Four Important Commands For Your CCNA / CCNP Home Lab
More CCNA and CCNP candidates than ever before are putting
together their own home practice labs. It's more affordable than
it ever has been, and I receive emails daily from new CCNAs and
CCNPs who say it's the best thing they could have done to
improve their studies.
There are some commands you can configure on your lab routers
that won't necessarily be on your CCNA or CCNP exams, but they
will make life a lot easier for you. Let's take a look at just a
few of these.
The command "no exec" is short, yet powerful. Occasionally
you'll have what is referred to as a "rogue EXEC" process tie up
a line, and you end up having to continually clear lines, which
disrupts your practice. If you have an access server, I highly
recommend you configure this command on your lines, as shown
here:
ACCESS_SERVER(con)#line 1 8
ACCESS_SERVER(con)#no exec
>From your CCNA studies, you know that the command "no ip
domain-lookup" prevents a Cisco router from sending a broadcast
to find a DNS server anytime you enter something that is not an
IOS command - and that includes mistyped commands, which happens
to all of us sooner or later. Make sure to run that command in
global configuration mode on all your practice routers.
There are two commands I like to configure on the console line
on all my practice routers and switches. The first is
"exec-timeout 0 0", which prevents you from being kicked out of
enable mode and back into user exec after a few minutes of
inactivity. (This doesn't sound like much, but you'll get pretty
tired of typing "enable" after a while.) The first zero refers
to minutes, the second zero to seconds. Setting them both to
zero disables the exec-timeout function.
The second command prevents the router from interrupting the
command you're typing with a console message. If you've ever
been in the middle of typing a router command and suddenly
you're interrupted with a logging message, you know that can be
pretty annoying. We don't want the router to not display the
message, but we do want the router to wait until we're done
entering data. The command to perform this is "logging
synchronous".
R1(config)#line console 0
R1(config-line)#exec-timeout 0 0
R1(config-line)#logging synchronous
You won't see many of these commands on your exams, but after
you configure them on your home lab devices, you'll wonder how
you did without them!