HPM-XA and HPM-XU FAQ

5 Port Hardware Port Multiplier (HPM-XA and HPM-XU)

Q: What kind of RAID is supported?

A: The HPM-XA and –XU support individual drives (JBOD), RAID levels 0, 1, 10, 3 and 5. They also offer a Clone mode (similar to RAID 1 with more than 2 drives) and Large mode (concatenated space).

Q: I’ve connected two or more drives to the PM and the PM is connected to my computer on eSATA. Why am I only able to see one drive on the computer?

A: There are two causes:

First, if the drives are configured as a RAID, they will appear as only one physical unit. It will identify itself to the operating system with the manufacturer name “Addonics” and the model number matching the type of array (such as “Addonics RAID 5,” “Addonics Clone, etc.). This is normal behavior.

Second, if the drives are configured as JBOD and only one can be seen by the operating system, then either the host adapter, driver, or the operating system itself is not supporting the port multiplier technology. Consult the SATA controller’s manufacturer if you are unsure, and take note that port multiplier support is a rare feature in most motherboard controllers. Addonics offers a wide selection of port multiplier compatible controllers.

Q: Does the Port Multiplier support hot swapping?

A: The Port Multiplier does support hot swapping, although the SATA controller it’s connected to may not. Hot swapping is also a feature not commonly found in most SATA controllers. Check with the controller’s manufacturer if you are unsure.

As a RAID array, the Port Multiplier still depends on hot swapping support if it is disconnected from or reconnected to the host adapter; however, the individual drives may be hot swapped during maintenance without disturbing the connection to the host.

Q: When the Port Multiplier is connected to a Marvell 9xxx series host (like the Addonics AD2SA6GPX1), the JMicron RAID Manager works only sporadically and is very slow to detect the Port Multiplier, drives connected to it, and any changes. Can this be fixed?

A: A compatibility issue has recently been identified between the Marvell 9xxx driver and the HPM-XA and –XU units. Although the array or JBOD itself will function correctly, the Marvell driver seems to interfere with the JMicron RAID Manager’s communications with the Port Multiplier. If you are running Windows 7, you may be able to safely uninstall the Marvell driver, making sure to check the checkbox for “Delete the driver software for this device.” Windows will then identify the controller as a “Standard AHCI 1.0 Serial ATA Controller” in the “IDE ATA/ATAPI controllers” category of the Device Manager. In this condition, the AD2SA6GPX1 has been fully tested and confirmed to support port multiplier-based JBOD and hot swapping, as well as restoring full operability to the JMicron RAID Manager. Take extreme caution if the Windows system drive is connected to the same controller – it may be preferable to leave this issue in place rather than risk causing Windows boot failures.

Q: How do I set up a spare drive for my RAID array?

A: From the JMicron RAID manager, simply declare the specific drives desired as a RAID, and the remaining drive will remain blank and is considered a spare. When using the dipswitch configuration, install only the desired drives first, set up the RAID array, then add a fresh, blank drive later.

Q: How do I set up the RAID volume created by the Port Multiplier as a boot drive?

A: Once the RAID has been configured, your system BIOS should show a SATA unit connected called ADDONICS for the manufacturer and the raid type for the model number (ADDONICS RAID5, ADDONICS BIG, etc.). Treat this the same way as any individual drive, place it correctly in the boot order, install the operating system to it, and it will be bootable.

Q: Why does the RAID rebuild itself every time when I reboot my system?

A: If the array previously experienced a severe error or a drive has recently been replaced, the unit may take a long time to rebuild. If it is turned off during the rebuild process, the rebuild process will start over once power is restored.  If the problem persists after confirming the rebuild has completed, one of the drives on the array may be having a problem that is not a solid failure.

Q: Does the Port Multiplier slow down the performance of the hard drive since five drives are all connected to the system via one SATA port?

A: The switching capabilities of the Port Multipliers are extremely efficient and I/O performance should be generally unaffected, and reduction of performance shouldn’t be perceptibly different than creating identical circumstances with individual SATA ports. For RAID configurations, some will show negligible performance differences under normal conditions (not degraded or rebuilding), and in some cases a performance boost can be measured.