Requirements and Installation - NGA (PostgreSQL®)
Requirements
- An NGA installation and a PostgreSQL® installation.
- The recommended deployment scenario for both - the PSS and the SSS of the DRS system is NGA deployment - redundant scenario - PostgreSQL®. To install these two clusters, see chapter PostgreSQL® Database Cluster.
Installation
- Add a new CTRL manager to the console (start-mode: Always):
disRecSystem_NgaController.ctl -num 6 .
Note: for the NGA debug flags see chapter Debug Flags of the Disaster Recovery System.
- Start the importer thread on PSS and SSS and restart NGA after the setting was done on all 4 SCADA machines (make sure to choose a free port for the importer thread).
- The PostgreSQL® configuration must be changed so that the SSS can access the PSS DB and
vice versa. Edit the /var/lib/pgsql/data/pg_hda.conf file as follows:
For more information on the pg_hda.conf, see also: https://www.postgresql.org/docs/13/auth-pg-hba-conf.html) .
Note: Make sure that the firewall allows the PSS to connect to SSS database and vice versa.
- Configure the listening_address setting: listen_addresses = '*' instead of localhost in the postgresql.conf (this must be configured also if the DB runs on another machine than SCADA server). For how to configure the postgresql.conf, see chapter PostgreSQL® in a Distributed System.
- If you have more than one PostgreSQL® backend, make sure that only one of them is running in-proc and all the others as out-of-proc.
- Each of the out-of-proc backends requires a different (free) port in order to work properly.
Note: However, note all backends that serve as synchronizations source
must have one of the following execution types:
- In-Proc (Backend as Plugin)
-
Out-Of-Proc (Separate Process) / In-Proc for Direct Read
Only one PostgreSQL® backend can be started with Execution type1 - In-Proc (Backend als Plugin).