Dead disk... help !

  • Last Post 20 September 2023
gere arnaud posted this 19 March 2019


I work with 2 Pegasus in RAID5 (Pegasus R4 and Pegasus 2 R6).
my Pegasus R4 has a dead drive since yesterday.
Is it possible to temporarily empty the R4 and then reconfigure it into RAID5 on
3 physical disks instead of 4?
Indeed, given the age of this system, I do not think replace the dead disk. Thank you in advance for your feedback, I'm afraid of losing very important data ...


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Nick Kay posted this 20 September 2023

RP Thank you for this!  I just had a horrible situation happen, but now I can at least get the data off and start over.  <3

R P posted this 04 February 2020

Please note that you can force a drive marked dead online from promisutil.

phydrv -a online -p 2

This example is for PD2, change the PD number to the appropriate drive.

If you accidentally pulled the drive you know it has not failed, but if the drive was giving errors, you may need to replace the drive.

neseik mikein posted this 04 February 2020

Thanks for the help. It really helped me.

Jan Marcelis posted this 12 April 2019

Ha Gere,


Had the problem last week to. Also RAID 5 using 5 disks. I also accidentaly removed one disk when the systen was swithced on.

I solved the problem by:

At first stay of all your other disk from now on!!!!!!

shut down the Promise system

Remove the dead disk. Remove the disk from the slide (4 mounts see manual)

Format the disk on an external disk system (in the Netherlands about 35 Euro). You cannot use the Promise box because he regognises the disk as dead. But dont forget also to renew the partition on the disk. Just formatting is not emough.  Promise recognised my disk still after simple formatting. This is also the point were you can see wethher the disk is still usable, In my case the disk was still OK.

After the new partioning and formatting The disk is seen as a new disk by promise. put ik back in the slide en put in in de promise system.

now in the utility App ; make from the disk an " unconfigured" one. An than in the utility App "rebuild" and he will use the formated disk for rebuilding your RAID.

At least it did so in my case. I sleep well after soving this problem, I can tell you.




Raghuraman Kannan posted this 27 March 2019

Hi Gere,

Please move the current version of the Utility to trash and install it from the below link

You should be able to run the commands through Terminal then.

Thanks !

gere arnaud posted this 25 March 2019

the command promiseutil is not found in mac terminal...

arunkumar b posted this 21 March 2019

Please try save report from terminal.Open MAC terminal and then type promiseutil and then type the following commands one at a time and save the output of the commands to a file and attach that file to this case id for review.You could also contact support @ +1 (408) 228-1500 for further assistance

subsys -v

enclosure -v

ctrl -v

phydrv -v

array -v

logdrv -v

smart -v  


event -l nvram

Note:- In the above command " event -l nvram " it is lower case letter 'l' but not a numeric 1.





gere arnaud posted this 20 March 2019

First of all, thank you for this detailed answer.
Unfortunately, I can not get a report service.
Either no file is created, or I do not know where it is saved ... When I click on the button, no window appears

arunkumar b posted this 20 March 2019

Hi Gere,

Yes,you could delete disk array and recreate RAID 5 with three physical disk and leaving the other slot empty.Make sure to backup the data before deleting array.Please go to the link below to check our KB article on how to create a new Disk Array and the Logical Drive.

Also drives could be marked as dead due to many possible reasons, accidentally removing drive when unit is turned on , power outage or drive encountered bad errors.We could rebuild the dead drive ,if there is no error in the drive.In order to find the exact problem please open case in and  attach the latest subsystem report.

Steps to save the subsystem report :

1) Open Promise Utility.

2) Click subsystem information icon on the top of the window.

3) Click the lock symbol on the left bottom corner of the screen to unlock the utility.

4) Click on save service report button to save the subsystem report and attach it to this case.