Schedule Cron expression not valid?

Question

I'm creating an AWS CloudWatch rule, using the Schedule Cron expression: 30 10 * * 2,5 *, namely - every Tuesday and Friday on 10:30 UTC.

However, AWS gives me

There was an error while saving rule Snapshot_EBS_disk.
Details: Parameter ScheduleExpression is not valid..

Any idea what's wrong with my expression?

Answer 1

One of day-of-month or day-of-week must be ?. So to make your cron expression valid you would use the following:

30 10 ? * 3,6 *

Also note that Tuesday and Friday are 3 and 6 respectively