Hi @Shi, Quan ,
Thanks for posting your query on Microsoft Q&A platform.
Timeout property mentions the duration of time the pipeline waits for the activities to finish. Once the timeout duration is reached, pipeline throws timeout error. For example for few activities we know it might not take more than 10 hrs. In that case we can set the timeout to be 10 hr.
Retry mentions no. of times a failed activity can rerun by itself without someone triggering the pipeline. This is helpful when an activity fails due to intermittent connectivity issues and on retry, it might run successfully without manual intervention.
In case of retry, we need to mention in what interval we need to retry. That's mentioned in retry interval. In the above connectivity example, we can set the timeout interval to be 10 minutes. This means, upon first failure, the pipeline waits for 10 minutes before retrying the activity again.
Please check this link for understanding. (From MS documentation page)
Thanks. Please revert for more details.