The router connected to a traffic source encapsulates the multicast data into unicast packets and sends them to the rendezvous point (RP) for the domain in a PIM Register Message. The rendezvous point (RP) which receives this Register message must have the capability of de-encapsulating tunneled packets from the multicast source.
In older Juniper platforms, a special Tunnel PIC was required to perform this function. MX Series routers do not support Tunnel Services PICs. To facilitate tunnel encapsulation/decapsulation scenarios like the Multicast, GRE etc., MX series routers provide the ability to create virtual tunnel interfaces using the PFE bandwidth of a FPC in the system. When using the DPC line cards for using tunnel services, it is required that a single 10G port be disabled.
However, with Trio-based line cards, the tunnel services are built into each PFE and there’s no need to disable a port to allow the tunnel services. Since the tunnel service processing happens directly on the line card, the performance is near line-rate and keeps the latency to a minimum.
The following are some of the tunnel interfaces created in MX platforms, when tunnel services are enabled.
IP Tunnel (IPIP) IPIP is a very basic IP tunneling protocol that simply encapsulates the original packet in a new IP header. The interface name for IPIP in Junos is “ip-.”
Generic Routing Encapsulation (GRE) GRE improves upon IPIP and adds the ability to enforce packet sequencing, specify tunnel keys, and encapsulation any Layer 3 protocol without being limited to only IP. The interface name for GRE in Junos is “gr-.”
Logical Tunnels Logical tunnels are pseudo-interfaces in Junos; they look and feel like regular interfaces, but don’t consume any physical ports. A common use case is to use a logical tunnel to interconnect two VRFs. The interface name for logical tunnels in Junos is “lt-.”
Protocol Independent Multicast (PIM) Encapsulation and Decapsulation These interfaces are used by PIM designated routers (DR) or rendezvous points (RP) to encapsulate and decapsulate packets during the PIM JOIN and REGISTER processes. The interface names for PIM encapsulation and decapsulation in Junos are “pe-” and “pd-.” For MPC s and MICs, this bandwidth is not reserved for tunnel traffic and can be shared by the network interfaces. For DPCs, this bandwidth is reserved and cannot be shared by the network interfaces.
In MX Series router, as seen above, it is the pe and pd interface which facilitates the tunneling of encapsulated Register message from the First Hop Router (FHR - Router connected to Source) to the Rendezvous point (RP) router. The FHR will use the pe (PIM encapsulation) interface while the RP will use the pd (PIM decapsulation) interface.
The bandwidth that is specified determines the port number of the tunnel interfaces that will be created. When we specify a bandwidth of 1g, the port number is always 10. When we specify any other bandwidth, the port number is always 0.
