Example: Configuring Independent Micro BFD Sessions for LAG

Requirements

• MX Series routers with Junos Trio chipset
• T Series routers with Type 4 FPC or Type 5 FPC

  BFD for LAG is supported on the following PIC types on T-Series:

  • PC-1XGE-XENPAK (Type 3 FPC),
  • PD-4XGE-XFP (Type 4 FPC),
  • PD-5-10XGE-SFPP (Type 4 FPC),
  • 24x10GE (LAN/WAN) SFPP, 12x10GE (LAN/WAN) SFPP, 1X100GE Type 5 PICs
• PTX Series routers with 24X10GE (LAN/WAN) SFPP
• Junos OS Release 13.3 or later running on all devices

Overview

The example includes two routers that are directly connected. Configure two aggregated Ethernet interfaces, AE0 for IPv4 connectivity and AE1 for IPv6 connectivity..Configure micro BFD session on the AE0 bundle using IPv4 addresses as local and neighbor endpoints on both routers.Configure micro BFD session on the AE1 bundle using IPv6 addresses as local and neighbor endpoints on both routers. This example verifies that independent micro BFD sessions are active in the output.

Topology

Figure 1 shows the sample topology.

Figure 1: Configuring an Independent Micro BFD Session for LAG

Configuration

CLI Quick Configuration

To quickly configure this example, copy the following commands, paste them into a text file, remove any line breaks, change any details necessary to match your network configuration, and then copy and paste the commands into the CLI at the [edit] hierarchy level.

Configuring a Micro BFD Session for Aggregated Ethernet Interfaces

Step-by-Step Procedure

The following example requires that you navigate various levels in the configuration hierarchy. For information about navigating the CLI, see “Using the CLI Editor in Configuration Mode” in the CLI User Guide.

Note: Repeat this procedure for Router R1, modifying the appropriate interface names, addresses, and any other parameters for each router.

To configure a micro BFD session for aggregated Ethernet interfaces on Router R0:

1. Configure the physical interfaces.
   [edit interfaces]user@R0# set ge-1/0/1 unit 0 family inet address 20.20.20.1/30user@R0# set ge-1/0/1 unit 0 family inet6 address 3ffe::1:1/126user@R0# set xe-4/0/0 gigether-options 802.3ad ae0user@R0# set xe-4/0/1 gigether-options 802.3ad ae0user@R0# set xe-4/1/0 gigether-options 802.3ad ae1user@R0# set xe-4/1/1 gigether-options 802.3ad ae1
2. Configure the loopback interface.
   [edit interfaces]user@R0# set lo0 unit 0 family inet address 10.255.106.107/32user@R0# set lo0 unit 0 family inet6 address 201:DB8:251::aa:aa:1/128
3. Configure an IP address on the aggregated Ethernet interface ae0 with either IPv4 or IPv6 addresses, as per your network requirements.
   [edit interfaces]user@R0# set ae0 unit 0 family inet address 10.0.0.1/30
4. Set the routing option, create a static route, and set the next-hop address.

   Note: You can configure either an IPv4 or IPv6 static route, depending on your network requirements.

   [edit routing-options]user@R0# set nonstop-routinguser@R0# set static route 30.30.30.0/30 next-hop 10.0.0.2user@R0# set rib inet6.0 static route 3ffe::1:2/126 next-hop 5555::2
5. Configure the Link Aggregation Control Protocol (LACP).
   [edit interfaces]user@R0# set ae0 aggregated-ether-options lacp active
6. Configure BFD for the aggregated Ethernet interface ae0, and specify the minimum interval, local IP address, and the neighbor IP address.
   [edit interfaces]user@R0# set ae0 aggregated-ether-options bfd-liveness-detection minimum-interval 100user@R0# set ae0 aggregated-ether-options bfd-liveness-detection multiplier 3user@R0# set ae0 aggregated-ether-options bfd-liveness-detection neighbor 10.255.106.102user@R0# set ae0 aggregated-ether-options bfd-liveness-detection local-address 10.255.106.107user@R0# set ae0 aggregated-ether-options minimum-links 1user@R0# set ae0 aggregated-ether-options link-speed 10g
7. Configure an IP addresse on the aggregated Ethernet interface ae1.

