mongodump failing to connection replica set
Try to put &quot;&quot; round --host string... And you don't need --port parameter, because your --host string have port information.
/usr/bin/mongodump -u backup02 -p backup02_password --host &quot;p1dummy:8133,p2dummy:8133,drdummy:8133&quot; --authenticationDatabase admin --out /tmp --db mydbname --ssl --sslAllowInvalidCertificates --excludeCollectionsWithPrefix=system --verbose=5