In this case, JCL statement "//SARRECV DD DUMMY" was coded in the CA VIEW SARSTC JCL, for the Recovery file.
The JCL statement is not to be coded, if there is no actual file in use.
As the SARRECV file is written to during the backup cycle; if the //SARRECV statement is coded, then it must point to an existing SARRECV file.
If there is no intention to use the Recovery file, then the //SARRECV DD statement can be commented out (as "//*SARRECV DD ...) - in which case you will see message : -
SARBKT56 NO SARRECV DD STATEMENT - RECOVERY DATASET NOT UPDATED
Note: The message is not informational, but no action needs taken if there is no Recovery file in use.