Configure BGP for IBM Cloud Connections

Before you begin, ensure you have completed the steps outlined in Add an IBM Direct Link Connection to a Cloud Router.

Add BGP information to the Cloud Router connection

Click the Cloud Router to expand its connections, and then click Configure BGP.

Screenshot of the Configure button in the PacketFabric portal

Complete the following fields and then click Submit.

BGP Settings

The ASN and IP addresses are completed on your behalf and should not be modified.

  • Header row
    • Field
    • Description
  • Row 1
    • Allow longer prefixes

    • This applies to the allowed incoming and outgoing prefixes that you list below.

      For example, say you list 172.16.2.0/24 as an allowed incoming prefix. You have three other cloud connections with the following outgoing prefixes:

      Connection A: 172.16.2.0/24
      Connection B: 172.16.0.0/16
      Connection C: 172.16.2.128/25

      If you do not select this option, only routes from Connection A are allowed.

      If you select this option, the routes from Connection A and Connection C are allowed.

NAT settings

This option appears if you selected a NAT-capable on-ramp.

Prefixes to NAT
The prefixes from the cloud that you want to associate with the NAT pool.
NAT Pool Prefixes
This is autofilled with the PacketFabric router CIDR. All prefixes that are NATed on this connection will be translated to the pool prefix address.
Allowed prefixes to cloud

This is a list of addresses that you want to allow into your IBM Cloud VPC. These can be addresses from other cloud environments or from a different IBM Cloud VPC.

  • Row
    • Field
    • Description
  • Row
    • ASN prepend

    • Number of additional times to add the ASN to the BGP path, resulting in a higher path length.

      Routes with higher path length (a higher ASN prepend value) have a lower priority.

  • Row
    • MED

    • The multi-exit discriminator (MED) value.

      When the same route is advertised in multiple locations, those with a lower MED are preferred by the peer AS.

  • Row
    • Prefix/Mask
    • Enter an allowed IP address range in CIDR format. You can add up to 1000 prefixes.
Allowed prefixes from cloud

This is a list of addresses from within the IBM Cloud environment that you want to advertise to other clouds. This can include the VPC internal space and any routes you have created.

  • Row
    • Field
    • Description
  • Row
    • Local preference
    • When the same route is received in multiple locations, those with a higher local preference value are preferred by the PacketFabric Cloud Router.
  • Row
    • Prefix/Mask
    • Enter an allowed IP address range in CIDR format. You can add up to 1000 prefixes.