1. Main function
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  --- initialize discovery client
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   --- initialize logger
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    --- clean message queue
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     --- create Zookeeper client = elect master, after election start schema_transformer

2. Run schema transformer
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   --- Initialize introspect
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    --- Update connection state
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     --- Connect to config API
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      --- Create schema transformer instance

3. Schema transformer init
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   --- Initialize AMPQ
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    --- Initialize Cassandra
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     --- ServiceChain init (step 4.)
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      --- Run reinit of the resources (step 5.)

4. ServiceChain init
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   --- Read all service chains from config database
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    --- Check the chains if they are valid or not, if not mark them to deletion 

5. Reinit   
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   --- Run reinit of routing instances = check if routing instance still needed , if not mark for deletion
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    --- Check ACL if belongs to VN or SG, if not delete it
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     --- Update security groups
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      --- Run reinit of Route targets = Go through all RT, if RT have back ref to routing instance or to logical router 
          keep this RT, else delete this RT if no back_ref exists
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       --- Free RT from database
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        --- Check if RI of the VN has flag for deletion and check they sould be deleted
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         --- Network policy reinit
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          --- Reinit Virtual Machine Interface Check for updating virtual machine interface properties
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           --- Reinit Instance IPs and Floating IPs
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            --- Reinit Service instances = check virtual machine back refs, try locate VM from back refs, if exists VM name to the Service instance back ref list
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             --- Reinit Routing Policy = get routing instance refs and add the routing instance under the Routing policy and set RP as ref for RI
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              --- Reinit route aggregates
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               --- Reinit of Port tuple
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                --- Reinit of BGPaaS
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                 --- Reinit Route Tables
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                  --- Evaluate each VN = check for changes in VN policys, acls, interfaces, service chains, delete old network connections,  
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                   --- Process stale objects = Go through all SI, delete SI with delete flag and update route targets