Common Show Commands - Cisco IOs

The Show commands display important information about the configuration and operation of the device in the Cisco IOs command Line Interface (CLI) mode. Network administrators use different show commands to examine device status; interfaces, process and configuration files to validate the device operational status. The status of almost all process and function of the router can be view and verify using show command. The important show commands of Cisco IOS are the following:-

• show version
• show running-config
• show arp
• show interfaces
• show protocols
• show ip protocols
• show ip route
• show ip interface brief
• show cdp neighbors

show version

The show version command on Cisco router displays hardware information. The command output gives insight into the routers capabilities. This command can be abbreviated sh ver. The output of show version command consist of following unique information:-

• IOS version
• Image filename
• System uptime
• Type of processor
• Amount of RAM
• Number of ports on the switch
• Amount of flash memory
• Current configuration register

The figure below illustrates the output of the show version command on the Cisco router.

Show running-config

This command is used to display the configuration information currently running on the terminal. We can also use this command in combination with the show startup-config command to compare the information in running memory to the information stored in NVRAM or in a place specified by the CONFIG_FILE. This command can be abbreviated sh ru

show arp

This command displays the ARP table of the router. The ARP table is the table which contains the resolved IPv4 address to MAC address mappings. If a host is can't ping? Make sure using the show arp command that you're getting an arp entry of the host that you want to ping. The command can be abbreviated sh ar .

show interfaces

The show interface command displays all type of interfaces with configuration and statistics. It is very important for the network administrator to know what interfaces are installed and configure in the router. This command provides a lot of information in the output. This command can be abbreviated as sh int.  The figure below illustrates the output of the show interface command.

show protocols

This command displays the status of configured layer three protocols on all interfaces of the Cisco routers. This command can be abbreviated as sh prot

show ip route

The show ip route command is used to show the routing table of the router. The routing table is the list of all networks that the router can communicate; their metrics and how to communicate with them. This command can be abbreviated with sh ip ro. The command also has parameters after route (ro) like sh ip ro rip for all RIP routes. The figure below illustrates the output of the show ip route command

show ip interface brief

The show ip interface brief is one of the most frequently used commands in the Cisco devices. This command provides abbreviated output than the show ip interface command. It provides an outline of the key information for all the network interfaces on a router. The figure below illustrates the output of this command.  The output displays all interfaces on the router; the IP address assigned interfaces, if any, and the operational status of the interface. The show ip interface brief command can also be used to verify the status of the switch interfaces.

Show CDP neighbors

This command display information about the Cisco devices that are connected to your current device. Cisco Discovery Protocol (CDP) is a Cisco proprietary protocol and will only detect Cisco products. To show detailed information about neighboring devices discovered using CDP; use the show cdp neighbors command in privileged EXEC mode. The command can be abbreviated with sh cd ne.