The virtual service placement is done based on the BGP peer label configuration.
Use Case 1
A virtual service VIP with a label X, for instance, can only be placed on SE’s having BGP peering with peers containing label X.
VRF |
BGP Peer Labels |
VSVIP BGP Peer Labels |
|---|---|---|
Network 1 |
Label 1 |
Label 1 |
Network 2 |
Label 2 |
Label 2 |
Network 3 |
Label 3 |
Label 3 |
Network 4 |
Label 4 |
Label 4 |
Network 5 |
Label 5 |
In this case, the virtual service is placed on Network 1, Network 2, Network 3, and Network 4.
Use Case 2
A virtual service VIP with no labels can be placed on SE’s having BGP peering with peers in any subnet. That is, if the BGP peer has labels but BGP virtual service VIP does not have a label, the virtual service VIP is advertised to be placed on all peer NICs (maximum of four distinct peer networks).
VRF |
BGP Peer Labels |
VSVIP BGP Peer Labels |
|---|---|---|
Network 1 |
Label 1 |
|
Network 2 |
Label 2 |
|
Network 3 |
Label 3 |
|
Network 4 |
Label 4 |
|
Network 5 |
Label 5 |
In this case, the virtual service is randomly placed on any one of the four networks.
Use Case 3
If the virtual service VIP is updated to associate a label later, the SE receives the virtual service SE_List update, the VIP is withdrawn from all the other peers and is placed only on the NIC pertaining to the peer with the matching label (disruptive update). For instance, the initial configuration can be done as below:
VRF |
BGP Peer Labels |
VSVIP BGP Peer Labels |
|---|---|---|
Network 1 |
Label 1 |
Label 1 |
Network 2 |
Label 2 |
Label 2 |
Network 3 |
Label 3 |
Label 3 |
Network 4 |
Label 4 |
|
Network 5 |
Label 5 |
Updates done on the VS VIP to associate the labels will lead to disruptive update of the virtual service.
VRF |
BGP Peer Labels |
VSVIP BGP Peer Labels |
|---|---|---|
Network 1 |
Label 1 |
Label 1 |
Network 2 |
Label 2 |
Label 2 |
Network 3 |
Label 3 |
Label 3 |
Network 4 |
Label 4 |
Label 4 |
Network 5 |
Label 5 |
Use Case 4
If the label is removed from the virtual service and the virtual service VIP is left with no label, then the virtual service VIP is placed on all the peer - NICs (maximum of four distinct peer networks).
Use Case 5
If the virtual service VIP is created with labels for which there is no matching peer, VS VIP creation is blocked due to invalid configuration, whether it is at the time of creating the virtual service or if the virtual service VIP label is updated later.
VRF
BGP Peer Labels
VSVIP BGP Peer Labels
Network 1
Label 1
Label 5
Network 2
Label 2
Network 3
Label 3
Network 4
Label 4
In this case, since there are no matching VS VIP BGP-peer labels, VS VIP creation is blocked with No BGP Peer exists with matching labels error.
