Promise Pegasus3 - not mounting on Modern Mac?

  • 536 Views
  • Last Post 3 weeks ago
Florentin Constancias posted this 27 May 2025

Dear Promise support,

I’m using a Promise Pegasus3 R8.

Since switching to Apple Silicon Macs, the device hasn’t been functioning properly. I’m currently on an Apple M4 MacBook running macOS 15.3.1 (24D70).

The driver appears to be installed successfully:
systemextensionsctl list | grep pegasus
*    *    268CCUR4WN    com.promise.driverkit.pegasus (21.1.0/1)    com.promise.driverkit.pegasus    [activated enabled]


What’s strange is that when the Pegasus starts up, I can briefly see and navigate the files, but within a few seconds everything freezes, and I get a "Disk Not Ejected Properly" error. This is very frustrating.

The hardware (including cables and drives) works fine, as I’m able to access the files using an older Intel Core i7 Mac running macOS Monterey 12.3.1 — although it only runs in Safe Mode and doesn’t recognize any USB hard drives.

Any support on this issue would be greatly appreciated.

Once this is resolved, I’ll need some guidance on a follow-up problem: after forcefully removing one of the disks out of frustration, I received a “Logical drive set to critical” message. However, I can still access all the data using my old Intel-based MacBook.

 

Thanks for the support,

 

Best,

 

Flo

P.S.: I had posted about this issue before, but I can’t seem to find the thread anymore.


 

Attached Files

Order By: Standard | Latest | Votes
R P posted this 27 May 2025

Hi Florentin,

My best guess is that your Pegasus 3 has very old firmware. Since you have an Intel mac, it's best to check and if necessary update the firmware from the Intel Mac.

Florentin Constancias posted this 28 May 2025

Thanks for your reply. I do think I did that already. Please find enclosed the alllogs attached to the previous message - hope this is what we need to confirm your hypothesis !

 

R P posted this 28 May 2025

Hi,

Please upload a service report. Note, you will have to zip the html file or you won't be able to upload it.

Almost every macOS update causes problems for some users, but Sequoia (15.x) has brought some unusual issues to some few macOS users. That is, for some reason, the Pegasus may only work in some specific thunderbolt port or some few thunderbolt ports, but not all of them. Which port any thunderbolt device is plugged into should not matter, but right now it might. The suggestion is to try different ports and see if you find a port that it works at.

Also, not all docks are created equal, if the ports are labeled 40Gbe with no Thunderbolt near the port, it has not been Thunderbolt certified and may or may not work with any specific device. If you are connecting through a dock, as many do, try connecting the Pegasus directly to the macbook. I have not seen the new M4 macbooks, but I believe they have 3 TB4 ports.

Florentin Constancias posted this 17 June 2025

Hello,

 

Thanks for the support.

Please find enclosed the service report and below some info regarding TB/USB port - I am not using any dock.


Thanks for your help in solving this!

Florentin

Attached Files

R P posted this 18 June 2025

Hi,

PD3 is marked dead and according to the events it was removed while the Pegasus was powered on.

NVRAM| 1113 Jul 23, 2024 18:04:41   Major       PD  3 Physical Disk is marked as DEAD due to removal

But you did mention that you had removed it.

The firmware is up to date. The driver you list is the correct driver.

Some customers reported unusual behavior starting with macOS15.4. This may be the same. After 15.4 some few customers found that their Pegasus would only work from a certain TB4 port. Please try the other ports.

If you are not using the same Thunderbolt cable for the Intel Mac and the M4, it may be a cable issue. If that's the case please try the Intel Thunderbolt cable on M4 and see if that works.

Frank Bosma posted this 19 June 2025

As mentioned above, disk #3 is marked dead due to removal.

The SMART log of this disk also shows no indication of physical damage like re-allocated sectors or events.

In this case you can simply start a rebuild on the 'dead' disk, either via the array or background activities section in the Promise Utility.

Please make sure to unlock the utility in the bottom left corner.

Florentin Constancias posted this 19 June 2025

Thanks for your inputs.

I have just tested the 3 USBc/TB4 ports on my current Apple M4 - OS 15.3.1 (24D70) and I can't mount the drive properly on any of the ports.

I can explore the directories for a few seconds:

and then everything freezes and finaly I have this message after a few minutes.

I had tested it on 3 different silicon Macs and it has been always this issue...

 

In this case you can simply start a rebuild on the 'dead' disk, either via the array or background activities section in the Promise Utility.

Yep thanks but I would like to be able to mount it/ use it on my current computer first !

 

Any other idea or solutions?

 

Best,

 

Florentin

Florentin Constancias posted this 4 weeks ago

Any suggestion? Is it just the something with the Promise Pegasus that will never mount on any modern Mac? 

R P posted this 3 weeks ago

Hi Florentin,

There are 2 possibilities.

1. Bad or intermittent Thunderbolt cable.
2. The Pegasus has a failing power supply.

You can use another Thunderbolt cable to check if it item 1.

If the cable is not the problem, then the power supply is probably the problem. Recently one customer with a similar problem insisted it was not the cable, but eventually reported that the 2 other cables he had tested with were both bad, he had purchased a new cable and that fixed it. 

But if it is not a cable issue, you will need to replace the chassis. The Pegasus chassis is often available used and they have been found in the local computer store, Amazon, EBay and even Google Shopping. There are probably other places that have them.

Be advised that it does not have to be a Pegasus 2 chassis, you can move the RAID set to a Pegasus1/2/3/32 chassis and the volume should mount. For a Pegasus1 or Pegasus2 chassis you will also need a Thunderbolt 2 > Thunderbolt 3 adapter and a Thunderbolt 2 cable.

 

Florentin Constancias posted this 3 weeks ago

Thanks for your message.

Just to clarify, are you certain the issue is hardware-related? Everything works perfectly when I connect the Pegasus to my older Intel Core i7 Mac running macOS Monterey 12.3.1. I can access and copy files without any issues — although it only runs in Safe Mode and I no longer use it regularly.

To me, this suggests that both the cable and the drives are functioning correctly.

What are your thoughts?

Best,

Flo

 

R P posted this 3 weeks ago

Hi Florentin,

You posted this image and a service report.

The thing is, this shows that the Pegasus is not seen on the Thunderbolt port, making generating a service report impossible.

So the information I'm seeing is inconsistent.

Is the Pegasus seen in System Information on one of the Thunderbolt ports?

Florentin Constancias posted this 3 weeks ago

Just to clarify:

-Oder Intel Core i7 Mac running macOS Monterey 12.3.1-> everything works but I don't use this computer anymore.

-Since switching to Apple Silicon Macs, the device hasn’t been functioning properly. I’m currently on an Apple M4 MacBook running macOS 15.3.1 (24D70) but the issue started with à M2 and I had an M3 in between. I have just tested the 3 USBc/TB4 ports, without sucess. I can explore the directories for a few seconds and then everything freezes and finally I get the Disk not ejected properly error.

Best

 

 

Search
Categories
Close