   You can assign either IPv4 or IPv6 addresses as per your network requirements.

   [edit interfaces]user@R0# set ae1 unit 0 family inet6 address 5555::1/126
8. Configure BFD for the aggregated Ethernet interface ae1.
   [edit interfaces]user@R0# set ae1 aggregated-ether-options bfd-liveness-detection minimum-interval 100user@R0# set ae1 aggregated-ether-options bfd-liveness-detection multiplier 3user@R0# set ae1 aggregated-ether-options bfd-liveness-detection neighbor 201:DB8:251::bb:bb:1user@R0# set ae1 aggregated-ether-options bfd-liveness-detection local-address 201:DB8:251::aa:aa:1user@R0# set ae1 aggregated-ether-options minimum-links 1user@R0# set ae1 aggregated-ether-options link-speed 10g

   Note: Beginning with Junos OS Release 16.1, you can also configure this feature with the AE interface address as the local address in a micro BFD session.

9. Configure tracing options for BFD for troubleshooting.
   [edit protocols]user@R0# set bfd traceoptions file bfduser@R0# set bfd traceoptions file size 100muser@R0# set bfd traceoptions file files 10user@R0# set bfd traceoptions flag all

Results

Verification

Confirm that the configuration is working properly.

• Verifying That the Independent BFD Sessions Are Up
• Viewing Detailed BFD Events

Verifying That the Independent BFD Sessions Are Up

Purpose

Verify that the micro BFD sessions are up, and view details about the BFD sessions.

Action

                                                  Detect   Transmit
Address                  State     Interface      Time     Interval  Multiplier
10.255.106.102                 Up        xe-4/0/0       9.000     3.000        3   
 Client LACPD, TX interval 0.100, RX interval 0.100
 Session up time 4d 23:13, previous down time 00:00:06
 Local diagnostic None, remote diagnostic None
 Remote heard, hears us, version 1
 Replicated 
 Session type: Micro BFD
 Min async interval 0.100, min slow interval 1.000
 Adaptive async TX interval 0.100, RX interval 0.100
 Local min TX interval 0.100, minimum RX interval 0.100, multiplier 3
 Remote min TX interval 3.000, min RX interval 3.000, multiplier 3
 Local discriminator 21, remote discriminator 75
 Echo mode disabled/inactive
 Remote is control-plane independent
  Session ID: 0x0

                                                  Detect   Transmit
Address                  State     Interface      Time     Interval  Multiplier
10.255.106.102                 Up        xe-4/0/1       9.000     3.000        3   
 Client LACPD, TX interval 0.100, RX interval 0.100
 Session up time 4d 23:13, previous down time 00:00:07
 Local diagnostic None, remote diagnostic None
 Remote heard, hears us, version 1
 Replicated 
 Session type: Micro BFD
 Min async interval 0.100, min slow interval 1.000
 Adaptive async TX interval 0.100, RX interval 0.100
 Local min TX interval 0.100, minimum RX interval 0.100, multiplier 3
 Remote min TX interval 3.000, min RX interval 3.000, multiplier 3
 Local discriminator 19, remote discriminator 74
 Echo mode disabled/inactive
 Remote is control-plane independent
  Session ID: 0x0

                                                  Detect   Transmit
Address                  State     Interface      Time     Interval  Multiplier
201:DB8:251::bb:bb:1                  Up        xe-4/1/1       9.000     3.000        3   
 Client LACPD, TX interval 0.100, RX interval 0.100
 Session up time 4d 23:13
 Local diagnostic None, remote diagnostic None
 Remote not heard, hears us, version 1
 Replicated 
 Session type: Micro BFD
 Min async interval 0.100, min slow interval 1.000
 Adaptive async TX interval 0.100, RX interval 0.100
 Local min TX interval 1.000, minimum RX interval 0.100, multiplier 3
 Remote min TX interval 3.000, min RX interval 3.000, multiplier 3
 Local discriminator 17, remote discriminator 67
 Echo mode disabled/inactive, no-absorb, no-refresh
 Remote is control-plane independent
  Session ID: 0x0