labroot@123> show configuration chassis Oct 01 15:40:30 redundancy { graceful-switchover; } aggregated-devices { ethernet { device-count 100; } } network-services enhanced-ip; [MASTER] labroot@123> show interfaces terse | match -4/3 Oct 01 15:40:48 lc-4/3/0 up up lc-4/3/0.32769 up up vpls pfe-4/3/0 up up pfe-4/3/0.16383 up up inet xe-4/3/0 up down xe-4/3/1 up down xe-4/3/2 up down xe-4/3/3 up down <-- No Virtual Interfaces in 4/3 slot [MASTER] labroot@123> show chassis fpc pic-status Oct 01 15:41:12 Slot 1 Online MPC5E 3D 2CGE+4XGE PIC 0 Online 2X10GE SFPP OTN PIC 1 Online 1X100GE CFP2 OTN PIC 2 Online 2X10GE SFPP OTN PIC 3 Online 1X100GE CFP2 OTN Slot 3 Online MPC2E NG PQ & Flex Q PIC 0 Online 2x 10GE XFP PIC 1 Online 2x 10GE XFP PIC 2 Online 10x 1GE(LAN) SFP PIC 3 Online 10x 1GE(LAN) SFP Slot 4 Online MPC 3D 16x 10GE PIC 0 Online 4x 10GE(LAN) SFP+ PIC 1 Online 4x 10GE(LAN) SFP+ PIC 2 Online 4x 10GE(LAN) SFP+ PIC 3 Online 4x 10GE(LAN) SFP+ <-- Will use this pic for 1g tunnel bandwidth in this example Slot 5 Online MPC5E 3D Q 2CGE+4XGE PIC 0 Online 2X10GE SFPP OTN PIC 1 Online 1X100GE CFP2 OTN PIC 2 Online 2X10GE SFPP OTN PIC 3 Online 1X100GE CFP2 OTN [master] labroot@123> configure Oct 01 15:41:14 Entering configuration mode [master][edit] labroot@123# set chassis fpc 4 pic 3 tunnel-services bandwidth 1g Oct 01 15:41:31 [master][edit] labroot@123# commit Oct 01 15:41:34 re1: configuration check succeeds re0: commit complete re1: commit complete [master][edit] labroot@123# exit Oct 01 15:41:41 Exiting configuration mode [master] labroot@123> show configuration chassis Oct 01 15:41:44 redundancy { graceful-switchover; } aggregated-devices { ethernet { device-count 100; } } fpc 4 { pic 3 { tunnel-services { bandwidth 1g; } } } network-services enhanced-ip; [master] labroot@123> show interfaces terse | match -4/3 Oct 01 15:41:49 lc-4/3/0 up up lc-4/3/0.32769 up up vpls pfe-4/3/0 up up pfe-4/3/0.16383 up up inet xe-4/3/0 up down xe-4/3/1 up down xe-4/3/2 up down xe-4/3/3 up down gr-4/3/10 up up ip-4/3/10 up up lt-4/3/10 up up mt-4/3/10 up up pd-4/3/10 up up pe-4/3/10 up up pe-4/3/10.32769 up up inet <-- For PIM Encapsulation ud-4/3/10 up up ut-4/3/10 up up vt-4/3/10 up up vt-4/3/10.2097666 up up inet <-- A set of virtual ports are created - Note the 4/3/10 [master] labroot@123> show interfaces pe-4/3/10.32769 <-- PIM Encapsulated virtual interface connecting to RP Oct 01 15:42:02 Logical interface pe-4/3/10.32769 (Index 344) (SNMP ifIndex 696) Flags: Up Point-To-Point SNMP-Traps 0x4000 IP-Header 4.4.4.4:2.2.2.2:103:df:64:2100deff00000000 Encapsulation: PIM-NULL Input packets : 0 Output packets: 0 Protocol inet, MTU: 1472 Max nh cache: 0, New hold nh limit: 0, Curr nh cnt: 0, Curr new hold cnt: 0, NH drop cnt: 0 Flags: None [master] labroot@123>
