Cisco Certification Exam Review:
async mode dedicated vs. async mode interactive
By Chris Bryant, CCIE #12933
These commands are commonly confused, so let's take an in-depth look at them. To place a line into dedicated asynchronous network mode, run async mode dedicated.
Sounds simple enough, right? While the command async mode dedicated places a line into dedicated async mode using SLIP or PPP, it does disable the slip and ppp EXEC commands. Actually, there will be no exec prompt at all - the user will not be able to interact with the router as might be desired.
To put a line back into interactive mode - which enables the slip and ppp exec commands - use the async mode interactive command. (You can also run no async mode dedicated.) The use of both commands is shown below.
To assign PPP features such as CHAP to a line, use interface async X, with x representing the line number.
164(config)#int async 2
164(config-if)#encap ppp
164(config-if)#ppp authentication chap
164(config-if)#async mode ?
dedicated Line is dedicated as an async interface
interactive Line may be switched between interactive use and async interface
164(config-if)#async mode
Typical async interface values: encapsulation, authentication (as shown above), and async mode interactive / dedicated.
Most other values - including the line password, the login command, flow control, speed, modem inout, and transport input - are configured on the line level.
164(config)#line 2
164(config-line)#login
164(config-line)#password CCNP
164(config-line)#flowcontrol hardware
164(config-line)#speed 56000
164(config-line)#modem inout
164(config-line)#transport input all
164(config-line)#stopbits 1
A good way to remember which commands go on the line and which go on the async interface - if the command deals with a physical value such as speed, stopbits, etc., the command should go on the line. If the command deals with a logical value - IP address, for example - the value should be assigned to the logical interface.
To your success,
Chris Bryant
CCIE #12933
chris@thebryantadvantage.com
|