                                                  Detect   Transmit
Address                  State     Interface      Time     Interval  Multiplier
201:DB8:251::bb:bb:1                  UP        xe-4/1/0       9.000     3.000        3   
 Client LACPD, TX interval 0.100, RX interval 0.100
 Session up time 4d 23:13
 Local diagnostic None, remote diagnostic None
 Remote not heard, hears us, version 1
 Replicated 
 Session type: Micro BFD
 Min async interval 0.100, min slow interval 1.000
 Adaptive async TX interval 0.100, RX interval 0.100
 Local min TX interval 1.000, minimum RX interval 0.100, multiplier 3
 Remote min TX interval 3.000, min RX interval 3.000, multiplier 3
 Local discriminator 16, remote discriminator 66
 Echo mode disabled/inactive, no-absorb, no-refresh
 Remote is control-plane independent
  Session ID: 0x0

4 sessions, 4 clients
Cumulative transmit rate 2.0 pps, cumulative receive rate 1.7 pps

Meaning

The Micro BFD field represents the independent micro BFD sessions running on the links in a LAG. The TX interval item, RX interval item output represents the setting configured with the minimum-interval statement. All of the other output represents the default settings for BFD. To modify the default settings, include the optional statements under bfd-liveness-detection statement.

Viewing Detailed BFD Events

Purpose

View the contents of the BFD trace file to assist in troubleshooting, if required.

Action

From operational mode, enter the file show /var/log/bfd command.

Jun  5 00:48:59    Protocol (1) len 1: BFD
Jun  5 00:48:59    Data (9) len 41: (hex) 42 46 44 20 6e 65 69 67 68 62 6f 72 20 31 30 2e 30 2e 30
Jun  5 00:48:59 PPM Trace: BFD neighbor 10.255.106.102 (IFL 349) set, 9 0
Jun  5 00:48:59 Received Downstream RcvPkt (19) len 108:
Jun  5 00:48:59    IfIndex (3) len 4: 329
Jun  5 00:48:59    Protocol (1) len 1: BFD
Jun  5 00:48:59    SrcAddr (5) len 8: 10.255.106.102
Jun  5 00:48:59    Data (9) len 24: (hex) 00 88 03 18 00 00 00 4b 00 00 00 15 00 2d c6 c0 00 2d c6
Jun  5 00:48:59    PktError (26) len 4: 0
Jun  5 00:48:59    RtblIdx (24) len 4: 0
Jun  5 00:48:59    MultiHop (64) len 1: (hex) 00
Jun  5 00:48:59    Unknown (168) len 1: (hex) 01
Jun  5 00:48:59    Unknown (171) len 2: (hex) 02 3d
Jun  5 00:48:59    Unknown (172) len 6: (hex) 80 71 1f c7 81 c0
Jun  5 00:48:59    Authenticated (121) len 1: (hex) 01
Jun  5 00:48:59 BFD packet from 10.0.0.2 (IFL 329), len 24
Jun  5 00:48:59    Ver 0, diag 0, mult 3, len 24
Jun  5 00:48:59    Flags: IHU Fate
Jun  5 00:48:59    My discr 0x0000004b, your discr 0x00000015
Jun  5 00:48:59    Tx ivl 3000000, rx ivl 3000000, echo rx ivl 0
Jun  5 00:48:59 [THROTTLE]bfdd_rate_limit_can_accept_pkt: session 10.255.106.102 is up or already in program thread
Jun  5 00:48:59 Replicate: marked session (discr 21) for update
 

Meaning

BFD messages are being written to the specified trace file.