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Viptela Documentation

BGP

Use the BGP template for all vEdge Cloud and vEdge router devices.

To configure the BGP routing protocol using vManage templates:

  1. Create a BGP feature template to configure BGP parameters, as described in this article. BGP can be used for service-side routing, to provide reachability to networks at the local site, and it can be used for transport-side routing, to enable communication between the vEdge router and other Viptela devices when the router is not directly connected to the WAN cloud. Create separate BGP templates for the two BGP routing types.
  2. Create a VPN feature template to configure VPN parameters for either service-side BGP routing (in any VPN other than VPN 0 or VPN 512) or transport-side BGP routing (in VPN 0). See the VPN help topic.

Navigate to the Template Screen and Name the Template

  1. In vManage NMS, select the Configuration ► Templates screen.
  2. In the Device tab, click Create Template.
  3. From the Create Template drop-down, select From Feature Template.
  4. From the Device Model drop-down, select the type of device for which you are creating the template.
  5. To create a template for VPN 0 or VPN 512:
    1. Click the Transport & Management VPN tab located directly beneath the Description field, or scroll to the Transport & Management VPN section.
    2. Under Additional VPN 0 Templates, located to the right of the screen, click BGP.
    3. From the BGP drop-down, click Create Template. The BGP template form is displayed. The top of the form contains fields for naming the template, and the bottom contains fields for defining BGP parameters.
  6. To create a template for VPNs 1 through 511, and 513 through 65530:
    1. Click the Service VPN tab located directly beneath the Description field, or scroll to the Service VPN section.
    2. Click the Service VPN drop-down.
    3. Under Additional VPN Templates, located to the right of the screen, click BGP.
    4. From the BGP drop-down, click Create Template. The BGP template form is displayed. The top of the form contains fields for naming the template, and the bottom contains fields for defining BGP parameters.

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  7. In the Template Name field, enter a name for the template. The name can be up to 128 characters and can contain only alphanumeric characters.
  8. In the Template Description field, enter a description of the template. The description can be up to 2048 characters and can contain only alphanumeric characters.

When you first open a feature template, for each parameter that has a default value, the scope is set to Default (indicated by a check mark), and the default setting or value is shown. To change the default or to enter a value, click the scope drop-down to the left of the parameter field and select one of the following:

Parameter Scope

Scope Description

Device Specific (indicated by a host icon)

Use a device-specific value for the parameter. For device-specific parameters, you cannot enter a value in the feature template. You enter the value when you attach a Viptela device to a device template.

When you click Device Specific, the Enter Key box opens. This box displays a key, which is a unique string that identifies the parameter in a CSV file that you create. This file is an Excel spreadsheet that contains one column for each key. The header row contains the key names (one key per column), and each row after that corresponds to a device and defines the values of the keys for that device. You upload the CSV file when you attach a Viptela device to a device template. For more information, see Create a Template Variables Spreadsheet.

To change the default key, type a new string and move the cursor out of the Enter Key box.

Examples of device-specific parameters are system IP address, hostname, GPS location, and site ID.

Global (indicated by a globe icon)

Enter a value for the parameter, and apply that value to all devices.

Examples of parameters that you might apply globally to a group of devices are DNS server, syslog server, and interface MTUs.

Configure Basic BGP

The following parameters are required (unless otherwise indicated) to configure BGP on a vEdge router:

To configure BGP, select the Basic Configuration tab and configure the following parameters. Parameters marked with an asterisk are required to configure BGP.

Parameter Name Description
Shutdown* Ensure that No is selected, to enable BGP.
AS number* Enter the local AS number.
Router ID Enter the BGP router ID, in decimal four-part dotten notation.
Propagate AS Path Click On to carry BGP AS path information into OMP.
Internal Routes Distance

Enter a value to apply as the BGP route administrative distance for routes coming from one AS into another.
Range: 0 through 255
Default: 0

Local Routes Distance Specify the BGP route administrative distance for routes within the local AS. By default, a route received locally from BGP is preferred over a route received from OMP.
Range: 0 through 255
Default: 0
External Routes Distance Specify the BGP route administrative distance for routes learned from other sites in the overlay network.
Range: 0 through 255
Default: 0

For service-side BGP, you might want to configure OMP to advertise to the vSmart controller any BGP routes that the vEdge router learns. By default, a vEdge router advertises to OMP both the connected routes on the vEdge router and the static routes that are configured on the vEdge router, but it does not advertise BGP external routes learned by the vEdge router. You configure this route advertisement in the OMP template for vEdge routers or vEdge software. See the OMP help topic.

