Command Config-register Use This command is used to modify what configuration files the router reads as it is starting up. This is most commonly used for password recovery purposes. Syntax R1(config)#config-register <value> Optional values 0x2102 This tells the router to startup normally, reading the config in NVRAM 0x2142 …

Command IP Domain-Lookup Use This command allows the router to assume that any non-keyword entered in the command console is supposed to be resolved into an IP address. This is a default command. Most people disable this command as it can be a frequent annoyance to those who …

Command Copy Startup-config TFTP Use This command lets you backup your saved configuration to a remote TFTP server. This is a very common practice. Syntax R1#copy startup-config tftp Example In the below example the saved configuration is backed up to a TFTP server. Copy2611XM#copy start tftp Address or …

Command Terminal Monitor Use This command allows you to see the console output of a router that you are telneted to. Syntax Telnetted_Router#terminal monitor Example In this example, we don’t see any output from the debug ip packet command until the terminal monitor command is entered. CopyR2#debug ip …

Command Copy Startup-config Running-config Use This command lets you merge your saved config with the running configuration. The command overwrites conflicting infomation such as interface IP addresses but keeps new information in the config. Syntax R1#copy startup-config running-config Example In the below example R1’s saved configuration is merged …

Command Copy TFTP Running-config Use This command lets you merge your backed up configuration on a TFTP server with your running configuration.. Syntax Router#copy tftp running-config Example In the below example the backed up configuration on a TFTP server is merged with the running config on the router. …

Command Copy Running-config TFTP Use This command lets you backup your running configuration to a remote TFTP server. Syntax Router#copy running-config tftp Example In the below example the running configuration is copied to a TFTP server. Copy2611XM#copy run tftp Address or name of remote host ? 10.10.2.13 Destination …

Command Copy TFTP Startup-config Use This command lets you copy a configuration that has been backed up on a TFTP server to your startup configuration. Syntax Router#copy tftp startup-config Example In the below example, a backed up configuration is copied to the startup config on the router. Copy2611XM#copy …

Command Undebug All Use This command stops all debugging on the router. Syntax Router#undebug all Example Since there is many different debugging options, we have added a debugging section with some of the more useful debugs for a CCNA candidate. CopyR2#debug ip packet IP packet debugging is on …

Command Write Terminal Use Shows the current configuration of a device. This is deprecated (obsolete) command, but is less typing then using the show run command. This is one of the first commands you will enter when trying to understand how a device is configured. Syntax Router#write terminal …