/0/1 unit 1001]
admin@J2300-1# commit 
commit complete

[edit interfaces fe-0/0/1 unit 1001]
admin@J2300-1# top 

[edit]
admin@J2300-1# edit protocols ospf area 1        

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# set interface fe-0/0/1.1001 

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# commit 
commit complete

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# run show ospf interface 
Interface           State   Area            DR ID           BDR ID          Nbrs
fe-0/0/1.12         DR      0.0.0.0         10.0.0.1        10.0.0.2           1
fe-0/0/1.13         PtToPt  0.0.0.0         0.0.0.0         0.0.0.0            1
lo0.0               DR      0.0.0.0         10.0.0.1        0.0.0.0            0
fe-0/0/1.101        BDR     101.101.101.101 10.10.10.10     10.0.0.1           1
fe-0/0/1.102        BDR     102.102.102.102 10.10.10.10     10.0.0.1           1
fe-0/0/1.1001       Waiting 0.0.0.1         0.0.0.0         0.0.0.0            0

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# run show ospf interface    
Interface           State   Area            DR ID           BDR ID          Nbrs
fe-0/0/1.12         DR      0.0.0.0         10.0.0.1        10.0.0.2           1
fe-0/0/1.13         PtToPt  0.0.0.0         0.0.0.0         0.0.0.0            1
lo0.0               DR      0.0.0.0         10.0.0.1        0.0.0.0            0
fe-0/0/1.101        BDR     101.101.101.101 10.10.10.10     10.0.0.1           1
fe-0/0/1.102        BDR     102.102.102.102 10.10.10.10     10.0.0.1           1
fe-0/0/1.1001       Waiting 0.0.0.1         0.0.0.0         0.0.0.0            0

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# run monitor start ospf-int.log 

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# 
*** ospf-int.log ***
Aug 30 09:32:58.994593 OSPF packet ignored: hello interval mismatch 1 from 10.1.111.101 on intf fe-0/0/1.1001 area 0.0.0.1
Aug 30 09:32:59.879350 OSPF packet ignored: hello interval mismatch 1 from 10.1.111.101 on intf fe-0/0/1.1001 area 0.0.0.1
Aug 30 09:33:00.863759 OSPF packet ignored: hello interval mismatch 1 from 10.1.111.101 on intf fe-0/0/1.1001 area 0.0.0.1
Aug 30 09:33:01.759242 OSPF packet ignored: hello interval mismatch 1 from 10.1.111.101 on intf fe-0/0/1.1001 area 0.0.0.1
run monitor stop 

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# edit interface fe-0/0/1.1001 

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# set hello-interval 1 

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# commit 
commit complete

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# run show ospf neighbor 
Address          Interface              State     ID               Pri  Dead
10.0.12.2        fe-0/0/1.12            Full      10.0.0.2         128   114
10.0.13.3        fe-0/0/1.13            Full      10.0.0.3         128    35
10.101.0.10      fe-0/0/1.101           Full      10.10.10.10      128    34
10.102.0.10      fe-0/0/1.102           Full      10.10.10.10      128    37

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# run show ospf interface   
Interface           State   Area            DR ID           BDR ID          Nbrs
fe-0/0/1.12         DR      0.0.0.0         10.0.0.1        10.0.0.2           1
fe-0/0/1.13         PtToPt  0.0.0.0         0.0.0.0         0.0.0.0            1
lo0.0               DR      0.0.0.0         10.0.0.1        0.0.0.0            0
fe-0/0/1.101        BDR     101.101.101.101 10.10.10.10     10.0.0.1           1
fe-0/0/1.102        BDR     102.102.102.102 10.10.10.10     10.0.0.1           1
fe-0/0/1.1001       DR      0.0.0.1         10.0.0.1        0.0.0.0            0

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# run monitor start ospf-int.log    

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# 
*** ospf-int.log ***
Aug 30 09:33:35.154046 OSPF packet ignored: dead interval 11 mismatch from 10.1.111.101 on intf fe-0/0/1.1001 area 0.0.0.1
Aug 30 09:33:35.924293 OSPF packet ignored: dead interval 11 mismatch from 10.1.111.101 on intf fe-0/0/1.1001 area 0.0.0.1
Aug 30 09:33:36.895723 OSPF packet ignored: dead interval 11 mismatch from 10.1.111.101 on intf fe-0/0/1.1001 area 0.0.0.1
run monitor stop 

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# set dead-interval 11              

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# commit 
commit complete

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# run show ospf interface 
Interface           State   Area            DR ID           BDR ID          Nbrs
fe-0/0/1.12         DR      0.0.0.0         10.0.0.1        10.0.0.2           1
fe-0/0/1.13         PtToPt  0.0.0.0         0.0.0.0         0.0.0.0            1
lo0.0               DR      0.0.0.0         10.0.0.1        0.0.0.0            0
fe-0/0/1.101        BDR     101.101.101.101 10.10.10.10     10.0.0.1           1
fe-0/0/1.102        BDR     102.102.102.102 10.10.10.10     10.0.0.1           1
fe-0/0/1.1001       BDR     0.0.0.1         10.1.0.1        10.0.0.1           1

