Here the command equivalences of network command that shows the corresponding old and new versions of the commands. Most people find the new set of commands more logical and prefer using the new ones. However, old habits are difficult to break, and because the old syntax is supported, people still type write mem instead of copy running startup.

Command Equivalences LAN Network

Old-Style (Pre 10.3) Commands                                        New-Style (10.3 and Later) Commands
Configure terminal                                                            configure terminal
Configure memory                                                            copy startup-config running-config
Configure network                                                            copy tftp running-config
Configure overwrite-network                                             copy tftp startup-config
write terminal                                                                   show running-config
write memory                                                                   copy running-config startup-config
write network                                                                   copy running-config tftp
write erase                                                                       erase startup-config
show configuration                                                            show startup-config

An important detail about making changes to the router’s active configuration is that the new configuration file does not substitute the current settings as occurs during a file copy operation. Rather, new commands are merged with the existing settings. It is usually no problem to understand the manual changes made using the “configure terminal command”. However, people tend to incorrectly imagine the way the copy startup-config running-config and the copy tftp running-config commands work as substitution.

Consider an example. The following is the initial configuration of a router’s interface Serial0:

interface serial 0

 no ip address

 shutdown

It is updated with following configuration file on a TFTP server:

interface serial 0

 ip address 10.1.1.1 255.255.255.0