[c-nsp] OSPF Exstart problem

[Adil Mansoor]

Hi All,

       This morning I changed the MTU size on our outside facing firewall from 1500 to 9000 on both the inside and outside interface. But the OSPF adjacency on the ouside interface just gets stuck in the EXSTART state and seeing in the error messages I get:



on outside from EXSTART to DOWN, Neighbor Down: Too many DBD retransmissions



I checked for this problem on various forums and CCIE troubleshooting website and found that it all caused because there is a bug in OSPF where change in MTU is not detected and the way around the problem is to issue the command IP OSPF mtu ignore on the interface.

Just need an advice if I should issue the command to get around the problem or is there an issue with the firmware version and that it needs upgrading.

Thanks in advance for any help provided.



Regards,

       Adil



Adil Mansoor
IT Services
ICT Professional - Network Services
t: 0161 247 1466
m: 07748185937
e: a.mansoor at mmu.ac.uk<mailto:a.mansoor at mmu.ac.uk>

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