Disable DNS lookups to prevent CLI delays and enable synchronous logging to prevent log messages from interrupting command input.

Step 1: Disable DNS lookups Prevent the device from attempting to resolve unrecognized commands as hostnames, which causes delays.

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Router>enable
Router#configure terminal
Router(config)#no ip domain-lookup

Step 2: Configure synchronous logging on console Enable logging synchronous on the console line to prevent log messages from interrupting your typing.

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Router(config)#line console 0
Router(config-line)#logging synchronous
Router(config-line)#exit

Step 3: Configure synchronous logging on VTY lines Apply the same logging synchronous setting to remote access sessions (SSH/Telnet).

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Router(config)#line vty 0 15
Router(config-line)#logging synchronous
Router(config-line)#exit
Router(config)#end

Step 4: Verify the configuration

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Router#show running-config | include domain-lookup
Router#show running-config | section line con
Router#show running-config | section line vty

Key Points:

• no ip domain-lookup eliminates 30+ second delays when mistyping commands
• logging synchronous keeps your command prompt clean and readable
• Apply logging synchronous to both console and VTY lines for consistent experience
• These are essential “quality of life” configurations for any Cisco device