Supported Platforms
Configuring Link Protection on Interfaces Used by LSPs
When you configure node protection or link protection on a router for LSPs as described in Configuring Node Protection or Link Protection for LSPs, you also must configure the link-protection statement on the RSVP interfaces used by the LSPs.
To configure link protection on the interfaces used by the LSPs, include the link-protection statement:
You can include this statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name]
All the statements under link-protection are optional.
The following sections describe how to configure link protection:
- Configuring Bypass LSPs
- Configuring Administrative Groups for Bypass LSPs
- Configuring the Bandwidth for Bypass LSPs
- Configuring Class of Service for Bypass LSPs
- Configuring the Hop Limit for Bypass LSPs
- Configuring the Maximum Number of Bypass LSPs
- Disabling CSPF for Bypass LSPs
- Disabling Node Protection for Bypass LSPs
- Configuring the Optimization Interval for Bypass LSPs
- Configuring an Explicit Path for Bypass LSPs
- Configuring the Amount of Bandwidth Subscribed for Bypass LSPs
- Configuring Priority and Preemption for Bypass LSPs
Configuring Bypass LSPs
You can configure specific bandwidth and path constraints for a bypass LSP. You can also individually configure each bypass LSP generated when you enable multiple bypass LSPs. If you do not configure the bypass LSPs individually, they all share the same path and bandwidth constraints (if any).
If you specify the bandwidth, hop-limit, and path statements for the bypass LSP, these values take precedence over the values configured at the [edit protocols rsvp interface interface-name link-protection] hierarchy level. The other attributes (subscription, no-node-protection, and optimize-timer) are inherited from the general constraints.
To configure a bypass LSP, specify a name for the bypass LSP using the bypass statement. The name can be up to 64 characters in length.
You can include this statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection]
Configuring the Next-Hop or Next-Next-Hop Node Address for Bypass LSPs
If you configure a bypass LSP, you must also configure the to statement. The to statement specifies the address for the interface of the immediate next-hop node (for link protection) or the next-next-hop node (for node-link protection). The address specified determines whether this is a link protection bypass or a node-link protection bypass. On multiaccess networks (for example, a LAN), this address is also used to specify which next-hop node is being protected.
Configuring Administrative Groups for Bypass LSPs
Administrative groups, also known as link coloring or resource class, are manually assigned attributes that describe the “color” of links, such that links with the same color conceptually belong to the same class. You can use administrative groups to implement a variety of policy-based LSP setups. You can configure administrative groups for bypass LSPs. For more information about configuring administrative groups, see Configuring Administrative Groups.
To configure administrative groups for bypass LSPs, include the admin-group statement:
To configure an administrative group for all of the bypass LSPs, include the admin-group statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection]
To configure an administrative groups for a specific bypass LSP, include the admin-group statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection bypass bypass-name]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection bypass bypass-name]
Configuring the Bandwidth for Bypass LSPs
You can specify the amount of bandwidth allocated for automatically generated bypass LSPs or you can individually specify the amount of bandwidth allocated for each LSP.
If you have enabled multiple bypass LSPs, this statement is required.
To specify the bandwidth allocation, include the bandwidth statement:
For automatically generated bypass LSPs, include the bandwidth statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection]
For individually configured bypass LSPs, include the bandwidth statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection bypass bypass-name]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection bypass bypass-name]
Configuring Class of Service for Bypass LSPs
You can specify the class-of-service value for bypass LSPs by including the class-of-service statement:
To apply a class-of-service value to all the automatically generated bypass LSPs, include the class-of-service statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection]
To configure a class-of-service value for a specific bypass LSPs, include the class-of-service statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection bypass bypass-name]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection bypass bypass-name]
Configuring the Hop Limit for Bypass LSPs
You can specify the maximum number of hops a bypass can traverse. By default, each bypass can traverse a maximum of 255 hops (the ingress and egress routers count as one hop each, so the minimum hop limit is two).
To configure the hop limit for bypass LSPs, include the hop-limit statement:
For automatically generated bypass LSPs, include the hop-limit statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection]
For individually configured bypass LSPs, include the hop-limit statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection bypass bypass-name]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection bypass bypass-name]
Configuring the Maximum Number of Bypass LSPs
You can specify the maximum number of dynamic bypass LSPs permitted for protecting an interface using the max-bypasses statement at the [edit protocols rsvp interface interface-name link-protection] hierarchy level. When this statement is configured, multiple bypasses for link protection are enabled. Call admission control (CAC) is also enabled.
