Static Routing - Routing Protocols and Concepts - page 100

To synchronize unsolicited messages and debug output with solicited Cisco IOS Software
output and prompts for a specific console port line, auxiliary port line, or virtual terminal
line, you can use the logging synchronous line configuration command. In other words,
the logging synchronous command prevents IOS messages from being delivered to the
console or Telnet lines from interrupting your keyboard input.

For example, you might have already experienced something similar to the following
example:

Note: Do not configure R1 interfaces yet.

R1(config)# interface fastethernet 0/0
R1(config-if)# ip address 172.16.3.1 255.255.255.0
R1(config-if)# no shutdown
R1(config-if)# descri
*Mar 1 01:16:08.212: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed
state to up
*Mar 1 01:16:09.214: %LINEPROTO-5-UPDOWN: Line protocol on Interface
FastEthernet0/0, changed state to upption
R1(config-if)#

IOS sends unsolicited messages to the console when you activate an interface with the no
shutdown command. However, the next command you enter (in this case, description ) is
interrupted by these messages. The logging synchronous command solves this problem by
copying the command entered up to that point down to the next router prompt.

R1(config)# interface fastethernet 0/0
R1(config-if)# ip address 172.16.3.1 255.255.255.0
R1(config-if)# no shutdown
R1(config-if)# description
*Mar 1 01:28:04.242: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed
state to up
*Mar 1 01:28:05.243: %LINEPROTO-5-UPDOWN: Line protocol on Interface
FastEthernet0/0, changed state to up
R1(config-if)# description <-- Keyboard input copied after message

R1 is shown here as an example. Add logging synchronous to the console and virtual
terminal lines on all routers.

R1(config)# line console 0
R1(config-line)# logging synchronous
R1(config-line)# line vty 0 4
R1(config-line)# logging synchronous

Add the exec-timeout command to the console and virtual terminal lines. Step 4.

To set the interval that the EXEC command interpreter waits until user input is detected,
you can use the exec-timeout line configuration command. This command allows you to
control the amount of time a console or virtual terminal line can be idle before the session
is terminated. The syntax is as follows:

Router(config-line)# exec-timeout minutes [ seconds ]