If md5 authentication is not deploy the OPSF database descriptor will carry the OSPF_interface_MTU value in the clear. A tool like tshark/wireshark will easily display that value.
In a proper OSPF topology all interfaces attached to the LAN would use the same value. By dumping the OSPF packets you can easily find the Interface MTU value and ospf neighbors that are not configured correctly.
By using a packet.capture you can easily gather statistics without login into numerous routes or devices for gathering ospf show collections
NSE ( network security expert) and Route/Switching Engineer
kfelix -----a----t---- socpuppets ---dot---com
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