BGP Tab

Configuration > Networking > Routing > BGP

On this tab, you can configure BGP (Border Gateway Protocol) for appliances and add their BGP peers (also known as BGP “neighbors”). You can also add and modify peer-based advertisement and redistribution rules. EdgeConnect has the following behaviors relative to communities:

• EdgeConnect will propagate any existing communities and can be configured to assign and append new communities, remove, or replace all communities for routes advertised to peers.

• Appliances can display up to ten communities per route.

• Appliances subnet-share communities with their EdgeConnect peers.

• Appliances advertise communities to remote peers, if learned from EdgeConnect peers.

• Appliances advertise communities to BGP neighbors.

• All BGP-learned subnets also appear in the appliance Routes table, displayed on the Routes configuration page. In addition, any AS Path or BGP Community information learned with a particular subnet will also be displayed with that subnet entry in the table.

• BGP route updates are not refreshed unless the peer specifically asks for it. To update the BGP routes, go to the Peers table and select Soft Reset in the desired row.

• BGP Equal-cost multi-path (ECMP) is supported for eBGP and iBGP. Multiple next-hops will be installed for the same prefix if all BGP path attributes are the same, enabling BGP to load balance egress traffic across multiple peers.

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

• A small set of community numbers are used as internal communities that represent the source domain of a particular route:

  Value	Description
  100	Locally configured
  101	Subnet shared (learned from another appliance)
  102	Local BGP
  103	Remote BGP (learned from another appliance)
  104	Local OSPF
  105	Remote OSPF (learned from another appliance)

  These internal community values only use the appliance’s local ASN in the ASN portion of the community. When the ASN portion of an attached community exactly matches the local ASN and the community portion exactly matches one of these internal values, they are flagged as internal communities only and stripped when advertising the route to BGP peers.

Click the Summary button on the BGP tab to display configuration details associated with the local appliance, such as its local AS number and router ID. Click the icon in the BGP State Details column to display a summary, including the number of routes learned and advertised via BGP by this appliance.

Click the Peers button on the BGP tab to display information about all configured peers for the appliances selected in the appliance tree. Click the icon in the Peer Details column to display the connection status of each peer that is configured for the appliance.

Filter by Segment

To filter the rows displayed in the BGP 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 BGP configuration.

To edit the BGP configuration for one of the listed appliances, click the edit icon in the left column of the table.

BGP Information

Use this window to enable BGP for your appliances and to configure BGP peers. Complete the following steps to start BGP configuration.

1. Move the toggle to Enable BGP.

2. Complete the following fields.

   Field	Description
   Autonomous system number (ASN)	Configure this number as needed for your network.
   Router ID	This router identifier is the IPv4 address by which the remote peer can identify this appliance for purposes of BGP.
   Route Target	The BGP route target that identifies the routes associated with a segment. The route target must be in the following form: 2bytesASN:4bytesID or 4byteASN:2byteID (for example, 65001:1200). NOTE: Route target is available for all segments.
   Import:Export	Select this check box to specify a unique import and export value.
   Graceful restart	Enable receiver-side graceful restart capability. EdgeConnect retains routes learned from the peer and continues to use it for forwarding (if possible) if/when a BGP peer goes down. The retained routes are considered stale routes. They will be deleted and replaced with newly received routes. Max Restart Time – Specifies the maximum time (in seconds) to wait for a Graceful Restart capable peer to come back after a peer restart or peer session failure. Stale Path Time – Specifies maximum time (in seconds) following a peer restart that EdgeConnect waits before removing stale routes associated with that peer.
   AS path propagate	Select this check box to enable this appliance to send the full AS path, associated with a prefix to other routers and appliances, avoiding routing loops. This will provide the learned path from an external prepend between a remote BGP site to local BGP peers.
   Log BGP update messages	Select this check box to enable logging of BGP peer messages on the segment. This feature provides detailed logging of BGP update messages exchanged between BGP peers. It captures and logs every detail for each update, whether sent or received, including key attributes such AS Path list, routes, next-hop, origin, MED, and so on as they are shared with or received from a BGP peer.

3. Under the Common settings for all segments header, complete the following fields:

   Field	Description
   Max route updates per peer	The maximum number of route updates for each peer running route loop detection. The default value is 10, and the range is 5–100.
   Detection interval	The interval, in minutes, at which route advertisement loop detection runs. A route advertisement loop occurs when the same route is being advertised, removed, and re-advertised repeatedly within a short time period. The default value is 15, and the range is 1–60.

To add a BGP peer, select Add. The Add Peer dialog box opens.

Add Peer

Complete the following fields to add a BGP peer.

NOTE: Multiple address families are not supported on a single BGP peer. You must configure a separate BGP peer for each address family. IPv6 peers are only capable of exchanging IPv6 routes. IPv4 peers are only capable of exchanging IPv4 routes.

BGP Inbound and Outbound 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 BGP inbound route maps, 20 BGP outbound route maps, and 128 rules per route map.

You can specify up to 6 comma separated 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 (Inbound and Outbound)

Select Match Criteria (Inbound)

Select Match Criteria (Outbound)

Set Actions (Inbound and Outbound)

The following table describes the redistribution commands supported in the BGP routing protocol.

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