Hi.   For further troubleshooting I recommend following those guides here:   PowerEdge HDD: How to identify a HDD failure and to solve the issue?[URL]   Diagnostic tools for advanced troubleshooting on PowerEdge servers [URL]   Gathering logs for advanced troubleshooting on PowerEdge servers [URL]   Especially a Controller Log (tty) will be very beneficial. If you could upload it and make it available for us, we could take a look.   Are those disks Dell-certified discs?   And what system do you own/use?   Best regards,Stefan  
A few weeks ago we spotted that one of the hard disks in a RAID1 array on this controller was faulty, and so I removed that hard disk and put in another disk. The array rebuilt successfully. Because both the original disks were coming up to 8 years old I decided that it would be prudent to then replace the "other" disk in this array, resulting in a fully rebuilt array on two new disks. The second replacement disk went in okay however now that second disk is saying "failure predicted". I plan to raise the with the disk supplier however I was wondering might this be a red herring? I have not rebooted between disk replacements. How can I determine WHY failure is predicted? H700:  
H700 RAID1 Swapped Both Drives Now Failure Predicted