>-Does the compiled Policy include the database, so in case an error which is based on a db-change can be reverted until the real error is found?
The compiled policy includes the objects to the degree that they apply to that specific firewall's policy. I don't think it is a complete list of objects but I could be wrong. You cannot revert the live configuration displayed in the SmartConsole back to the state when a policy was compiled and installed as shown via the Installation History screen.
> -Where (which folder on the management) are the compiled policies, shown in "Installation History" saved?
In the postgres database located in $CPDIR/database/postgresql/data, but you can't typically access these directly from the CLI although it is probably possible via the psql_client command.
> - How large are these files? (GB or MB)
I'm not sure if the compiled policy is stored in its entirety or if it is simply a set of database transactions to recreate the original compiled policy. In the former case the size would be roughly the same as you would see on the SMS by running this command: du -sh $FWDIR/state/(gateway name)/FW1. In the latter case the amount consumed would be significantly less.
If you haven't already, please see my article about R80+ Database Revision Control here:
https://community.checkpoint.com/t5/Policy-Management/R80-Change-Control-A-Visual-Guide/m-p/39702?se...
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