For transport-side BGP, you must also configure a physical interface and a loopback interface in VPN 0. In addition, you should create a policy for BGP to advertise the loopback interface address to its neighbors, and apply the policy in the BGP instance or to a specific neighbor. See the Configuring Unicast Overlay Routing article for your software release.

To save the feature template, click Save.

CLI equivalent:

vpn vpn-id  
  router
    bgp local-as-number
      distance
        external number
        internal number
        local number        
      propagate-aspath
      router-id ip-address
      [no] shutdown

Configure the IPv4 Unicast Address Family

To configure global BGP address family information, select the IPv4 Unicast Address Family tab and configure the following parameters:

Tab Parameter Name Description
  Maximum Paths

Specify the maximum number of parallel IBGP paths that can be installed into a route table to enable IBGP multipath load sharing.

Range: 0 to 32

  Address Family Enter the BGP IPv4 unicast address family. Currently, only IPv4 is supported.
Redistribute
    Click the Redistribute tab, and then click Add New Redistribute.
  Protocol
Select the protocols from which to redistribute routes into BGP, for all BGP sessions. Options are Connected, NAT, OMP, OSPF, and Static. At a minimum, select the following:
  • For service-side BGP routing, select OMP. By default, OMP routes are not redistributed into BGP.
  • For transport-side BGP routing, select Connected, and then under Route Policy, specify a route policy that has BGP advertise the loopback interface address to its neighbors.
  Route Policy Enter the name of the route policy to apply to redistributed routes.
    Click Add to save the redistribution information.
Network
    Click the Network tab, and then click Add New Network.
  Network Prefix Enter a network prefix, in the format of prefix/length, to be advertised by BGP.
    Click Add to save the network prefix.
Aggregate Address
    Click the Aggregate Address tab, and then click Add New Aggregate Address.
  Aggregate Prefix

Enter the prefix of the addresses to aggregate for all BGP sessions, in the format prefix/length.

  AS Set Path Click On to generate set path information for the aggregated prefixes.
  Summary Only Click On to to filter out more specific routes from BGP updates.
    Click Add to save the aggregate address.

To save the feature template, click Save.

CLI equivalent:

vpn vpn-id  
  router
    bgp local-as-number
      address-family ipv4-unicast
        aggregate-address prefix/length [as-set] [summary-only]
        maximum-paths paths number
        network prefix/length 
        redistribute (connected | nat | omp | ospf | static)

Configure Neighbors

To configure a neighbor, select the Neighbor tab and click Add New Neighbor and configure the following parameters. For BGP to function, you must configure at least one neighbor.

Parameter Name Description
Address Specify the IP address of the BGP neighbor.
Description Enter a description of the BGP neighbor.
Remote AS Enter the AS number of the remote BGP peer.
Address Family

Click On and select the address family. Currently, the Viptela software supports only the BGP IPv4 unicast address family. Enter the address family information:

  • Address Family—Select the address family. Currently, the Viptela software supports only the BGP IPv4 unicast address family.
  • Maximum Number of Prefixes—Specify the maximum number of prefixes that can be received from the neighbor.
    Range: 1 through 4294967295
    Default: 0
    If you specify a maximum number of prefixes, you can also configure:
    • Threshold—Threshold at which to generate a warning message or restart the BGP connection. The threshold is a percentage of the maximum number of prefixes.
    • Restart Interval—How long to wait to restart the BGP connection.
      Range: 1 through 65535 minutes
    • Warning Only—Click On to only display a warning message, without restarting the BGP connection.
      You can specify either a restart interval or a warning only.
  • Route Policy In—Click On and specify the name of a route policy to apply to prefixes received from the neighbor.
  • Route Policy Out—Click On and specify the name of a route policy to apply to prefixes sent to the neighbor.
Shutdown Click On to enable the connection to the BGP neighbor.

