custom timer job is running multiple times in SharePoint 2013

Question

I have created a Web application scoped timer job in SharePoint 2013. This timer job is supposed to be running only once in a month , and should send an email only once . The problem i am facing is this job is running multiple times ,we have 2 WFE servers and it is running from both one by one. I checked several blogs and everyone says to put

(SPJobLockType.job) in the constructor :

  public TimerJob(string jobName, SPWebApplication webapp)
  : base(jobName, webapp, null, SPJobLockType.Job)

  {

            this.Title = "My Timer Job";

  }

which i have already done . the code is as below:

    class TimerJob : SPJobDefinition
    {
        public TimerJob()
            : base()
        {
        }

        public TimerJob(string jobName, SPService service)
            : base(jobName, service, null, SPJobLockType.Job)
        {
            this.Title = "My Timer Job";
        }

        public TimerJob(string jobName, SPWebApplication webapp)
            : base(jobName, webapp, null, SPJobLockType.Job)
        {
            this.Title = "My Timer Job";
        }

        public override void Execute(Guid targetInstanceId)
        {
            UpcomingNotifications.Run();  
        }
    }

Please suggest me something guys that this timer job should not run more than once.

Answer 1

I guess you have missed to set the timer job schedule for your time like below

CustomTimerJob job = new CustomTimerJob(JobName, site);
SPMinuteSchedule schedule = new SPMinuteSchedule();
schedule.BeginSecond = 0;
schedule.EndSecond = 59;
schedule.Interval = 15;
job.Schedule = schedule;
job.Update();    

Job Schedules:

Minute Schedule

Daily Schedule

Monthly Schedule

To know more about SharePoint timer jobs, Click here.

Answer 2

For Multiple Server Environment. Please follow these links.Stackoverflow reference, Martin Hatch Blog

If the above links helps, kindly mark this as answer. Thanks

Answer 3

actually I found out what I was doing wrong. When I was deploying this solution, I was deploying it on the central admin and the web application on which it should run,but for some reason it was getting deployed on all other web applications as well. I went to central admin->monitoring->Job definitions , and disabled the timer job from other web apps and only kept it enabled on the one I wanted it to run and it started working as I wanted i.e only once.

Hope it helps someone having the same issue .