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# run show ospf neighbor     
Address          Interface              State     ID               Pri  Dead
10.0.12.2        fe-0/0/1.12            Full      10.0.0.2         128   119
10.0.13.3        fe-0/0/1.13            Full      10.0.0.3         128    31
10.101.0.10      fe-0/0/1.101           Full      10.10.10.10      128    39
10.102.0.10      fe-0/0/1.102           Full      10.10.10.10      128    32
10.1.111.101     fe-0/0/1.1001          Full      10.1.0.1         128    10

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# 

6. Make sure your router never becomes a DR of any sort on the links into areas 0.0.0.1, 0.0.0.2 and 0.0.0.3

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# run show ospf neighbor     
Address          Interface              State     ID               Pri  Dead
10.0.12.2        fe-0/0/1.12            Full      10.0.0.2         128   119
10.0.13.3        fe-0/0/1.13            Full      10.0.0.3         128    31
10.101.0.10      fe-0/0/1.101           Full      10.10.10.10      128    39
10.102.0.10      fe-0/0/1.102           Full      10.10.10.10      128    32
10.1.111.101     fe-0/0/1.1001          Full      10.1.0.1         128    10

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# set priority 0 

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# commit 
commit complete

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# run show ospf interface 
Interface           State   Area            DR ID           BDR ID          Nbrs
fe-0/0/1.12         DR      0.0.0.0         10.0.0.1        10.0.0.2           1
fe-0/0/1.13         PtToPt  0.0.0.0         0.0.0.0         0.0.0.0            1
lo0.0               DR      0.0.0.0         10.0.0.1        0.0.0.0            0
fe-0/0/1.101        BDR     101.101.101.101 10.10.10.10     10.0.0.1           1
fe-0/0/1.102        BDR     102.102.102.102 10.10.10.10     10.0.0.1           1
fe-0/0/1.1001       DRother 0.0.0.1         10.1.0.1        0.0.0.0            1

[edit protocols ospf area 0.0.0.1 interface fe-0/0/1.1001]
admin@J2300-1# 

7. Back off the LSA Retransmission timers on your backbone links to 8 seconds

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# up 

[edit protocols ospf]
admin@J2300-1# edit area 0.0.0.   

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# show 
interface fe-0/0/1.12 {
    interface-type nbma;
    metric 5;
    authentication {
        simple-password "$9$RsaSKWN-b2ga69eM8XdV"; ## SECRET-DATA
    }
    neighbor 10.0.12.2;
}
interface fe-0/0/1.13 {
    interface-type p2p;
    metric 5;
    authentication {
        md5 7 key "$9$ZPjqPQF6/AuEc7VbsJZ9AtOIheKWLNV"; ## SECRET-DATA
    }
}
interface lo0.0;

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# set interface fe-0/0/1.12 retransmit-interval 8 

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# set interface fe-0/0/1.13 retransmit-interval 8 

[edit protocols ospf area 0.0.0.0]
admin@J2300-1#     

8. Speed up the LSA Retransmission timers on your links into areas 0.0.0.1, 0.0.0.2 and 0.0.0.3 by 2 seconds

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# up  

[edit protocols ospf]
admin@J2300-1# edit area 1 

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# set interface fe-0/0/1.1001 retransmit-interval 3 

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# commit 
commit complete

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# 

9. To account for an extremely stable backbone, turn on LSA flood reduction on all Point-to-Point links in area 0.0.0.0

[edit protocols ospf area 0.0.0.1]
admin@J2300-1# up 

[edit protocols ospf]
admin@J2300-1# edit area 0 

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# show 
interface fe-0/0/1.12 {
    interface-type nbma;
    metric 5;
    retransmit-interval 8;
    authentication {
        simple-password "$9$RsaSKWN-b2ga69eM8XdV"; ## SECRET-DATA
    }
    neighbor 10.0.12.2;
}
interface fe-0/0/1.13 {
    interface-type p2p;
    metric 5;
    retransmit-interval 8;
    authentication {
        md5 7 key "$9$ZPjqPQF6/AuEc7VbsJZ9AtOIheKWLNV"; ## SECRET-DATA
    }
}
interface lo0.0;

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# set interface fe-0/0/1.13 flood-reduction 

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# commit 
commit complete

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# 

10. Make sure your router is no longer tracing on OSPF

[edit protocols ospf area 0.0.0.0]
admin@J2300-1# up 

[edit protocols ospf]
admin@J2300-1# delete traceoptions 

[edit protocols ospf]
admin@J2300-1# commit 
commit complete

[edit protocols ospf]
admin@J2300-1# 

Back to the OSPF Interface Tuning Lab

---

Last page update 6 December 2012

OSPF Deep Dive by Blackhole Networks is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
Concerning comments and/or errors, please contact OSPF
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