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Old Jan 10, 2013, 09:33 PM   #26
flynz4
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Originally Posted by hfg View Post
Is there some setting you have to set from a configuration console to get a bootable J4?

Mine doesn't boot OS X, probably because the driver isn't installed at that point and it doesn't provide a "bios" to inject one into the initial system. I notice that the blue "disk icons" on the front panel are not lit until I actually log-in to OS X, so they are in my personal environment (I may look into trying to move that process to the basic OS X system level so all logins will have access to the drive system). I notice that it also goes to sleep when the iMac does, shutting down into a standby mode.

I don't need it to be bootable, but I thought it would be nice to have that capability for emergency booting if something were to happen to the internal boot drive (but I always keep a bootable portable drive in my desk for such occasions).

I had originally ordered the R4, but changed my mind minutes after I pressed the button and cancelled and ordered the J4 instead. I am really glad I did that. The J4 will give me much more flexibility to mix and match drives and configurations and be much more than just a big disk like the R4. It is also way smaller, quieter, and easier to integrate into the iMac "minimalist" desktop environment.

It is actually like my old Mac Pro with the 4 drive bays that I could configure as I desired.


-howard
Howard,

I am not too sure I understand your comment (bold above). I believe the J4 only supports RAID 0,1,5. The R4/R6 supports RAID 0,1,5,6,10.

With the R4... you first map physical drives into one or more logical drives. Then you select the RAID level for the logical drives. Hence... the R4 supports JBOD by allowing multiple logical drives.

I agree with the smaller/minimalist comments.

/Jim
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Old Jan 10, 2013, 11:25 PM   #27
hfg
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Originally Posted by flynz4 View Post
Howard,

I am not too sure I understand your comment (bold above). I believe the J4 only supports RAID 0,1,5. The R4/R6 supports RAID 0,1,5,6,10.

With the R4... you first map physical drives into one or more logical drives. Then you select the RAID level for the logical drives. Hence... the R4 supports JBOD by allowing multiple logical drives.

I agree with the smaller/minimalist comments.

/Jim
Hi Jim,

I agree that the R4/R6 is a very powerful disk storage system and has a very sophisticated management scheme to allow diversified configurations. But, I fail to see, even after reading the manual, how it gives you a true JBOD setup with discrete access to each individual physical disk. It has all the popular RAID configurations using hardware RAID controllers vs. the J4 which uses Apple Software Raid and thus only supports RAID 0, 1, 5 plus the ability to use the disks individually or concatenate (span) several drives into a larger contiguous drive (flavors of physical JBOD). I could probably even create a "Fusion" drive with 2 of the drive bays containing a SSS and a Hard Disk, then span the other 2 hard disks into a single non-striped 2TB drive.

Perhaps I didn't study deep enough on the R4, so please correct me if I am misunderstanding the specifications of the R4/R6.

Thanks,
-howard
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Old Jan 11, 2013, 02:26 AM   #28
flynz4
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Originally Posted by hfg View Post
Hi Jim,

I agree that the R4/R6 is a very powerful disk storage system and has a very sophisticated management scheme to allow diversified configurations. But, I fail to see, even after reading the manual, how it gives you a true JBOD setup with discrete access to each individual physical disk. It has all the popular RAID configurations using hardware RAID controllers vs. the J4 which uses Apple Software Raid and thus only supports RAID 0, 1, 5 plus the ability to use the disks individually or concatenate (span) several drives into a larger contiguous drive (flavors of physical JBOD). I could probably even create a "Fusion" drive with 2 of the drive bays containing a SSS and a Hard Disk, then span the other 2 hard disks into a single non-striped 2TB drive.

Perhaps I didn't study deep enough on the R4, so please correct me if I am misunderstanding the specifications of the R4/R6.

Thanks,
-howard
Howard,

To be honest... I originally used my 8TB R4 as a 4-drive 6 TB RAID-5 (out of the box)... and then later reconfigured it to be a 4-drive 4TB RAID-10. I have never tried any JBOD modes.

From what I understand:

1) You have 4 physical drives with the R4 (6 with the R6).
2) You can map any subset of physical drives... to logical drives.
3) As you create one or more logical drives... then you can format those... and they show up as distinct drives... that you can use independently (i.e.: JBOD)
4) If a logical drive only has a single physical drive... then it is an independent drive. You can have as many of these as you have physical drives
5) If a logical drive has two or more physical drives... then you apply RAID to that logical drive

As I said... that is not how I use mine... but it seems to me that you could do JBOD if you choose.

