How to Check the Serial Number of Cisco Products?

Do you have no idea to check your Cisco products’ serial number?

Here share ways to check some models’ serial number, including Cisco routers, Cisco switches, Cisco firewalls, etc.

You may also visit “2024 Revised Edition: How to Check Cisco Product Serial Numbers？” for the latest information.

Table 1. Check the Serial Number of Cisco Products

Router	Buy License, need to check UDI	Buy Smartnet, need to check serial no.	Troubleshooting or return, need to check serial no.
cisco1921/1941	Type command “Show version” or check the box tag, or check serial number at the bottom of device.	Type command “Show version”	Type command “Show version”
cisco 2900 router	Type command “Show version” or check the box tag, or check serial number at the bottom of device.	Type command “Show version”	Type command “Show version”
ISR4221/K9	Type command “Show version” or check the box tag, or check serial number at the bottom of device.	Type command “Show version”	Type command “Show version”
cisco 3900 router	Type command “Show License UDI”	Type command “Show version”	Type command “Show version”
ISR4321/K9	Type command “Show License UDI”	Type command “Show version”	Type command “Show version”
ISR4331/K9	Type command “Show License UDI”	Type command “Show version”	Type command “Show version”
ISR4351/K9	Type command “Show License UDI”	Type command “Show version”	Type command “Show version”
ISR4431/K9	Type command “Show License UDI”	Type command “Show version”	Type command “Show version”
ISR4451-X/K9	Type command “Show License UDI”	Type command “Show version”	Type command “Show version”
Switch	Buy License, need to check UDI	Buy Smartnet, need to check serial no.	Troubleshooting or return, need to check serial no.
2960x	Type command “Show version”	Type command “Show version”	Type command “Show version”
C3850	No registration for this product (RTU license)	Type command “Show version”	Type command “Show version”
C3650	No registration for this product (RTU license)	Type command “Show version”	Type command “Show version”
C9300	Type command “Show version”	Type command “Show version”	Type command “Show version”
C9200	Type command “Show version”	Type command “Show version”	Type command “Show version”
C9400	Type command “Show version”	Type command “Show version”	Type command “Show version”
C9500	Type command “Show version”	Type command “Show version”	Type command “Show version”
Firewall	Buy License, need to check UDI	Buy Smartnet, need to check serial no.	Troubleshooting or return, need to check serial no.
ASA5506	Type command “Sh ver”	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom
ASA5508	Type command “Sh ver”	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom
ASA5516	Type command “Sh ver”	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom
ASA5525	Type command “Sh ver”	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom
ASA5545	Type command “Sh ver”	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom
ASA5585	Type command “Sh ver”	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom
IP Phone	N/A	Buy Smartnet, need to check serial no.	Troubleshooting or return, need to check serial no.
7800 ip phone	N/A	Type command “Show version”	Check serial no. at the box or device’s bottom
8800 ip phone	N/A	Type command “Show version”	Check serial no. at the box or device’s bottom
Wireless AP	Buy License, need to check UDI	Buy Smartnet, need to check serial no.	Troubleshooting or return, need to check serial no.
AP1800/2800/3800	N/A	Type command “Show version”	Check serial no. at the box or device’s bottom
Wireless Controller	Buy License, need to check UDI	Buy Smartnet, need to check serial no.	Troubleshooting or return, need to check serial no.
CT2504	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom
CT3504	No registration for this product (RTU license)	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom
CT5508	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom
CT5520	No registration for this product (RTU license)	Check serial no. at the box or device’s bottom	Check serial no. at the box or device’s bottom

More:

Table 2. the common command of Cisco devices.

Command	Description
terminal length 0	Set terminal display without restriction
show version	View version, equipment running time
show inventory	View serial number SN
show license	View device license
show clock	View device clock information
show fan	View fan
show power	View power
show env all	Check equipment temperature, power supply, fan operating parameters and whether it has alarmed
show cpu	View CPU
show memory	View memory
show bootflash	View flash
show log	View log information
show running-config	View device configuration
show ip protocol	View routing protocol
show ip route	View routing table
show ip route summary	View route summary
show ip interface brief	View the IP simple configuration information of all interfaces
show proc cpu	View CPU
show proc cpu history	View CPU
show proc mem	View memory
dir	View flash
show vlan	View VLAN
show diagbus	View router expansion port information
show module	View switch board information
show buffer	View system cache status
show cdp neighbors	View basic information of linked Cisco devices
show ip ospf neighbors	View OSPF link