code: @Override
      protected void doStart() {
          log.info("{}: Starting.", this.traceObjectId);
          this.delayedStartRetry
                  .runAsync(() -> tryStartOnce()
                          .whenComplete((v, ex) -> {
                              if (ex == null) {
                                  // We are done.
                                  notifyDelayedStartComplete(null);
                              } else {
                                  if (Exceptions.unwrap(ex) instanceof DataLogDisabledException) {
                                      // Place the DurableLog in a Started State, but keep trying to restart.
                                      notifyStartComplete(null);
                                  }
                                  throw new CompletionException(ex);
                              }
                          }), this.executor)
                  .exceptionally(this::notifyDelayedStartComplete);
      }
docs: region AbstractService Implementation