OSPF Tab

Configuration > Networking > Routing > OSPF

This tab manages OSPF (Open Shortest Path First) on LAN and WAN interfaces.

OSPF learns routes from routing peers, and then subnet shares them with EdgeConnect peers and/or BGP neighbors.

A route tag is applied to a route to better identify the source of the network it originated from. It is primarily used to filter routes from being redistributed in a routing loop.

A maximum of 64 OSPF neighbors and 64 BGP peers is supported per appliance, with 200 next-hops supported per interface.

• For BGP, only 64 peers can be added. For OSPF, more than 64 neighbors can be added, though an error will be logged.

• If more than 64 OSPF neighbors are added, the active OSPF neighbors are chosen in a deterministic manner. All OSPF neighbors that are added are queried in a sorted order using segment ID as the primary index and the neighbor IP address as the secondary index. For example, if there are 65 OSPF neighbors, the peer in the highest segment and with the highest IP address will be the one that is always dropped. It will not drop a random OSPF neighbor.

• Also, if there are 60 OSPF neighbors in the default segment, which always has ID:0, and 10 OSPF neighbors in segment 1, the 60 neighbors in the default segment will always be included, as well as the 4 neighbors in segment 1 with the lowest IP addresses.

Filter by Segment

To filter the rows displayed in the OSPF table by segment:

• Select Default from the Segment drop-down list to display for the system-supplied default segment, or

• Select one of the other listed segments, which reflect the custom segments defined using Routing Segmentation (Configuration > Networking > Routing > Routing Segmentation (VRF)).

Select All to display for all segments, which is the default setting

The table below describes the fields displayed for the OSPF configuration.

Select the edit icon in the OSPF table to edit and enable OSPF.

OSPF Edit Row

Use this dialog box to manage OSPF (Open Shortest Path First) on LAN and WAN interfaces.

OSPF learns routes from routing peers, and then subnet shares them with EdgeConnect peers and/or BGP neighbors.

To add an additional interface to an OSPF route, click Add in the Interfaces section.

NOTE: The BFD field in the Interfaces table on the OSPF dialog box is set to N/A if BFD is not supported on the appliance.

To configure or modify an OSPF route map, select the edit icon next to the Redistribute routes to OSPF field.

Add Interface

Complete the following fields to add an interface to OSPF.

OSPF Route Redistribution Maps

Route Maps are policies applied to IP routes during redistribution between routing protocols. They have Match Criteria and Set Actions that allow for filtering routes or modifying metrics and attributes for routes that meet the criteria defined in the match statement. Route-map rules follow a top-down order based on the sequence number defined for each entry.

EdgeConnect Enterprise supports applying Route Maps inbound from and outbound to BGP peers and outbound to OSPF neighbors and the SD-WAN Fabric. It is best practice to use Orchestrator to apply Route Maps using templates.

You can specify up to 20 OSPF route maps and 128 rules per route map.

You can specify up to 6 prefixes for each rule applied to a route map.

You can add, delete, rename, or clone route maps using this window. You can add rules to your route map by clicking Add Rule. A route map without any enabled rules is treated as a default deny all.

Prefix Match Criteria

The default for prefix match criteria is exact-match + greater-than. Both the specified prefix and any subnets of that prefix will be matched, up to a length of 32 for IPv4 or 128 for IPv6 (subnet sharing route maps only).

Less-than-or-equal-to (LE) and greater-than-or-equal-to (GE) clauses can also be applied to specify the inclusion of certain subnets.

To match a default-route, deny 0.0.0.0/1, deny 128.0.0.0/1, and then permit any.

GE Clause

If a GE clause is applied, the rule will also include all prefixes that have a prefix length greater than or equal to the GE value and less than or equal to 32 or 128 (for IPv6).

Example: A.B.C.D/X GE Y

In this example the following will be included:

• The exact match to A.B.C.D/X

• All the prefixes that belong to the subnet A.B.C.D/X that have a length greater than or equal to Y and less than or equal to 32

For example, you have a route map entry of 192.168.0.0/16 GE 24, and a peer advertises the following prefixes:

• 192.168.0.0/16

• 192.168.1.0/24

• 192.168.2.0/25

• 192.168.2.128/25

192.168.0.0/16 – The prefix length is 16, which is not greater than or equal to 24. This route does not match.

192.168.1.0/24 – The prefix length is 24, which is equal to the specified value. Therefore, this route matches the condition.

192.168.2.0/25 – The prefix length is 25, which is greater than or equal to 24. Therefore, this route matches the condition.

192.168.2.128/25 – The prefix length is 25, which is greater than or equal to 24. Therefore, this route also matches the condition.

So, the routes that would be matched by the given route map entry are:

• 192.168.1.0/24

• 192.168.2.0/25

• 192.168.2.128/25

LE Clause

If an LE clause is applied, the rule will also include all prefixes that have a prefix length less than or equal to the LE value.

Example: A.B.C.D/X LE Y

In this example the following will be included:

• The exact match to A.B.C.D/X

• All the prefixes that belong to the subnet A.B.C.D/X that have a length greater than or equal to X and less than or equal to 32

• All the prefixes that belong to the subnet A.B.C.D/X that have a length less than or equal to Y

For example, you have a route map entry of 192.168.0.0/16 LE 24, and a peer advertises the following prefixes:

• 192.168.0.0/16

• 192.168.1.0/24

• 192.168.2.0/25

• 192.168.2.128/25

192.168.0.0/16 – The prefix length is 16, which is less than or equal to 24. This route matches.

192.168.1.0/24 – The prefix length is 24, which is equal to the specified value. This route matches.

192.168.2.0/25 – The prefix length is 25, which is not less than or equal to 24. This route does not match.

192.168.2.128/25 – The prefix length is 25, which is not less than or equal to 24. This route does not match.

So, the routes that would be matched by the given route map entry are:

• 192.168.0.0/16

• 192.168.1.0/24

Combining LE and GE Clauses

Example: A.B.C.D/X LE Y GE Z

In this example the following will be included:

• The exact match to A.B.C.D/X

• All the prefixes that belong to the subnet A.B.C.D/X that have a length less than or equal to Y

• All the prefixes that belong to the subnet A.B.C.D/X that have a length greater than or equal to Z and less than or equal to 32

Exact Match

If both GE and LE clauses are specified and are equal, the rule will result in an exact match.

Example: A.B.C.D/X LE Y GE Y

In this example, the following will be included:

• The exact match to A.B.C.D/X

• The exact match to the subnet A.B.C.D/X that has a length equal to Y

You can specify the following fields in each rule for the selected route map.

Priority

Select Match Criteria

NOTE: The above fields in the right column will change depending on the source protocol chosen.

Set Actions

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