You can add a segment routing tunnel with an anycast group as
the destination, so that the traffic is routed to any one of the nodes that is part of the
anycast group.
To add a segment routing tunnel with an anycast group as the
destination:
Select 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.
In the Anycast Group tab, select Provisioning > Add Anycast Group
Tunnel.
The Add Anycast Group Tunnel page appears.
Complete the configuration on each tab according to the guidelines in Table 1.
Note:
Fields marked with an asterisk (*) are mandatory.
(Optional) You can click Preview Path at the bottom of the page
to see the path drawn on the topology map.
Click Add to add the tunnel.
A confirmation message appears on the top of the page, indicating that a provision
anycast tunnel request was successfully created:
If you have the Auto-approve permission assigned to your user role, the request is
automatically approved and deployed on the devices.
If you don't have Auto-approve permission, the request must be manually approved
and then,deployed by a user having the required permissions. See About the Change Control Management Page.
The tunnel then appears in Tunnel tab of the network information table (in the Topology
page).
Table 1: Fields on the Add Anycast Group Tunnel Page
Field
Description
Properties
Provisioning Method
From the list, select one of the following methods to be used to provision
the tunnel:
NETCONF (default)—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.
PCEP (Path Computation Element Protocol)—The tunnel is initiated by the
path computation element (PCE) and the associated configuration statements
do not appear in the router configuration file. Upon provisioning, this
tunnel is added as a PCE-initated tunnel.
Note:
For IOS-XR routers, NETCONF-based tunnel provisioning has the same
capabilities as PCEP-based tunnel provisioning.
Provision Type
Displays the type of tunnel to be provisioned—SR (segment routing).
Name
Specify a unique name for the tunnel.
You can use any number of alphanumeric characters, hyphens, and underscores.
Node A
From the list, select the node that you want to use as the ingress node.
Node Z
Do one of the following:
If you want the traffic to be routed to a single node, select
that
node as the egress node.
If you want the traffic to be routed to one of the nodes in an anycast
group, click the toggle button (Select destination as anycast
group) and select the anycast group from the
list.
By default, this toggle button is disabled.
Admin Status
The Path Computation Server (PCS) uses the administration status of the
tunnel to decide whether to route or provision, or both route and provision
the tunnel.
If the tunnel is routed, no traffic flows through the tunnel and its
operational status is Up. If the tunnel is provisioned,
traffic flows through the tunnel and its operational status is
Active.
Select one of the following options as the administration status:
Up—If you select this option, the PCS routes and provisions the
tunnel.
Planned—If you select this option, the PCS routes the tunnel and reserves
capacities for the tunnel. However, the PCS doesn’t provision the
tunnel.
Shutdown—If you select this option, the PCS neither routes nor provisions
the tunnel. The tunnel is maintained in the datastore and is associated
with a persist state so that the tunnel can be brought back up at a later
time, if required.
Path Type
From the list, select primary, secondary, or standby as the path type.
Path Name
Specify the name for the path.
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 applied.
Valid units are:
B or b
M or m
K or k
G or g
Examples: 50M, 1000b, 25g.
Bandwidth Sizing
Note:
This option is displayed only when you select PCEP as the provisioning
method.
Click the toggle button to enable or disable (default) bandwidth sizing for
the tunnel.
If you enable bandwidth sizing, the tunnel is included in the periodic
re-computation of planned bandwidth based on aggregated tunnel traffic
statistics.
Adjustment Threshold (%)
Note:
This option is available only when you enable bandwidth sizing.
Specify the sensitivity (in %) of the automatic bandwidth adjustment.
The new planned bandwidth is only considered if it differs from the existing
bandwidth by the value of this setting or more. The default value is 10%.
Minimum Bandwidth
Note:
This option is available only when you enable bandwidth sizing.
Specify the minimum 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 applied.
If the new planned bandwidth is less than the minimum setting, the PCE
signals the tunnel with the minimum bandwidth. However, if the new planned
bandwidth falls in between the maximum and minimum settings, The PCE signals
the tunnel with the new planned bandwidth.
The valid units are:
B or b
M or m
K or k
G or g
Examples: 50M, 1000b, 25g.
Maximum Bandwidth
Note:
This option is available only when you enable bandwidth sizing.
