Example: Configuring Dynamic Bandwidth Management Using Container LSP

 

This example shows how to enable dynamic bandwidth management by configuring container label-switched paths (LSPs) that enable load balancing across multiple point-to-point member LSPs.

Requirements

This example uses the following hardware and software components:

  • Five routers that can be a combination of M Series, MX Series, or T Series routers, out of which two routers are provider edge (PE) routers and three routers are provider (P) routers

  • Junos OS Release 14.2 or later running on all the routers

Before you begin:

  1. Configure the device interfaces.

  2. Configure the autonomous system numbers and router IDs for the devices.

  3. Configure the following protocols:

    • RSVP

    • MPLS

    • BGP

    • OSPF

Overview

Starting with Junos OS Release 14.2, a new type of LSP, called a container LSP, is introduced to enable load balancing across multiple point-to-point LSPs. A container LSP includes one or more member LSPs between the same ingress and egress routing devices. The member LSPs are similar to independent point-to-point LSPs, and each member LSP takes a different path to the same destination and can be routed along a different IGP cost path.

A container LSP provides support for dynamic bandwidth management by enabling the ingress router to dynamically add and remove member LSPs through a process called LSP splitting and LSP merging, respectively, based on configuration and aggregate traffic. Besides addition and deletion, member LSPs can also be re-optimized with different bandwidth values in a make-before-break way.

Topology

Figure 1 is a sample topology configured with container LSPs.

Figure 1: Dynamic Bandwidth Management Using Container LSP
Dynamic Bandwidth Management Using Container LSP

In this example, Routers PE1 and PE2 are the PE routers connected to hosts Host1 and Host2, respectively. The core routers, Routers P1, and P2, and P3 connect to the PE routers.

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, copy and paste the commands into the CLI at the [edit] hierarchy level, and then enter commit from configuration mode.

PE1

P1

P2

P3

PE2

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.

To configure Router PE1:

  1. Configure the Router PE1 interfaces.
  2. Configure the router ID and autonomous system number for Router PE1.
  3. Enable the policy to load-balance traffic.
  4. Enable RSVP on all Router PE1 interfaces (excluding the management interface).
  5. Enable MPLS on all the interfaces of Router PE1 (excluding the management interface).
  6. Configure the MPLS statistics parameters.
  7. Configure the label-switched path (LSP) template parameters.
  8. Configure a container LSP between Router PE1 and Router PE2, and assign the PE1-to-PE2-template1 LSP template.
  9. Configure the container LSP parameters.
  10. Configure the BGP group, and assign the local and neighbor IP addresses.
  11. Enable OSPF on all the interfaces of Router PE1 (excluding the management interface) along with traffic engineering capabilities.
  12. Configure the policy statement to load-balance traffic.
  13. Configure a routing instance on Router PE1, and assign the routing instance interface.
  14. Configure the route distinguisher, vrf target, and vrf-table label values for the VRF routing instance.

Results

From configuration mode, confirm your configuration by entering the show interfaces, show routing-options, show protocols, show policy-options, and show routing-options commands. If the output does not display the intended configuration, repeat the instructions in this example to correct the configuration.

Verification

Confirm that the configuration is working properly.

Verifying the Container LSP Status Without Bandwidth

Purpose

Verify the status of the container LSP.

Action

From operational mode, run the show mpls container-lsp extensive command.

user@PE1> show mpls container-lsp extensive

Meaning

The container LSP is established between Routers PE1 and PE2.

Verifying the Container LSP Status with Increased Bandwidth (Before Normalization)

Purpose

Verify the status of the container LSP with increased bandwidth before normalization happens.

Action

From operational mode, run the show mpls container-lsp extensive command.

user@PE1> show mpls container-lsp extensive

Meaning

Because normalization has not happened, the member LSP count remains at 2.

Verifying the Container LSP Status with Increased Bandwidth (After Normalization)

Purpose

Verify the status of the container LSP with increased bandwidth after normalization happens.

Action

From operational mode, run the show mpls container-lsp extensive command.

user@PE1> show mpls container-lsp extensive

Meaning

At the expiry of the normalization timer, the container LSP is split into five member LSPs, each with 10 Mbps (minimum and maximum signaling bandwidth). As a result, the aggregate bandwidth is 50 Mbps.

Verifying the Container LSP Splitting Process

Purpose

Verify the container LSP splitting process after normalization happens.

Action

From operational mode, run the show route 2.2.2 command.

user@PE1> show route 2.2.2

Meaning

After LSP splitting, Router PE1 has injected the forwarding adjacency.

Verifying the Container LSP Statistics

Purpose

Verify the container LSP statistics after normalization happens.

Action

From operational mode, run the show mpls container-lsp statistics command.

user@PE1> show mpls container-lsp statistics

Meaning

Traffic is load-balanced across the newly created member LSPs.

Verifying the Container LSP Status with Decreased Bandwidth (Before Normalization)

Purpose

Verify the status of the container LSP with decreased bandwidth before normalization happens.

Action

From operational mode, run the show mpls container-lsp detail command.

user@PE1> show mpls container-lsp detail

Meaning

Because normalization has not happened, the member LSP count remains at 5.

Verifying the Container LSP Status with Decreased Bandwidth (After Normalization)

Purpose

Verify the status of the container LSP with decreased bandwidth after normalization happens.

Action

From operational mode, run the show mpls container-lsp detail command.

user@PE1> show mpls container-lsp detail

Meaning

At the expiry of the normalization timer, the container LSP merging takes place because there is an overall reduction in bandwidth. The member LSPs are merged, and the member LSP count is 2 after normalization.

Verifying the Container LSP Merging Process

Purpose

Verify the container LSP splitting process after normalization happens.

Action

From operational mode, run the show route 2.2.2 command.

user@PE1> show route 2.2.2

Meaning

After LSP merging, Router PE1 has deleted the merged member LSPs.

Verifying Failover Normalization

Purpose

Verify load redistribution when traffic is sent at 35 Mbps and the link between Routers P1 and P2 is disabled. Arrival of PathErr on link failure triggers immediate normalization.

To enable failover normalization, include the failover-normalization configuration statement at the [edit protocols mpls container-label-switched-path container-lsp-name splitting-merging normalization] hierarchy level.

Action

From operational mode, run the show mpls container-lsp command.

user@PE1> show mpls container-lsp

After the ge-0/0/2 link between Routers P1 and P2 goes down, normalization is immediately triggered.

From operational mode, run the show mpls container-lsp detail command.

user@PE1> show mpls container-lsp detail

Meaning

Arrival of PathErr message on link failure triggers immediate normalization.

Verifying Incremental Normalization

Purpose

Verify incremental normalization when enough bandwidth is not available.

On Router PE1, the RSVP interfaces static bandwidth is restricted to 22 Mbps each.

Action

From operational mode, run the show rsvp interface command.

user@PE1> show rsvp interface

Before normalization happens:

From operational mode, run the show mpls container-lsp command.

user@PE1> show mpls container-lsp

After normalization happens:

From operational mode, run the show mpls container-lsp command.

user@PE1> show mpls container-lsp

From operational mode, run the show mpls container-lsp detail command.

user@PE1> show mpls container-lsp detail

Meaning

After normalization, the aggregate bandwidth after three retries is 40.8326 Mbps.