Personally, I am using RAID-10 which gives me 4TB of striped + mirrored usage. It is not the most efficient way of using the capacity... but for me, 4TB is more than enough... so I get the benefits of mirroring... plus resiliency to at least one drive failure (possibly two depending on which two).

BTW: The J4 does look like a nice device too. I might consider picking up 4 SSDs, and using a J4 to configure them in RAID 0 or 1. It would be a fun experiment.

/Jim

Last edited by flynz4; Jan 11, 2013 at 02:32 AM.
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Old Jan 11, 2013, 12:06 PM   #29
hfg
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Originally Posted by flynz4 View Post
Howard,

To be honest... I originally used my 8TB R4 as a 4-drive 6 TB RAID-5 (out of the box)... and then later reconfigured it to be a 4-drive 4TB RAID-10. I have never tried any JBOD modes.

From what I understand:

1) You have 4 physical drives with the R4 (6 with the R6).
2) You can map any subset of physical drives... to logical drives.
3) As you create one or more logical drives... then you can format those... and they show up as distinct drives... that you can use independently (i.e.: JBOD)
4) If a logical drive only has a single physical drive... then it is an independent drive. You can have as many of these as you have physical drives
5) If a logical drive has two or more physical drives... then you apply RAID to that logical drive

As I said... that is not how I use mine... but it seems to me that you could do JBOD if you choose.

Personally, I am using RAID-10 which gives me 4TB of striped + mirrored usage. It is not the most efficient way of using the capacity... but for me, 4TB is more than enough... so I get the benefits of mirroring... plus resiliency to at least one drive failure (possibly two depending on which two).

BTW: The J4 does look like a nice device too. I might consider picking up 4 SSDs, and using a J4 to configure them in RAID 0 or 1. It would be a fun experiment.

/Jim
Thanks for the information Jim, that was helpful.

I wish I had access to 4 ea. identical SSDs to try a quad SSD RAID-0 on the Pegasus J4 to see what it can do for speed.

-howard
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Old Jan 11, 2013, 06:10 PM   #30
hfg
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Originally Posted by TigerClaw27 View Post
When you had it apart you didn't happen to notice what chips/chipsets Promise is using in these? I wonder if its a Thunderbolt to PCIe and PCIe based SATA controller setup like we've seen on many of the other solutions.
I haven't had a chance to disassemble my Pegasus J4, but I did notice this in the manual specifications:

Processors:
NXP ARM-based LPC1114 (system monitor and power management function)
LSI SAS 2004 with PowerPC 440 Core (PCIe to 4 port, SATA/SAS controller)


-howard
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Old Jan 17, 2013, 09:18 AM   #31
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Is there an enclosure for 3.5" drives? I am looking to put 2 or 4 3.5" drives in the same thunderbolt enclosure in this configuration.

Drive 1 : Media
Drive 2 : Time machine backup
Drive 3 : Media Backup
Drive 4: HDD clone of my iMac.
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Old Jan 17, 2013, 09:50 AM   #32
xgman
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I am having good luck with the Western Digital MyBook Duo Thunderbolt enclosures. Only problem is you have to take them with their drives and then substitute your own, so pricier than need be unless you are in the market for a couple of Velociraptors. Anyway, once setup, you can mix and match any drives you wish.
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Old Jan 23, 2013, 02:15 PM   #33
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Originally Posted by stanw View Post
I want to place some harddrives into an enclosure that I can connect to my Mac via Thunderbolt. I do not want the drives in the enclosure to behave as a RAID, but rather I want the drives in the enclosure to show up individually on my desktop as separate drives so I can have access to lots of drives that I can swap in and out of the enclosure.

Is there a device that will do this?

Thanks.
There is lots of companies call BIG/SPAN as JBOD - Dont know why.

For JBOD (multiple drives) the best solution is get a Port Multiplier box (4 or 5 drives) then get the USB3.0 to eSATA adapter.
http://www.amazon.com/Adapter-Suppor.../dp/B005DCCMII

Then you would see ALL individual drives 0 with drivers or software to install.

Thank you for the users review in AMAZON. I bough one and use it with my five bay port multiplier very happy with it
I can transfer 90+MB/s with this solution, and cost me only 30's dollar instead 100's of dollars with TB

Hope this help you to save some $$

Last edited by FireWire2; Jan 23, 2013 at 02:17 PM. Reason: Spelling
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