Specify the maximum 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 applied.
If the new planned bandwidth is greater than the maximum setting, the PCE
signals the tunnel with the maximum bandwidth. However, if the new planned
bandwidth falls in between the maximum and minimum settings, the PCE signals
the tunnel with the new planned bandwidth.
The valid units are:
B or b
M or m
K or k
G or g
Examples: 50M, 1000b, 25g.
Minimum Variation Threshold
Note:
This option is available only when you enable bandwidth sizing.
Specify the sensitivity of the automatic bandwidth adjustment when the new
planned bandwidth is compared to the current planned bandwidth.
Default: Zero.
The new planned bandwidth is only considered if the difference is greater
than or equal to the value of this setting. Because it is not a percentage,
this can be used to prevent small fluctuations from triggering unnecessary
bandwidth changes.
If both the adjustment threshold and the minimum variation threshold are
greater than zero, both settings are taken into consideration. In that case,
the new planned bandwidth is considered if the percentage difference is
greater than or equal to the adjustment threshold, and, the actual difference
is greater than or equal to the minimum variation.
Color Community
Note:
This field is available only for segment routing tunnels.
Assign a color for the segment routing tunnel that can be used to map traffic
on the tunnel.
Use Penultimate Hop as Signaling Address
Note:
This field is available only for segment routing tunnels.
Click the toggle button to enable the PCS to use the penultimate hop as the
signaling address for Egress Peer Engineering (EPE).
If you haven’t specified a color community, the setting applies to all
traffic. If you’ve specified a color community, the setting applies to traffic
in that color community.
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 existing tunnel can be
preempted if the setup priority of the new tunnel is higher than that of the
existing tunnel and the 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 an tunnel is higher, it is unlikely
for the tunnel to be preempted.
Planned Metric
Specify the static tunnel metric.
The PCE uses this metric to route the tunnel instead of allowing the router
itself to choose a
path.
Routing Method
From the list, select a routing method for the tunnel to specify whether the
PCE should compute and provision the path for the tunnel or not:
The available options are:
routeByDevice—This is the default routing method when a PCC-controlled
tunnel is created or learned by the PCE. For this method, The PCE does not
compute and provision a path.
This method is appropriate for three types of tunnels: RSVP TE
PCC-controlled tunnels, segment routing PCEP-based tunnels, and segment
routing NETCONF-based tunnels.
Other routing methods (default, delay, adminWeight, constant, distance,
ISIS, OSPF)—When a PCC-controlled tunnel has a routing method that is not
routeByDevice, the PCE computes and provisions the path as a strict
explicit route when provisioning the tunnel. The tunnel’s existing
explicit route might be modified to a PCE-computed strict explicit route.
For example, a loose explicit route specified by you or learned from the
router would be modified to a strict explicit route.
Binding SID
Note:
This field is available only for segment routing tunnels with NETCONF as
the provisioning type.
Specify the numerical binding SID label value.
This value then becomes the label that represents the path defined by the
hops you specify on the Path tab (which are the hops that make up the private
forwarding adjacency link).
Range: 1000000 to 1048575.
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.
The admin group bits are mapped to meaningful names, such as colors
(configured from the Configuration > Network > Admin Group page), so
that you can easily differentiate the different traffic routes in the display
and also use coloring constraints to influence the path of the tunnel.
Admin Group Include Any
From the list, select one or more admin group bits for the tunnel to traverse
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 for the tunnel to traverse
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.
Maximum Hop
Specify an integer value for the maximum number of hops that the tunnel can
traverse.
Maximum Cost
Specify an integer value for the maximum cost to be associated with the
tunnel.
Advanced
Count
Specify the number of parallel tunnels to be created between two
endpoints.
These tunnels share the same design parameters as specified in the
Constraints tab.
Note:
Creating parallel tunnels in this manner is different from provisioning
multiple tunnels (Provisioning > Multiple Tunnels)
where you configure Design parameters separately for each tunnel.
Delimiter
Note:
This field is available only when the count value is greater than 1.
Specify a delimiter value, which can consist of alphanumeric characters and
special characters except space, comma (,), and semicolon (;).
