@WayneUong are you sure you are using littledata:synced-cron and not percolatestudio:synced-cron? There's been a migration at some point and percolatestudio:synced-cron is not maintained anymore. Seems like you're encountering the issue solved by #135

@TheGame2500 I use littledata:synced-cron. I did a quick test to confirm:

if (Meteor.isServer) {
    SyncedCron.add({
        name: 'Test',
        schedule: function (parser) {
            return parser.text('every 5 seconds');
        },
        job: function () {
            console.log('start');
            Meteor._sleepForMs(9999999);
            console.log('end')
        }
    });

    Meteor.startup(() => SyncedCron.start());
}

I have the first server running, let the cron job starts, then start the 2nd server, sharing the same db using MONGO_URL=mongodb://localhost:3001/meteor meteor --port 3002

The result is that the 2nd server starts the same job while the 1st is still not done. Meteor._sleepForMs(9999999); is to simulate a long running cron job.

@TheGame2500 Can you reproduce it?