The errors logged by Cisco IOS Software frequently provide information about problems occurring on the router or the network in general and should always be checked for pertinent clues when troubleshooting problems. Example 10-42 shows an IS-IS-related logged error that indicates that an address prefix that had a length of 135 bytes was detected, which is more than the expected maximum size. This log information also provides the ID of the LSP carrying the malformed TLV with the bad information. Example 10-43 shows that a hello packet is received from an ATM VC with a length of 51 bytes rather than the expected 53 bytes.
Example 10-44 shows information logged for an adjacency change.