Have questions? Stuck? Please check our FAQ for some common questions and answers.

You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 4 Next »

 

Segment Routing Group Handling:


SR GroupKey data model

Segment Routing application interacts with the Group subsystem using the below SR specific GroupKey. So SR application associate a SRDefaultGroupKey or SRPolicyGroupKey for every group it creates. The SRGroupKey consists of collection of <PortNumber + Label Stack to be pushed on that port> where leftmost label representing the outermost label and rightmost label representing innermost label to be pushed.

 

For e.g. a ECMP group with two buckets pushing label L1 and output to two ports P1 and P2 respectively can be represented with a SRDefaultGroupKey {{P1, L1}, {P2, L1}}. 


Default Group Handling

For every new device detected, the SR application would initiate default group handling procedures for that device.

  • @Activation
    • Get the Segment IDs of all devices in the network
  • @LINK_UP involving one of device ports
    • Find the Neighbor Device ID
    • If (Neighbor is already present in the database for this device)
      • That means this new link is part of group of links to that Neighbor (e.g. LAG)
      • Determine all SRDefaultGroupKeys that are impacted due to this new link from the information of existing device ports and Segment IDs
      • Invoke "addBucketsToGroup()" API of the GroupService with a new SRDefaultGroupKey for all the impacted Groups
      • Updated Neighbor database with this new port
    • Else
      • That means this new link discovers a new neighbor

 

Segment Routing application interacts with the Group subsystem using the below SR specific GroupKey. So SR application associate a SRDefaultGroupKey or SRPolicyGroupKey for every group it creates. The SRGroupKey consists of collection of <PortNumber + Label Stack to be pushed on that port> where leftmost label representing the outermost label and rightmost label representing innermost label to be pushed.

 


 

Default Group Handler & Recovery

During Start-up:

Create Segment Id database of all the nodes in the network

Get all devices from Topology service

Add to above list when DEVICE_ADDED event received

For each switch that this instance is master,

If the Group subsystem peforming Group AUDIT, then wait until AUDIT completes

Create Neighbor list

Get all outgoing links from Link service

Update above list when LINK_ADDED event received

Get all Groups from the Store

Perform Audit using above Neighbor list

Policy Group Handler & Recovery

While creating the tunnel, ensure all the stitched groups are created before creating the Group chain in the ingress router

Similarly, while deleting the tunnel, ensure the group is deleted at ingress router before deleting any stitched groups

Group Event Handling

  • No labels