Category Archives: CISCO

Downgrade Software on Router That Runs Cisco IOS-XE SD-WAN to Classic Cisco IOS-XE Software

Problem The user cannot configure boot system flash bootflash: image settings in order to boot the original Cisco IOS-XE image: router#config-transaction admin connected from using console on routerrouter(config)# boot ? ^ % Invalid input detected at ‘^’ marker. router(config)# boot system flash bootflash:c1100-universalk9_ias.16.06.05.SPA.bin ——————-^ syntax error: unknown command Solution The procedure is similar to a software… Read More »

Cisco FEX short notes

Fabric Extender Terminology Fabric interface – A 10-Gigabit/40-Gigabit Ethernet uplink port that is designated for connection from the Fabric Extender to its parent switch. A fabric interface cannot be used for any other purpose. It must be directly connected to the parent switch. This interface is enabled when you enter the switchport mode fex-fabric command. Host interface… Read More »


The use of Internet Protocol Security (IPsec) Virtual Tunnel Interfaces (VTIs) simplifies the configuration process when you must provide protection for site-to-site VPN tunnels. A major benefit of IPsec VTIs is that the configuration does not require a static mapping of IPsec sessions to a physical interface. IPsec VTI’s function like any other real interface… Read More »