Show Command List (Basic) and Interface Numbering Facts

Show Command List (Basic)

The following list summarizes common information you can display using common show commands.

Use this command...	To...
show version	View hardware configuration, running IOS version, ROM bootstrap version, and RAM and processor information
show running-config	View the currently running configuration file
show startup-config or show config	View the startup configuration file stored in NVRAM (the saved copy of the configuration file)
show flash	View the size of the configuration files and the available flash memory View information for all IOS image files stored on the router
show history	View the commands in the command history list
show protocols or show interfaces or show ip interfaces	View the IP addresses assigned to a specific interface
show protocols or show interfaces	View the status of all interfaces

 

Interface Numbering Facts

The switch interface numbering scheme includes the bank number and port number:

Portion	Details	Examples
Bank number	Switches that have one fixed bank are assigned 0. Switches that have multiple banks start with 0 and are assigned from bottom to top. For example, if a switch had 5 banks, it would have bank numbers 0-4.	FastEthernet 2/1 (3rd bank/1st port) FastEthernet 1/5 (2nd bank/5th port) FastEthernet 0/7 (fixed bank or 1st bank/7th port) FastEthernet 5/1 (6th bank/1st port)
Port number	Port numbers are assigned starting with 1. Switches that have 1 row of ports on a bank are assigned from left to right. Switches that have 2 rows of ports on a bank are assigned from top to bottom and left to right.

Router interface numbering includes the following types of schemes:

Scheme	Details	Examples
Fixed ports	Older Cisco routers, such as the Cisco 2500, use a fixed port numbering scheme. In the fixed port numbering scheme: Each built-in port was hard-wired with a port number. Numbering starts with 0, and is assigned from right to left.	Serial0 (1st serial port) Serial1 (2nd serial port) Ethernet0 (1st Ethernet port)
Slot/Port numbering	Newer Cisco routers, such as the Cisco 2600, support WAN Interface Cards (WIC) and Network Modules (NM) with various ports. Some Network Modules include slots for WAN Interface Cards. In the Slot/Port numbering scheme: The slot number scheme includes:   Built-in ports and built-in WIC slots are given NM slot number 0. The remaining NM slots are assigned from right to left and bottom to top. If the device does not have built-in ports or built-in WIC slots, the NM slot numbering is assigned from right to left and bottom to top, starting with 0. Note: When learning about the router's NM slots, discover whether or not the router has built-in ports and built-in WIC slots. The port numbers start with 0 and are assigned from right to left and bottom to top for each NM slot.	FastEthernet3/4 (3rd NM slot/5th FastEthernet port) FastEthernet0/3 (built-in/4th FastEthernet port) Serial2/3 (2nd NM slot/4th serial port) Serial1/5 (1st NM slot/6th serial port) Serial0/2 (built-in or 1st WIC slot/3rd serial port)
Slot/Sub-slot/Port numbering	The newest Cisco routers, such as the Cisco 1800/2800/3800, use an enhanced slot/port numbering scheme to identify the WIC sub-slot.  In the Slot/Sub-slot/Port numbering scheme: Built-in WIC ports are numbered using a slot of 0 and a sub-slot that is the WIC slot number. WIC ports on a NM slot are numbered using the NM slot number and the WIC's sub-slot number on the NM. Ports (other than those of a WIC) use the slot/port numbering scheme.	FastEthernet2/1/0 (2nd NM slot/2nd WIC sub-slot/1st FastEthernet port) FastEthernet0/0/0 (built-in/1st WIC sub-slot/1st FastEthernet port) FastEthernet0/1/3 (built-in/2nd WIC sub-slot/4th FastEthernet port) Serial4/1/1 (4th NM slot/2nd WIC sub-slot/2nd Serial port) Serial0/1/0 (built-in/2nd WIC sub-slot/1st Serial port) Ethernet1/0 (1st NM slot/1st Ethernet port) FastEthernet0/1 (built-in/2nd FastEthernet port)