PART III
Configuring a Router
Chapter 6 Configuring a Single Cisco Router
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CHAPTER 6
Configuring a Single
Cisco Router
This chapter provides information and commands concerning the following topics:
• Router modes
• Entering global configuration mode
• Configuring a router, specifically
— Names
— Passwords
— Password encryption
— Interface names
— Moving between interfaces
— Configuring a serial interface
— Configuring a Fast Ethernet interface
— Creating a message-of-the-day (MOTD) banner
— Creating a login banner
— Setting the clock time zone
— Assigning a local host name to an IP address
— The no ip domain-lookup command
— The logging synchronous command
— The exec-timeout command
— Saving configurations
— Erasing configurations
• show commands to verify the router configurations
• EXEC commands in configuration mode: the do command
Router Modes
Router>

cc
oo
oo
nn
nn
ff
ff
ii
ii
gg
gg
uu
uu
rr
rr
ee
eett
tt
ee
ee
rr
rr
mm
mm
ii
ii
nn

ii
ss
ss
cc
cc
oo
oo
The name can be any word you
choose.
Cisco(config)#
Router(config)#
ee
ee
nn
nn
aa
aa
bb
bb
ll
ll
ee
eepp
pp
aa
aa
ss

bb
bb
ll
ll
ee
eess
ss
ee
ee
cc
cc
rr
rr
ee
ee
tt
ttcc
cc
ll
ll
aa
aa
ss
ss

oo
ll
ll
ee
ee00
00
Enters console line mode
Router(config-line)#pp
pp
aa
aa
ss
ss
ss
ss
ww
ww
oo
oo
rr
rr
dd
ddcc
cc

nn
ee
eevv
vv
tt
tt
yy
yy00
0044
44
Enters vty line mode for all five vty
lines
Router(config-line)#pp
pp
aa
aa
ss
ss
ss
ss
ww

nn
nn
Enables password checking at login
Router(config)#ll
ll
ii
ii
nn
nn
ee
eeaa
aa
uu
uu
xx
xx00
00
Enters auxiliary line mode
Router(config-line)#pp
pp
aa
aa
ss
ss

Router(config-line)#ll
ll
oo
oo
gg
gg
ii
ii
nn
nn
Enables password checking at login
Router(config)#ss
ss
ee
ee
rr
rr
vv
vv
ii
ii
cc
cc
ee
eepp
pp
aa

ii
o
o
oo
nn
nn
Applies a weak encryption to
passwords
Router(config)#ee
ee
nn
nn
aa
aa
bb
bb
ll
ll
ee
eepp
pp
aa
aa
ss
ss
ss
ss


cc
cc
oo
oo
nn
nn
ss
ss
oo
oo
ll
ll
ee
ee00
00
Moves to console line mode
Router(config-line)#pp
pp
aa
aa
ss
ss
ss
ss
ww
ww

rr
rr
vv
vv
ii
ii
cc
cc
ee
eepp
pp
aa
aa
ss
ss
ss
ss
ww
ww
oo
oo
rr
rr
dd
dd
--
--

The following chart is a sample of some of the different interface names for various routers.
This is by no means a complete list. Refer to the hardware guide of the specific router
that you are working on to see the different combinations, or use the following command
to see which interfaces are installed on your particular router:
router#ss
ss
hh
hh
oo
oo
ww
wwii
ii
pp
ppii
ii
nn
nn
tt
tt
ee
ee
rr
rr

2514 On board Ethernet Interface-type number e0 & e1
On board Serial Interface-type number s0 & s1
1721 On board Fast Ethernet Interface-type number fastethernet0
(fa0)
Slot 0 WAC (WIN
interface card)
(serial)
Interface-type number s0 & s1
1760 On Board Fast Ethernet Interface-type 0/port fa0/0
Slot 0 WIC/VIC (voice
interface card)
Interface-type 0/port s0/0 & s0/1
v0/0 & v0/1
Slot 1 WIC/VIC Interface-type 1/port s1/0 & s1/1
v1/0 & v1/1