When using LDP for signaling, it is necessary to configure all of the PE and P routers for LDP. It is only necessary to configure the interfaces that fall soley within the service provider network. It is not necessary to enable LDP on the interfaces between the PE and CE. Use the following commands to enable LDP: -
From the configuration mode, type the following to enable LDP: [edit protocols ldp] lab@Chicago# set interface interface name -
MPLS must also be configured on each LDP-configured interface. [edit protocols mpls] lab@Chicago# set interface interface name In order for LDP to function properly, it is necessary to configure either IS-IS or OSPF. More details for enabling IGPs can be found in Chapters 8 and 11. Like RSVP, MPLS needs to be configured on a per-interface basis. The all parameter is also available with MPLS. The following example builds a configuration that will allow an RSVP signaled MPLS LSP. -
From the configuration mode, type the following to enable MPLS. [edit protocols mpls] lab@Chicago# set interface interface name -
In addition to enabling MPLS on each participating interface, it is important to also configure the interface to handle MPLS traffic. [edit interfaces] lab@Chicago# set interfaces interface name unit interface unit number family mpls -
The LSP that is created will be used as a forwarding mechanism for the VPN traffic. [edit protocols mpls] lab@Chicago# set label-switched-path path name to to Note The value for to should be the IP address of the egress router. The path name is a name given as a description for this LSP. When naming items in JUNOS, be as descriptive as possible to make reading the configuration easier later on. This is how the command is displayed in the JUNOS CLI. This configuration statement defines the IP address of the egress router that should be used to set up an LSP dynamically. Use the following show commands to verify the MPLS configuration: -
show mpls lsp ” This command displays the LSPs configured on the router by LSPname , the IP address of the beginning and endpoint of the LSP, the state, and the type of LSP, type being ingress, egress or transit. lab@Chicago# run show mpls lsp Ingress LSP: 1 sessions To From State Rt ActivePath P LSPname 192.168.2.1 192.168.5.1 Up 0 * Chicago-to-newyork Total 1 displayed, Up 1, Down 0 Egress LSP: 1 sessions To From State Rt Style Labelin Labelout LSPname 192.168.5.1 192.168.2.1 Up 0 1 FF 3 - newyork-to-Chicago Total 1 displayed, Up 1, Down 0 Transit LSP: 0 sessions Total 0 displayed, Up 0, Down 0 -
show mpls lsp detail ” This command provides a more in-depth analysis of the LSP. It displays information about the computed route objects, as well as the received route objects. lab@Chicago# run show mpls lsp detail Ingress LSP: 1 sessions 192.168.2.1 From: 192.168.5.1, State: Up, ActiveRoute: 0, LSPname: Chicago-to-newyork ActivePath: (primary) LoadBalance: Random *Primary State: Up Computed ERO (S [L] denotes strict [loose] hops): (CSPF metric: 20) 10.0.0.1 S 10.0.1.1 S Received RRO (S [L] denotes strict [loose] hops): 10.0.0.1 S 10.0.1.1 S Total 1 displayed, Up 1, Down 0 Egress LSP: 1 sessions 192.168.5.1 From: 192.168.2.1, LSPstate: Up, ActiveRoute: 0, LSPname: newyork-to-Chicago Resv style: 1 FF, Label in: 3, Label out: - Time left: 148, Since: Fri Aug 24 14:25:40 2001 Tspec: rate 0bps size 0bps peak Infbps m 20 M 1500 Port number: sender 3 receiver 17 protocol 0 PATH rcvfrom: 10.0.0.1 (at-1/2/1.100) 22 pkts PATH sentto: localclient RESV rcvfrom: localclient Record route: 10.0.1.1 10.0.0.1 <self> Total 1 displayed, Up 1, Down 0 Transit LSP: 0 sessions Total 0 displayed, Up 0, Down 0 Note The output displays both an ingress and egress path. The ingress path is the path that was configured on the other PE router. Each MPLS path is constructed in a unidirectional manner. |