When topology split is invoked, the topology-split driver runs scripts that read the tsm.conf and topo-split.conf files. If the NumberOfDomains configuration parameter is set to the number of domains in the topo-split.conf file, additional scripts run, such as the ones that perform the following tasks:
Run the topology-split algorithm, which analyzes and splits the discovered topology into the user-specified number of domains. The topology-split algorithm may be run more than once, depending on the value of the IsTrialLearningEnabled configuration parameter, and on the value of the NumberOfRetries configuration parameter if the topology split fails.
Any retry of a failed topology split is performed as an incremental topology split.
In normal mode (IsTrialLearningEnabled = FALSE), create a seed file for each domain and write the seed files to the Topology Split Manager’s local/logs directory.
In trial learning mode (IsTrialLearningEnabled = TRUE and IsSplitFromScratch = TRUE), create a seed file for each domain for each successful run of the topology-split algorithm, and write the seed files to a Topology Split Manager’s <TSM name>.trial.<num> directory.
For a discovery that includes Hot Standby Router Protocol (HSRP) groups and/or Virtual Router Redundancy Protocol (VRRP) groups, make corrections for any HSRP or VRRP group that is split between domains as a result of the topology split, to ensure that at least one of the domains includes the complete topology for an HSRP or VRRP group. All of the devices for a “complete” group are added to the domain that contains the lowest number of managed network adapters.