Show version – This command lists information like the IOS filename and version currently in use. Another very important thing this command shows is the configuration register value The register value 0x2102 is the default factory value. You will need this value, for instance, if you do not know the password on your router. For more information on router passwords, please see my article, How to properly secure your Cisco router with passwords. For more information on the show version, please see the Cisco Use of the Configuration Register on All Cisco Routers documentation.
Show file information – Similar to MS DOS, it displays file information about the specific file.
You must be in EXEC mode to use this command.
Example: Router1#Router# show file information tftp://gener/davis/c3300-d-a.b
type is image (a.out) [relocatable, run from flash]
file size is 8524596 bytes, run size is 9044940 bytes [8512316+112248+420344]
For additional information on the show file information command, see Cisco CFR Commands: show context — show ip http server documentation.
Show host – Display the IP addresses that the Domain Name Server (DNS) uses to resolve the host name.You must be in exec mode to use this command.
Example: R1#show host
name-server-one : 10.3.106.20
name-server-two : 0.0.0.0
domain-name : orchard
For additional information on the show host command, please see the Cisco show commands documentation.