How to fix the Oracle error PGA-21301: invalid control received: string?

In this post, you’ll learn more about the Oracle ErrorPGA-21301: invalid control received: string with the details on why you receive this error and the possible solution to fix it.

Oracle Error Description

PGA-21301: invalid control received: string

Reason for the Error PGA-21301: invalid control received: string

Cause: The RRM received an invalid control flag from a partner RRM.

How to fix the Error PGA-21301: invalid control received: string ?

You can fix this error in Oracle by following the below steps

Action: This error indicates that there may be a problem on the partner LU side of the connection. Corrective action must be taken by the system administrator for that LU.