Add Diverse Tunnels

You can pair Label Switched Paths (LSPs) so that they do not overlap at any point between their ingress (starting point) and egress (ending point). This is crucial for network resilience, as it ensures that if one path fails, the other remains operational.

There are three types of tunnel diversity:

Link Diversity—Ensures LSPs do not share common links. If one LSP uses a specific link, the other LSP in the pair will use a different link, thus avoiding shared points of failure.
SRLG (Shared Risk Link Group) Diversity—Ensures LSPs avoid links that share the same risk factors.
Site Diversity—Ensures LSPs avoid the same nodes and therefore the same sites. This is the most comprehensive form of diversity, as it includes both link and SRLG diversity.

Note: It is not possible to create a diverse group with more than two tunnels. If you attempt to add more tunnels to a diversity group, the additional tunnels may not maintain the expected diversity.

To implement tunnel diversity in your network:

Navigate to Observability > Network > Topology.
The Topology page is displayed with the topology map at the center and the network information table at the bottom of the page.
Navigate to the Tunnels tab.
Click the Provisioning drop down and select Diverse Tunnels.
The Add Diverse Tunnels page appears.
Complete the configuration on each tab according to the guidelines in Table 1.

Note:
Fields marked with an asterisk (*) are mandatory.
(Optional) From any tab, click Preview Path at the bottom of the page to view the path on the topology map.

Click Add to add the tunnel.

A confirmation message appears on the top of the page, indicating that diverse tunnels are created.

Table 1: Fields on the Add Tunnel Page
Field	Description
PROPERTIES
Provisioning Method	From the list, select one of the following methods to be used to provision the tunnel: PCEP (Path Computation Element Protocol)—The path computation element (PCE) initiates the tunnel and the associated configuration statements do not appear in the router configuration file. Upon provisioning, this tunnel is added as a PCE-initiated tunnel. This is the default provisioning method. NETCONF—The tunnel is statically provisioned and the associated configuration statements appear in the router configuration file. Upon provisioning, this tunnel is added as a device-controlled tunnel. Note: For Cisco IOS-XR routers, NETCONF-based tunnel provisioning has the same capabilities as PCEP-based tunnel provisioning. When provisioning tunnels by using NETCONF one at a time, the provisioning order might be sent before the response to a previous provisioning order is received. The second order might not have the correct bandwidth allocation information and the PCE might not be able to provide ECMP. We recommend provisioning multiple tunnels through NETCONF in one operation (bulk provisioning) in order to avoid this issue.
Provision Type	From the list, select the type of tunnel that you want to provision: RSVP SR (segment routing) SRv6
Diversity Group	Specify the name of the diversity group to which this tunnel belongs. If you want to create a diverse path for a pair of tunnels, then ensure that the tunnels belong to the same diversity group. Use alphabets, numbers, period(.), hyphen (-), colon (:), or underscore (_).
Diversity Level	Select one of the following diversity levels : Link—Two paths don’t intersect at any given link. Link diversity is the weakest. SRLG (Shared Risk Link Group)—Two paths don't intersect at any of the group’s links or nodes (aside from the source and destination). SRLG diversity includes link diversity. Site—Two paths don’t intersect at any given site (aside from the source and destination). Site diversity is the strongest as it includes SRLG and link diversity. The diversity level determines the constraints that must be applied during path computation to ensure diverse and optimal paths.
TUNNEL (Specify the following for Tunnel 1 and Tunnel 2.)
Name	Specify a unique name for the tunnel. You can use any number of alphanumeric characters, period, hyphens, colons, and underscores. For example, tunnel1. Note: If you are adding multiple parallel tunnels that will share the same design parameters, the name you specify here is used as the base for automatically naming those tunnels. See the Count and Delimiter fields in the Advanced tab for more information.
Device A	From the list, select the device that you want to use as the ingress node.
Device Z	From the list, select the device that you want to use as the egress node.
Planned Bandwidth	Specify the planned bandwidth (along with valid units, with no space between the bandwidth and units) for the tunnel. If you specify a value without units, bps is automatically applied. Valid units are: B or b M or m K or k G or g Examples: 50M, 1000b, 25g.
Planned Metric	Specify the static tunnel metric. The PCE uses this metric to route the tunnel instead of allowing the router to choose a path.
Setup	Specify the setup priority for the tunnel traffic. Priority levels range from 0 (highest priority) through 7 (lowest priority). The default is 7, which is the standard MPLS tunnel definition in Junos OS. Based on the setup priority, the PCE determines whether a new tunnel can be established by preempting an existing tunnel. The PCE can preempt the existing tunnel if: Setup priority of the new tunnel is higher than that of the existing tunnel. Preemption releases enough bandwidth for the new tunnel.
Hold	Specify the hold priority for the tunnel traffic. Priority levels range from 0 (highest priority) through 7 (lowest priority). The default is 7, which is the standard MPLS tunnel definition in Junos OS. Based on the hold priority, the PCE determines whether the tunnel can be preempted or not. If the hold priority for a tunnel is higher, it is unlikely for the tunnel to be preempted.
Color Community	Note: This field is available only for the SR provision type. Assign a color for a segment routing tunnel that can be used to map traffic on the tunnel. Range: 0 through 4294967295. A segment routing (SR) policy uses the color community value to steer traffic flows on to a tunnel. By using Color Community, you can steer traffic into SR LSPs.
FlexAlgo ID	Select the flex algo ID that you want to associate with the LSP. This field lists all the flex algo IDs in your network. When the LSP is provisioned, the LSP adheres to the pre-defined FAD constraints such as administrative group restrictions, optimizing traffic paths, and so on. You can select the flex algo ID only for SR (segment routing) and SRv6 LSPs.
CONSTRAINTS
Admin Group Include All	From the list, select one or more admin group bits for the tunnel to traverse links that include all of the admin groups specified in this field. The maximum selections allowed is 32.
Admin Group Include Any	From the list, select one or more admin group bits. The tunnel traverses links that include at least one of the admin groups specified in this field. The maximum selections allowed is 32.
Admin Group Exclude	From the list, select one or more admin group bits. The tunnel traverses links that do not include any of the admin groups specified in this field. The maximum selections allowed is 32.
Maximum Delay	Specify the maximum delay (in milliseconds) for the tunnel, which is used as a constraint for tunnel rerouting. For example, 2.
Maximum Hop	Specify an integer value for the maximum number of hops that the tunnel can traverse. For example, 2.
Maximum Cost	Specify an integer value for the maximum cost to be associated with the tunnel.