On certain servers, consisting of a RAID 5 storage array, there will often be a blinking red light present.  In the absence of an audible alarm, this is usually indicative of what is known as a "hot spare".

This drive is designed to readily be used in the event of another drive's failure, so that the RAID array can continue in an optimal state.

There should be a distinct heartbeat-like blinking pattern similar to the video below.  Also, there should be no other red lights blinking or alarms sounding.

 Another way to confirm that the drive is indeed a hot spare is to login to the MegaRAID application.  You should see a screen similar to the following that denotes a Slot reserved as a hot spare.

In the event you do have an alarm sounding or an irregular blinking red light on the server, please contact SnapStream support (support@snapstream.com or 877-696-3674) to assist with determining the cause, as this can possibly indicate an issue with the storage array.