By default, this option is disabled and only one bypass is enabled for each interface. You can configure a value of between 0 through 99 for the max-bypasses statement. Configuring a value of 0 prevents the creation of any dynamic bypass LSPs for the interface. If you configure a value of 0 for the max-bypasses statement, you need to configure one or more static bypass LSPs to enable link protection on the interface.
If you configure the max-bypasses statement, you must also configure the bandwidth statement (discussed in Configuring the Bandwidth for Bypass LSPs).
To configure the maximum number of bypass LSPs for a protected interface, include the max-bypasses statement:
You can include this statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection]
Disabling CSPF for Bypass LSPs
Under certain circumstances, you might need to disable CSPF computation for bypass LSPs and use the configured Explicit Route Object (ERO) if available. For example, a bypass LSP might need to traverse multiple OSPF areas or IS-IS levels, preventing the CSPF computation from working. To ensure that link and node protection function properly in this case, you have to disable CSPF computation for the bypass LSP.
You can disable CSPF computation for all bypass LSPs or for specific bypass LSPs.
To disable CSPF computation for bypass LSPs, include the no-cspf statement:
For a list of hierarchy levels where you can include this statement, see the statement summary for this statement.
Disabling Node Protection for Bypass LSPs
You can disable node protection on the RSVP interface. Link protection remains active. When this option is configured, the router can only initiate a next-hop bypass, not a next-next-hop bypass.
To disable node protection for bypass LSPs, include the no-node-protection statement:
You can include this statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection]
Configuring the Optimization Interval for Bypass LSPs
You can configure an optimization interval for bypass LSPs using the optimize-timer statement. At the end of this interval, an optimization process is initiated that attempts to either minimize the number of bypasses currently in use, minimize the total amount of bandwidth reserved for all of the bypasses, or both. You can configure an optimization interval from 1 through 65,535 seconds. A default value of 0 disables bypass LSP optimization.
When you configure the optimize-timer statement, bypass LSPs are reoptimized automatically when you configure or change the configuration of any of the following:
- Administrative group for a bypass LSP—The configuration for an administrative group has been changed on a link along the path used by the bypass LSP. Configure an administrative group using the admin-group statement at the [edit protocols rsvp interface interface-name link-protection] hierarchy level.
- Fate sharing group—The configuration for a fate sharing group has been changed. Configure a fate sharing group using the group statement at the [edit routing-options fate-sharing] hierarchy level.
- IS-IS overload—The configuration for IS-IS overload has been changed on a router along the path used by the bypass LSP. Configure IS-IS overload using the overload statement at the [edit protocols isis] hierarchy level.
- IGP metric—The IGP metric has been changed on a link along the path used by the bypass LSP.
To configure the optimization interval for bypass LSPs, include the optimize-timer statement:
You can include this statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection]
Configuring an Explicit Path for Bypass LSPs
By default, when you establish a bypass LSP to an adjacent neighbor, CSPF is used to discover the least-cost path. The path statement allows you to configure an explicit path (a sequence of strict or loose routes), giving you control over where and how the bypass LSP is established. To configure an explicit path, include the path statement:
For automatically generated bypass LSPs, include the path statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection]
For individually configured bypass LSPs, include the path statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection bypass bypass-name]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection bypass bypass-name]
Configuring the Amount of Bandwidth Subscribed for Bypass LSPs
You can configure the amount of bandwidth subscribed to bypass LSPs. You can configure the bandwidth subscription for the whole bypass LSP or for each class type that might traverse the bypass LSP. You can configure any value between 1 percent and 65,535 percent. By configuring a value less than 100 percent, you are undersubscribing the bypass LSPs. By configuring a value greater than 100 percent, you are oversubscribing the bypass LSPs.
The ability to oversubscribe the bandwidth for the bypass LSPs makes it possible to more efficiently use network resources. You can configure the bandwidth for the bypass LSPs based on the average network load as opposed to the peak load.
To configure the amount of bandwidth subscribed for bypass LSPs, include the subscription statement:
You can include this statement at the following hierarchy levels:
- [edit protocols rsvp interface interface-name link-protection]
- [edit logical-systems logical-system-name protocols rsvp interface interface-name link-protection]
Configuring Priority and Preemption for Bypass LSPs
When there is insufficient bandwidth to establish a more important LSP, you might want to tear down a less important existing LSP to release the bandwidth. You do this by preempting the existing LSP.
For more detailed information on configuring setup priority and reservation priority for LSPs, see Configuring Priority and Preemption for LSPs.
To configure the bypass LSP’s priority and preemption properties, include the priority statement:
For a list of hierarchy levels at which you can include this statement, see the statement summary section for this statement.
