The problem is in Source or in the Target ?
Oracle Golden Gate 21c in the same host of DBOra12c. I'm with this problem: ERROR OGG-01031 There is a problem in the communication with the Collector/Receiver Service. (Reply received is 'Unable to open file "/u01/app/oracle/product/ogg_src/dirdat/m2000000001" (error 11, Resource temporarily unavailable)').
obs: trails don't arive in target and Lag Since Checkpoint of PUMP process keep increasing.