The Customer ID (CUSTID) identifies a specific license pool. Also referred to as a Pool ID.
An organization may have multiple license pools, each with its own CTL file and corresponding Customer ID.
The Customer ID is displayed on the line beginning with:
CUSTID
The same Customer ID is also referenced in the corresponding package definition within the license.dat file.
CTL file:
CUSTID 12345
license.dat file:
PACKAGE <package_name> ... CUSTID=12345
The Customer ID in the CTL file and the corresponding package in the license.dat file must match.