Semester 2 v3'1'1: Routers and Routing Basics

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Semester 2 v3.1.1Routers and Routing Basics

• MODULE 3
• Configuring a Router

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IOS EXEC and Config Modes
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Initial Router Configuration

• To alter a routers configuration, enter global
  config mode.
• Router configure terminal
• Router(config) exit (or hit CTRLZ)
• Router
• First task should be to uniquely name the
  router...
• Router(config) hostname Sydney
• Sydney(config)
• ... then restrict router access with password
  security.
• Restrict router session access via all lines, eg.
  virtual terminal
• Enhance password security with service
  password-encryption
• Router(config) service password-encryption
• Router(config) line vty 0 4
• Router(config-line) password guessmeifyoucan
• Router(config-line) login
• Router(config-line) logging synchronous
• Restrict ability to alter router configuration by
  passwording access to Privileged EXEC mode,
  preferably using enable secret to make an
  encrypted password.

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Halt! Who goes there?
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Time for Show and Tell!

• show commands display various aspects of the
  current router configuration.
• show running-config Displays the contents of the
  currently running configuration file.
• show running-config interface fastethernet 0/1
  Displays current configuration of specified
  interface.
• show startup-config Displays the saved
  configuration located in NVRAM.
• show interfaces Statistics for all router
  interfaces.
• show interfaces fastethernet 0/1 Displays
  statistics for the specific interface on that
  slot/port number.
• show ip interfaces brief Shows configured IP
  information and status for all router interfaces.
• show protocols Displays the global and
  interface-specific status of any configured Layer
  3 protocols.
• show arp Displays the ARP table of the router.

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Configuring an Interface

• Interfaces are configured in interface config
  mode, accessed via global config mode.
• Sydney configure terminal
• Sydney(config) interface serial 0/1
• Sydney(config-if)
• Once an interface has been selected, specify a
  network address and subnet mask.
• Sydney(config-if) ip address 10.0.4.1
  255.192.0.0
• If the interface is a serial interface and is to
  be a DCE device, provide a clocking signal.
• Sydney(config-if) clock rate 64000
• Lastly, administratively enable the interface.
• Sydney(config-if) no shutdown

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Saving Configuration Changes
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Please Explain?

• Add descriptions and information where possible
  to help router usage and administration.
• Interface Descriptions should provide clear and
  specific information about the interface, eg.
  what department, building it services.
• Login Banners can be seen by anyone who attempts
  to login to a router.
• Should warn off unauthorised users!
• Can be used to inform users of router downtime.

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Resolving Host Names

• Devices can use host names instead of IP
  addresses, provided a host table is configured.
• A host table associates host names with IP
  addresses
• Host names, unlike DNS names, are significant
  only on the device on which they are configured.

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Get Backed Up

• Just as with servers, router files can be backed
  up for security and recovery purposes.
• Config files can be backed up to a network
  server, TFTP server, or to disk.

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Welcome to my world )

• Daniel Comarmond
• CCNP, CCDP, CCSP, CCAI
• Cisco Networking Academy Instructor
• Systems Engineer Cisco Systems
• E-Mail dcom_at_it.uts.edu.au
• MSN dcom82_at_dcom82.com
• Phone [phone]
• Website http//www-staff.it.uts.edu.au/dcom
• Take care, and SMILE!!! )