labroot@123> show configuration chassis Oct 01 15:43:14 redundancy { graceful-switchover; } aggregated-devices { ethernet { device-count 100; } } network-services enhanced-ip; [master] labroot@123> show chassis fpc pic-status Oct 01 15:43:19 Slot 1 Online MPC5E 3D 2CGE+4XGE PIC 0 Online 2X10GE SFPP OTN PIC 1 Online 1X100GE CFP2 OTN PIC 2 Online 2X10GE SFPP OTN PIC 3 Online 1X100GE CFP2 OTN Slot 3 Online MPC2E NG PQ & Flex Q PIC 0 Online 2x 10GE XFP PIC 1 Online 2x 10GE XFP PIC 2 Online 10x 1GE(LAN) SFP PIC 3 Online 10x 1GE(LAN) SFP Slot 4 Online MPC 3D 16x 10GE PIC 0 Online 4x 10GE(LAN) SFP+ PIC 1 Online 4x 10GE(LAN) SFP+ PIC 2 Online 4x 10GE(LAN) SFP+ PIC 3 Online 4x 10GE(LAN) SFP+ <-- Will use 10g bandwidth from this PIC Slot 5 Online MPC5E 3D Q 2CGE+4XGE PIC 0 Online 2X10GE SFPP OTN PIC 1 Online 1X100GE CFP2 OTN PIC 2 Online 2X10GE SFPP OTN PIC 3 Online 1X100GE CFP2 OTN [master] labroot@123> show interfaces terse | match -4/3 Oct 01 15:43:23 lc-4/3/0 up up lc-4/3/0.32769 up up vpls pfe-4/3/0 up up pfe-4/3/0.16383 up up inet xe-4/3/0 up down xe-4/3/1 up down xe-4/3/2 up down xe-4/3/3 up down [master] labroot@123> configure Oct 01 15:43:28 Entering configuration mode [master][edit] labroot@123# set chassis fpc 4 pic 3 tunnel-services bandwidth 10g Oct 01 15:43:33 [master][edit] labroot@123# commit Oct 01 15:43:35 re1: configuration check succeeds re0: commit complete re1: commit complete [master][edit] labroot@123# exit Oct 01 15:43:42 Exiting configuration mode [master] labroot@123> show configuration chassis Oct 01 15:43:44 redundancy { graceful-switchover; } aggregated-devices { ethernet { device-count 100; } } fpc 4 { pic 3 { tunnel-services { bandwidth 10g; } } } network-services enhanced-ip; [master] labroot@123> show chassis fpc pic-status Oct 01 15:43:46 Slot 1 Online MPC5E 3D 2CGE+4XGE PIC 0 Online 2X10GE SFPP OTN PIC 1 Online 1X100GE CFP2 OTN PIC 2 Online 2X10GE SFPP OTN PIC 3 Online 1X100GE CFP2 OTN Slot 3 Online MPC2E NG PQ & Flex Q PIC 0 Online 2x 10GE XFP PIC 1 Online 2x 10GE XFP PIC 2 Online 10x 1GE(LAN) SFP PIC 3 Online 10x 1GE(LAN) SFP Slot 4 Online MPC 3D 16x 10GE PIC 0 Online 4x 10GE(LAN) SFP+ PIC 1 Online 4x 10GE(LAN) SFP+ PIC 2 Online 4x 10GE(LAN) SFP+ PIC 3 Online 4x 10GE(LAN) SFP+ Slot 5 Online MPC5E 3D Q 2CGE+4XGE PIC 0 Online 2X10GE SFPP OTN PIC 1 Online 1X100GE CFP2 OTN PIC 2 Online 2X10GE SFPP OTN PIC 3 Online 1X100GE CFP2 OTN [master] labroot@123> show interfaces terse | match -4/3 Oct 01 15:43:49 gr-4/3/0 up up ip-4/3/0 up up lc-4/3/0 up up lc-4/3/0.32769 up up vpls lt-4/3/0 up up mt-4/3/0 up up pd-4/3/0 up up pe-4/3/0 up up pe-4/3/0.32769 up up inet <-- PIM encapsulation interface to send Register to RE pfe-4/3/0 up up pfe-4/3/0.16383 up up inet ud-4/3/0 up up ut-4/3/0 up up vt-4/3/0 up up vt-4/3/0.2097667 up up inet <-- A set of virtual ports created - Note the 4/3/0 for 10g bandwidth xe-4/3/0 up down xe-4/3/1 up down xe-4/3/2 up down xe-4/3/3 up down [master] labroot@123> show interfaces pe-4/3/0.32769 Oct 01 15:44:05 Logical interface pe-4/3/0.32769 (Index 344) (SNMP ifIndex 698) Flags: Up Point-To-Point SNMP-Traps 0x4000 IP-Header 4.4.4.4:2.2.2.2:103:df:64:2100deff00000000 Encapsulation: PIM-NULL Input packets : 0 Output packets: 0 Protocol inet, MTU: 1472 Max nh cache: 0, New hold nh limit: 0, Curr nh cnt: 0, Curr new hold cnt: 0, NH drop cnt: 0 Flags: None [master] labroot@123>
12/9/2024 dconejomora - adding MX480 to the case categories