Friday, March 26, 2010

Configuring Virtual Routers

There are different uses of the virtual-router command. You can create or access VRs and VRFs in Global Configuration mode or map a VR to a domain map in Domain Map Configuration mode. Once you create a VR, you can continue to work in different command modes and configure the same user interface parameters as before the virtual router was created.


Create and name a VR in Configuration mode.
host1(config)#virtual-router western
  • reate a VRF to provide forwarding information to your router. In this example, the VRF created is in context with the VR created above.
  • host1:western(config)#ip vrf eastern
    Proceed with new VRF creation? [confirm]
    host1:western(config-vrf)#virtual-router:eastern
    host1:western:eastern(config)#

  • Access a VRF from th


    e context of a different VR.
  • host1(config)#virtual-router western:eastern
ew your configuration choices from a VR or VRF context.

host1:western:eastern(config)#?
  aaa                      Configure authentication, authorization,
                           and accounting characteristics
  access-list              Configure an access list entry
  arp                      Configure a static ARP entry
  bandwidth                Configure slot-group bandwidth control
  banner                   Define a banner line
  baseline                 Configure baseline operations
  boot                     Configure boot time behavior
  bulkstats                Configure bulkstats parameters
  cbf                      Configure connection-based forwarding
  classifier-list          Configure a classifier list entry
  clns                     Configure CLNS characteristics
  clock                    Set the system's clock
  controller               Configure controller parameters
  crypto                   Configure cryptographic parameters
  disable-autosync         Disable automatic synchronization of
                           redundant system controller file system
  disable-switch-on-error  Disable automatic switch to redundant system
                           controller upon software/hardware error
  enable                   Configure security related options
  end                      Exit Global Configuration mode
  exception                Configure core dump
  exclude-subsystem        Exclude copying a subsystem from the release
  exit                     Exit from the current command mode
  ftp-server               Configure FTP Server characteristics
  help                     Describe the interactive help system
  host                     Add/modify an entry to the host table
  hostname                 Set the host (system) name
  interface                Enter Interface Configuration mode
  ip                       Configure IP characteristics
  l2tp                     Configure L2TP parameters
  license                  Configure licenses
  line                     Enter Line Configuration mode
  log                      Configure logging settings
  macro                    Run a CLI macro
  map-list                 Create an NBMA static map
  memory                   Configure and administer memory operations
  mpls                     Configure MPLS global parameters
  no                       Negate a command or set its default(s)
  ntp                      Configure the Network Time Protocol
  policy-list              Enter Policy Configuration mode
  pppoe                    Configure PPPoE
  profile                  Specify a profile
  radius                   Configure RADIUS server
  rate-limit-profile       Enter rate limit profile configuration mode
  redundancy               Perform a redundancy configuration
  route-map                Configure a route map
  router                   Configure a routing protocol
  rtr                      Configure rtr parameters
  service                  Configure system-level services
  set                      Configure
  sleep                    Make the Command Interface pause for a
                           specified duration
  slot                     Configure and administer slot operation
  snmp-server              Configure SNMP parameters
  sscc                     The SSC Client
  telnet                   telnet daemon configuration
  timing                   Configure network timing
  traffic-shape-profile    Enter traffic shape profile configuration mode
  virtual-router           Specify a virtual router
host1:western:eastern(config)#

  • View the VRF configuration choices from VRF Configuration mode.
  • host1:western(config-vrf)#?
      exit          Exit from the current command mode
      export        Specify VRF export characteristics
      help          Describe the interactive help system
      import        Specify VRF import characteristics
      log           Configure logging settings
      macro         Run a CLI macro
      no            Negate a command or set its default(s)
      rd            Specify route distinguisher
      route-target  Specify VPN extended community Target
      sleep         Make the Command Interface pause for a
                     specified duration
    host1:western(config-vrf)#

  • Access a VR to configure it with an interior gateway protocol (IGP) or exterior gateway protocol (EGP) to learn routes from a customer edge device (CE). See the related routing protocol chapters for detailed information.

Example 1
VR with an IGP

host1(config)#virtual-router miami
host1:miami(config)#router ospf 5
host1:miami(config-router)#

Example 2
VR with an EGP

host1(config)#virtual-router western
host1:western(config)#router bgp 359
host1:western(config-router)#

  • Configure a Telnet daemon to listen in VRs other than the default VR.
  • host1(config)#virtual-router boston
    host1:boston(config)#telnet listen port 23

  • List all VRs and VRFs on the router.
  • host1#show virtual-router
    Virtual Router : default
    Virtual Router : thursday
    Virtual Router : western
                     VRF : eastern
    Virtual Router : boston
    Virtual Router : miami
    Virtual Router : northern
                     VRF : southern
    host1#

  • Map a VR to a user domain name in Domain Map Configuration mode. The VR must already exist.
  • host1(config)#aaa domain-map jacksonville
    host1(config-domain-map)#virtual-router western
    host1(config-domain-map)#

aaa domain-map

  • Use to map a user domain name to a virtual router.
  • Examples
  • host1-0-1-90(config)#aaa domain-map juniper.net vrouter_1
    host1-0-1-90(config)#aaa domain-map none vrouter__all_purpose
    host1-0-1-90(config)#aaa domain-map DEFAULT vrouter_all_purpose

  • Use the no version of the command to delete the domain map.

ip vrf

  • Use to create a VRF or access VRF Configuration mode to configure a VRF.
  • You must specify a route distinguisher after you create a VRF. Otherwise, the VRF will not operate.
  • Example
  • host1-00-02-80:boston(config)#ip vrf vpn-A

  • Use the no version to remove a VRF.

telnet listen

  • Use to create a Telnet daemon to listen in a virtual router.
  • Example
  • host1(config)#virtual-router 3
    host1:3(config)#telnet listen port 3223

  • Use the no version of the command to delete the daemon.

virtual-router

  • From Global Configuration mode, use this command to create a virtual router or access the context of a previously created virtual router or a VRF.
  • From Domain Map Configuration mode, use this command to map the VR to a user domain name. Use the no version in this mode to delete the VR parameter and assign the default VR.
  • A VR name consists of 1-32 alphanumeric characters.
  • Once you are in the context of a particular VR or VRF (indicated by the change in the prompt), all subsequent commands you enter apply to that context until you exit the context.
  • Use the no version of the command only to delete the VR and return the router to the default VR. Issuing the command no virtual-router vrName.vrfName has no effect.
  • Issuing a no version of this command (no virtual-router :vrfName or no virtual-router vrName:vrfName) that specifies an existing VRF only displays the error message: "Cannot delete a VRF with this command." You must use the no ip vrf command to remove a VRF.

    NOTE: See JUNOSe Command Reference Guide for additional information.


  • Use the wait-for-completion keyword with the no version if you require a synchronous, deterministic deletion of a VR, such as when executing Telnet or console commands through an external script. Alternatively, you might want to use this keyword if the VR being deleted has many configured VRFs and someone might attempt to recreate the VR before all the VRFs have been deleted. If you do not issue the wait-for-completion keyword in those circumstances, a virtual-router command issued as soon as the prompt appears could fail because the router is still deleting VRFs. You can specify a period during which the CLI waits before it returns a prompt. If you do not specify a wait time, then the CLI does not return a prompt until the operation completes. You can press Ctrl+c to break out of the wait period early.