review firmware
show version
show remotely connected MAC addresses and how those are being resolved
show mac address-table show mac address-table dynamic show mac address-table interface fa0/X show arp show ip arp
review the logs
show logging history
who’s in?
who show sessions !clear line vty where
review aggregates
show etherchannel
review VLANs
show interfaces trunk show vlan
review more
show connection show flowcontrol show ip interface show ip route
review config
show run show startup-config show running-config show running-config interface show running-config vlan show interface gi0/1 trunk !show archive config diff
review port status
enable show interface status
Interface and Hardware Components Configuration Guide, Cisco IOS XE Fuji 16.9.x (Catalyst 9400 Switches) https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9400/software/release/16-9/configuration_guide/int_hw/b_169_int_and_hw_9400_cg/checking_port_status_and_connectivity.html
Checking Port Status and Connectivity https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/12-2/31sg/configuration/guide/conf/connect.pdf
basic commands https://www.cisco.com/E-Learning/bulk/public/tac/cim/cib/using_cisco_ios_software/07_basic_commands_tasks.htm
Commands to find mac-address and IP on a port https://community.cisco.com/t5/switching/commands-to-find-mac-address-and-ip-on-a-port/td-p/2885631
show interface status https://learningnetwork.cisco.com/s/question/0D53i00000KsxGC/show-interface-status
Cisco switch, how to determine MAC address of connected device or wake device up? https://serverfault.com/questions/338462/cisco-switch-how-to-determine-mac-address-of-connected-device-or-wake-device-up#355555