title: Azure - multiple worker roles - Couldn't store job: Unable to store Job: 'job6', because one already exists with this identification
body: <p>I'm using Quartz.Net scheduler to schedule my jobs. I'm using ADOJOBSTORE to store all these values.</p>
  
  <p>Couldn't store job: Unable to store Job: 'job6', because one already exists with this identification 
  When I try to run it throwing the above error. Any idea?</p>
  
  <pre><code>        ILog log = LogManager.GetLogger(typeof(CronTrigger));
  
          log.Info("------- Initializing -------------------");
  
          // First we must get a reference to a scheduler
          ISchedulerFactory sf = new StdSchedulerFactory();
          IScheduler sched = sf.GetScheduler();
  
          log.Info("------- Initialization Complete --------");
  
          log.Info("------- Scheduling Jobs ----------------");
  
          // jobs can be scheduled before sched.start() has been called
  
  
  
          // job 6 will run every 30 seconds but only on Weekdays (Monday through Friday)
          IJobDetail job = JobBuilder.Create&lt;SimpleJob&gt;()
              .WithIdentity("job6", "group1")
              .Build();
  
          ICronTrigger trigger = (ICronTrigger)TriggerBuilder.Create()
                                       .WithIdentity("trigger6", "group1")
                                       .WithCronSchedule("0,30 * * ? * MON-FRI")
                                       .Build();
  
          DateTimeOffset ft = sched.ScheduleJob(job, trigger);
          log.Info(job.Key + " has been scheduled to run at: " + ft
                   + " and repeat based on expression: "
                   + trigger.CronExpressionString);
  
  
          log.Info("------- Starting Scheduler ----------------");
  
          // All of the jobs have been added to the scheduler, but none of the
          // jobs
          // will run until the scheduler has been started
          sched.Start();
  
          log.Info("------- Started Scheduler -----------------");
  
          //log.Info("------- Waiting five minutes... ------------");
          //try
          //{
          //    // wait five minutes to show jobs
          //    Thread.Sleep(300 * 1000);
          //    // executing...
          //}
          //catch (ThreadInterruptedException)
          //{
          //}
  
          //log.Info("------- Shutting Down ---------------------");
  
          //sched.Shutdown(true);
  
          //log.Info("------- Shutdown Complete -----------------");
  
          SchedulerMetaData metaData = sched.GetMetaData();
          log.Info(string.Format("Executed {0} jobs.", metaData.NumberOfJobsExecuted));
  </code></pre>
  
  <p>Here are my app.config settings</p>
  
  <p>
      </p>
  
  <pre><code>&lt;add key="quartz.scheduler.instanceId" value="AUTO"/&gt;
  &lt;add key="quartz.threadPool.type" value="Quartz.Simpl.SimpleThreadPool, Quartz"/&gt;
  &lt;add key="quartz.threadPool.threadCount" value="10"/&gt;
  &lt;add key="quartz.threadPool.threadPriority" value="2"/&gt;
  
  &lt;add key="quartz.jobStore.misfireThreshold" value="60000"/&gt;
  
  
  &lt;add key="quartz.jobStore.clustered" value="true"/&gt;
  &lt;add key="quartz.jobStore.type" value="Quartz.Impl.AdoJobStore.JobStoreTX, Quartz"/&gt;
  &lt;add key="quartz.jobStore.driverDelegateType" value="Quartz.Impl.AdoJobStore.StdAdoDelegate, Quartz" /&gt;
  &lt;add key="quartz.jobStore.tablePrefix" value="QRTZ_" /&gt;
  &lt;add key="quartz.jobStore.dataSource" value="myDS"/&gt;
  
  &lt;add key="quartz.jobStore.lockHandler.type" value="Quartz.Impl.AdoJobStore.UpdateLockRowSemaphore, Quartz"/&gt;
  &lt;!-- i have modifed for this post --&gt;
  &lt;add key="quartz.dataSource.myDS.connectionString" value="Server=mydatabaseconnectionstring goes here;Trusted_Connection=False;Encrypt=True;"/&gt;
  
  &lt;add key="quartz.dataSource.myDS.provider" value="SqlServer-20"/&gt;
  &lt;add key="quartz.jobStore.useProperties" value="true"/&gt;
  </code></pre>
  
  <p></p>
  
  <p></p>
  
  <h3>Can I do some thing like this... Before adding the job or trigger Check for the record from the database and if not exists add the job?. Is it ok to do this?</h3>
  
  <p></p>
  
  <h3>- or - is it easier to implement Azure Queues to schedule my jobs? Thanks!!</h3>