Multi WAE Collection Overview
Multi WAE collection allows you to split the WAE topology into smaller WAE instances. Collection is done in parallel for each WAE instance. The plan file generated after collection from each WAE instance is then merged to a single plan file for the entire network.
Multi WAE is particularly useful for large networks. It improves performance and reduces the collection time by performing collection and model building of few NIMOs in parallel using different WAE instances. Any change in the network is propagated to that particular WAE instance final network using notification. The merge NIMO, when run will propagate to the final merged network.
Each WAE instance has its own WAE process running with access to WAE CLI and WAE GUI. WAE Design can also be installed in each of the WAE instances and can be used to view the plan files from each instance.
The SR-PCE agent is configured in active state only on one WAE instance and this is called the WAE Scale Primary instance. SR-PC agent is disabled for other WAE instances and these are called WAE Scale Secondary instances. Each WAE instance is given a unique scale ID which is shared between the HA primary and HA secondary instances. This ID is called the Scale ID.
If a network has around 3k devices within the single SR-PCE server, then Multiple WAE instances can be configured to process a subnetwork of the topology. Here the split of the network is done by SR-PCE agent.
The BGP-LS XTC NIMO which is the first NIMO to run after SR-PCE agent is configured to read the sub network database file instead of full SR-PCE agent output database. BGP-LS XTC NIMO processes the sub network and provides input to other NIMOs. The remaining NIMOs work on the sub network. Output from SAgE contains topology and traffic information pertaining to the sub network. Merge NIMO merges the output from each WAE instance SAgE network.
NIMOs like Netflow NIMO, Multicast NIMO, and Demands NIMO require full network as source network and hence must be run after the merged NIMO. It is recommended to have a separate DARE and SAgE workflow starting with merged NIMO as the only source and the remaining required dependency NIMO like Demands, etc as dependency network.
For multiple AS typologies, recommended way is to configure separate WAE instances for each AS and then merge their SAgE plan files to get full network topology. A non multi WAE approach is recommended when multiple AS topology is being discovered. It is simpler and has no dependency on multi WAE.