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Known limitations

Known limitations

Known limitations are as follows:

  • VPC networking doesn't consider the AS path length when selecting the best route for network traffic and therefore, AS prepends configured on direct links have no effect when VPCs are directly connected. However, you can use a transit gateway between the direct link and VPC in some topologies to achieve the desired effect. For planning considerations, see Using AS prepends with VPN connections.
  • Each IBM Cloud Direct Link connection requires a unique order. If you require multiple connections, open an IBM Cloud Direct Link order for each connection.
  • Direct Link Dedicated is a switchport in access mode. Currently, 802.1q is not supported.
  • IBM Cloud Direct Link requires BGP to establish the routes to a customer's remote network.
  • Each IBM Cloud Direct Link service is not redundant. Diversity can be supplied by IBM for multiple direct links. However, customers must build redundancy in their own BGP schemes.
  • If you want to connect to the classic infrastructure, be aware that IP subnet overlaps might exist and require exception approval. For more information, see Configuring BGP.
  • The IBM Cloud services network isn't accessible directly from your remote networks.
  • IBM Cloud doesn't permit customers to back haul traffic between their remote sites across the IBM Cloud backbone. Use IBM Cloud Direct Link to let your remote networks communicate privately with your IBM Cloud infrastructure.
  • IBM Cloud Direct Link requires you to use a VRF (Virtual Routing and Forwarding) instance.
  • VRF isn't fully compatible with the IBM Cloud SSL and IPsec VPN services.
  • The IBM Cloud fees for Direct Link Dedicated cover the cost of port termination on the IBM Cloud infrastructure. Customers are responsible for any fees that are associated with reaching the PoP from a remote network and any cross-connects needed within the PoP facility. IBM Cloud does not order a cross-connect on any customer's behalf.
  • IBM Cloud does not colocate any customer equipment in our network PoPs. Customers must work with their provider to determine whether they need to colocate any equipment in the facility where the IBM Cloud network PoP exists.
  • Direct Link Dedicated is a switchport in access mode. Currently, 802.1q is not supported.