We have a client that does quite a bit of production work. They have a very robust Promise RAID setup (2 x R4 and 1x R6) with over 30TBs of storage. We recently ran into an issue with the drives in the R6 showing up as Dead/Offline. After some back and forth with Promise tech support and conducting our own research we found a rather simple solution. I wanted to document our solution in an effort to save you some time if you encounter this issue.

Pegasus2 R4 Promise Utility For Mac Rebuild Raid Kit
Pegasus2 R4 Promise Utility For Mac Rebuild Raid Kit
Pegasus2 R4 Promise Utility For Mac Rebuild Raiders
Pegasus2 R4 Promise Utility For Mac Rebuild Raid Software

In a few hours the Pegasus will totally rebuild that blown drives information. This of course happens while the drive array is STILL IN USE, which is great for a network or a computer that must be running at all times. The Pegasus arrives formatted and configured in a RAID 5 array, but you may change that to RAID 1, 2, 6, or 10 if you wish. One of just a few options for Mac-formatted external RAID arrays, the Promise Pegasus3 R4 is a good choice if you need to store mountains of data and access it quickly.

After a rather serious Florida Summertime storm all the drives on an R6 were showing up offline. Being that this was setup as a RAID 5 this posed some potential data loss. Thankfully, this RAID was the clients versioned backup so worse case we replace the drives and reclone from the working RAID. I still found it highly suspect that 6 drives would have failed so I ran a subsystem report and sent it off to Promise's tech support. Within an hour I receive a response recommending that we upgrade the firmware and see if that resolves the issue. We proceeded to upgrade the firmware on the R6 by doing the following:

Click on Promise utility on the Menu Bar -> Check for updates. - It would prompt for updating the firmware, update the firmware. - After the update, click on subsystem information on the Promise Utility window -> Shutdown/Reboot. - Choose reboot & restart the unit.

Jul 31, 2013 If Pegasus Manual could be that clear and simple! I know technology, but frankly, after reading the manual almost from cover to cover, I couldn’t even get to activate the greyed Rebuild button frustrating. Now rebuilding a failed 3TB drive in a pegasus R4 RAID5 thanks to you. Smile coming back.

After the unit rebooted the drives were still showing offline. I then started to do a bit more research and come to find out that others have experienced the logical drive of the Promise RAID going offline after abruptly losing power. The issue was resolved by forcing the drives back online. Unfortunately, the option to force the drives online isn't available through the Promise Utility GUI but has to be done via the Terminal application. See below for instructions on forcing the drives back online.

On the Mac, open the Terminal app and run:

This will open the Promise Utility. Now type the following:

Pegasus2 R4 Promise Utility For Mac Rebuild Raid Kit

If you have the R6 you will need to add the following commands in order to force drives 5 & 6 online -

After you force the drives online reboot the RAID and you should be good to go.

PROMISE Technology Inc. posted this 13 December 2017 - Last edited 14 December 2017

Table of Contents
Section I. Identifying the Pegasus Model and Specifications
A. Pegasus3 Models
B. Pegasus2 Models

Section II. Creating Disk Array and Logical Drive
A. Example with macOS
B. Example with macOS with APFS
C. Example with Windows

Description: This article will illustrate to all Pegasus customers on how to configure a Pegasus from scratch.

Section I. Identifying the Pegasus Model and Specifications
Note: Review the tables below indicating which RAID levels each Pegasus Model supports.
A. Pegasus3 Models

Pegasus3 Specifications Table

Model	Pegasus3 R4	Pegasus3 R6	Pegasus3 R8
Form Factor	4-Bay Hardware RAID Enclosure	6-Bay Hardware RAID Enclosure	8-Bay Hardware RAID Enclosure
Interface	2x Thunderbolt™ 3 Technology Ports (40Gbps)
OS Support	macOS 10.12 and macOS 10.13 Windows 7, Windows 10
RAID Levels	0,1,5,6,10	0,1,5,6,10,50	0,1,5,6,10,50,60

For the full specifications table for the Pegasus3 Series, please download the datasheet.

B. Pegasus2 Models

Pegasus2 Specifications Table

Model	Pegasus2 R4	Pegasus2 R6	Pegasus3 R8
Form Factor	4-Bay Hardware RAID Enclosure	6-Bay Hardware RAID Enclosure	8-Bay Hardware RAID Enclosure
Interface	2x Thunderbolt™ 2 Technology Ports (20Gbps)
OS Support	Mac OS X 10.8.5 or higher macOS 10.12 and 10.13 Windows 7, Windows 10
RAID Levels	0,1,5,6,10	0,1,5,6,10,50	0,1,5,6,10,50,60

For the full specifications table for the Pegasus2 Series, please download the datasheet.

Section II. Creating Disk Array and Logical Drive
A. Example with macOS

Open the Promise Pegasus Utility.
Unlock the Utility by click in on the lock icon
In order to make any changes to the Pegasus, the utility must be unlocked
Click on the Physical Drive icon to get the list of the disks.
You want to ensure that all the drives (or the drives that you want to use for your new array) have a Configuration Status as Unconfigured:
Once you've verified that all the drives have a Configuration Status of Unconfigured, proceed to the Disk Array icon. There should be no configured disk arrays in the subsystem.
Click on Create Disk Array
You will be brought to the Disk Array sub-menu.
A. Input the Alias label (i.e. MyArray01)
B. Ensure that Media Patrol and PDM (Predictive Data Migration) are enabled.
C. Media Type will be Hard Disk Drive for non-SSD SATA drives.
Select the drives you will allocate to the array. In this example, all (8) drives are being used in this illustration.
Device in Example: Pegasus3 R8
Click Submit and you will receive a message that the disk array was created successfully.
A. Click Finish
You will be presented back to the Disk Array menu with the Status of your Disk Array.
Click on the Logical Drive icon.
A. Click on Create Logical Drive.
In the Logical Drive sub-menu, locate the array you created on step 10.
A. Ensure the radio button is selected next to the array that you will use to configure the Logical Drive.
B. Once confirmed, click Next.
You will be presented with the Create Logical Drive sub-menu. In this screen you will be able to dictate the settings for your Logical Drive.
Note