To configure advanced parameters for the neighbor, click the Neighbor tab, and then click Advanced Options:

Parameter Name Description
Next-Hop Self Click On to configure the router to be the next hop for routes advertised to the BGP neighbor.
Send Community Click On to send the local router's BGP community attribute to the BGP neighbor.
Send Extended Community Click On to send the local router's BGP extended community attribute to the BGP neighbor.
Negotiate Capability Click On to allow the BGP session to learn about the BGP extensions that are supported by the neighbor.
Source Interface Address Enter the IP address of a specific interface of the neighbor that BGP is to use for the TCP connection to the neighbor.
Source Interface Name Enter the name of a specific interface of the neighbor that BGP is to use for the TCP connection to the neighbor, in the format geport/slot.
EBGP Multihop Set the time to live (TTL) for BGP connections to external peers.
Range: 0 to 255
Default: 1
Password Enter a password to use to generate an MD5 message digest. Configuring the password enables MD5 authentication on the TCP connection with the BGP peer. The password is case-sensitive and can be up to 25 characters long. It can contain any alphanumeric characters, including spaces. The first character cannot be a number.
Keepalive Time Specify the frequency at which keepalive messages are advertised to a BGP peer. These messages indicate to the peer that the local router is still active and should be considered to be available.
Specify the keepalive time for the neighbor, to override the global keepalive time.
Range: 0 through 65535 seconds
Default: 60 seconds (one-third the hold-time value)
Hold Time Specify the interval after not receiving a keepalive message that the local BGP session considers its peer to be unavailable. The local router then terminates the BGP session to that peer.
Specify the hold time for the neighbor, to override the global hold time.
Range: 0 through 65535 seconds
Default: 180 seconds (three times the keepalive timer)
Connection Retry Time Specify the number of seconds between retries to establish a connection to a configured BGP neighbor peer that has gone down.
Range: 0 through 65535 seconds
Default: 30 seconds
Advertisement Interval For the BGP neighbor, set the minimum route advertisement interval (MRAI) between when BGP routing update packets are sent to that neighbor.
Range: 0 through 600 seconds
Default: 5 seconds for IBGP route advertisements; 30 seconds for EBGP route advertisements

To save the feature template, click Save.

CLI equivalent:

vpn vpn-id  
  router
    bgp local-as-number
      neighbor ip-address        
        address-family ipv4-unicast
          maximum-prefixes number [threshold] [restart minutes | warning-only]
          route-policy policy-name (in | out)
        capability-negotiate
        description string        
        ebgp-multihop ttl        
        next-hop-self
        password md5-digest-string 
        remote-as remote-as-number        
        send-community
        send-ext-community
        [no] shutdown
        timers
          advertisement-interval number          
          connect-retry seconds          
          holdtime seconds        
          keepalive seconds        
        update-source ip-address

Configure Advanced Parameters

To configure advanced parameters for BGP, click the Advanced tab and configure the following parameters:

Parameter Name Description
Hold Time Specify the interval after not receiving a keepalive message that the local BGP session considers its peer to be unavailable. The local router then terminates the BGP session to that peer.
This hold time is the global hold time.
Range: 0 through 65535 seconds
Default: 180 seconds (three times the keepalive timer)
Keepalive Specify the frequency at which keepalive messages are advertised to a BGP peer. These messages indicate to the peer that the local router is still active and should be considered to be available.
This keepalive time is the global keepalive time.
Range: 0 through 65535 seconds
Default: 60 seconds (one-third the hold-time value)
Compare MED Click On to compare the router IDs among BGP paths to determine the active path.
Deterministic MED Click On to compare MEDs from all routes received from the same AS regardless of when the route was received.
Missing MED as Worst Click On to consider a path as the worst path if the path is missing a MED attribute.
Compare Router ID Click On to always compare MEDs regardless of whether the peer ASs of the compared routes are the same.
Multipath Relax Click On to have the BGP best-path process selct from routes in different in ASs. By default, when you are using BGP multipath, the BGP best path process selects from routes in the same AS to load-balance across multiple paths.

To save the feature template, click Save.

CLI equivalent:

vpn vpn-id  
  router
    bgp local-as-number
      best-path
        as-path multipath-relax
        compare-router-id
        med (always-compare | deterministic | missing-as-worst)
      timers
        holdtime seconds
        keepalive seconds
     

Release Information

Introduced in vManage NMS in Release 15.2.
In Release 17.1, add Propagate AS Path field.

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