Attempts to execute a test schedule from IBM Rational Performance Tester (RPT) results in the error "RPT is unable to execute a schedule because one of the ports(7080) failing to open a second instance of RPT workbench for a different workspace."
The full error message is as follows:
Error : "RPT is unable to execute a schedule because one of the ports(7080) it uses to communicate with the agents has been taken by another RPT (or other server) process. Ensure only one RPT instance is running. Check Agents Failed."
Implementation of Majordomo service in RPT 8.3 is the reason for this error.
The changes from RPT 8.2 to 8.3 is the implementation of Majordomo service. This service allows any agent controller connect to any number of workbench machine without making any changes from the firewall on respective agents. This was a requirement in prior versions.
The workbench acts as a server to the agents starting from 8.3; hence, opening two different instances from the same machine does not work the same as in 8.2.x version.
Resolving the problem
Configure a second port using the option from RPT GUI :
Look from RPT menu for Windows > Preferences > Test > Server