This value is used in the automatic naming of parallel tunnels that share the
same design parameters. The PCE names the tunnels using the name you enter in
the Properties tab and appends the delimiter value plus a unique numerical
value beginning with 1
Example: myTunnel_1, myTunnel_2, and so on.
Description
Specify a comment or description for the tunnel for your reference.
IP Z
From the list, select the IP address for Node Z (that is, the egress
node).
The options in the list are populated based on the Node Z that you selected
in the Properties tab in this page.
Symmetric Pair Group
Specify a unique name for the symmetric pair group. You can use any number of
alphanumeric and special characters.
Tunnels with the same group name (as specified in this field) are considered
part of a symmetric pair group.
You create a symmetric pair group so that the tunnel from the ingress node to
the egress node follows the same path as the tunnel from the egress node to
the ingress node. When there are two tunnels with the same end nodes but in
opposite directions, the path routing uses the same set of links. For example,
suppose Tunnel1 source to destination is NodeA to NodeZ, and Tunnel2 source to
destination is NodeZ to NodeA. Selecting Tunnel1-Tunnel2 as a symmetric pair
group places both tunnels along the same set of links. Tunnels in the same
group are paired based on the source and destination node.
Create Symmetric Pair
Note:
This option is displayed only when you specify a symmetric pair group.
Click the toggle button to enable the creation of a symmetric pair.
This option allows you to create the symmetric pair in the same operation as
creating the tunnel.
Diversity Group
Specify the name of a group of tunnels to which this tunnel belongs, and for
which diverse paths are desired.
Diversity Level
From the list, select the level of diversity for the tunnel:
Default—No diversity level will be applied.
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.
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.
Link—Two paths don’t intersect at any given link. Link diversity is the
weakest.
Slice Include All
Specify one or more topology slice IDs for the tunnel to be routed over links
and nodes, that are tagged with all the slice IDs specified in this field.
Slice Include Any
Specify one or more topology slice IDs for the tunnel to be routed over links
and nodes, that are tagged with atleast one of the slice IDs specified in this
field.
Slice Exclude
Specify one or more topology slice IDs for the tunnel to be routed over links
and nodes, that are not tagged with any of the slice IDs specified in this
field.
Route on Protected IP Link
Click to enable the toggle button if you want the route to use protected IP
links as much a possible.
Custom Attributes
Click the Add icon (+) to specify provisioning
properties not directly supported by the GUI.
For example, you cannot specify a hop-limit when you provision a tunnel.
However, you can add hop-limit as a custom attribute.
At the edit > protocols > mpls > label-switched-path hierarchy level
in the NETCONF template file, you must add the statements needed to provision
with the property you are adding. If the property is present with the defined
value, then the provisioning statement is
executed.
Path
Routing Path Type
From the list, select the type of routing path for the tunnel:
Dynamic—Allows the PCE to compute a path without imposing any path
restrictions.
Required—Prevents the PCE from using any other path for this tunnel. If
the required path is not viable and available, the tunnel is down and the
PCE does not perform computation to look for an alternate path.
Preferred—Instructs the PCE to use this path over any other, as long as
it is viable and available. If it is not viable and available, the PCE
computes an alternate path.
Add Hop
This option available only if the routing path type is Preferred or
Required.
Click the Add (+) icon or click Add
Hop. From the list, select an option as the first hop between
node A and node Z.
In addition, click the toggle button next to this field to specify whether
the hop is strict or loose:
If you specify the hop as strict, the tunnel must take a direct path from
the previous router to this router.
If you specify the hop as loose, the tunnel can take any path to reach
this router; the PCE chooses the best path.
To add additional hops, click the + icon again. You
can add a maximum of 37 hops.
Note:
When specifying a loose hop, you can choose from all links in the network.
When specifying a loose hop for a Required path, anycast group SIDs are also
available for selection.
Schedule
Plan
No Schedule—(Default) tunnel provisioning is not scheduled (that is,
tunnels are provisioned immediately upon submission of the provisioning
request).
Once—In the Start and End fields that appear, specify the start date and
time and end date and time at which you want to provision the tunnels. The
tunnels are provisioned once at the specified date and time.
Recurring Daily—Specify the start and end dates and start and end times
in the Start Date, End Date, Start Time, and End Time fields that appear.
The tunnels are provisioned daily.