One of my favorite interview questions to ask network engineering candidates is “How many different ways can you describe to determine the serial number of a Cisco router?”
…and I got to thinking: How many ways do I know how to obtain the serial number of a Cisco router? So I began writing them down and here is what I came up with:
- Locate the serial number tag on the router chassis.
- The serial number is displayed in the banner during boot.
- “show version” command. (Look for “Processor board ID”)
- “show inventory” command. (Look for “Hw Serial#” or “SN:”)
- “show diag” command. (Look for “Chassis Serial Number”)
- “show hardware” command. (Look for “Processor board ID”)
- “show tech-support” command. (Displayed MANY times)
- “show run | s snmp-server chassis-id” command. (Must have been manually set)