MPIO RDAC IBM SAN STORAGE DS4700 ?

Hello,

I have AIX 6.1 with TL 4 and it is connected to IBM SAN STORAGE DS4700

After assigning some disks from SAN to AIX, I can see the disks in my AIX as

But it should show IBM MPIO DS4700 Array Disk

Where can I download the drivers for MPIO or RDAC ? will it be RDAC or sddpcm ?

AIX MPIO and SDDPCM multipath options with DS3000/DS4000/DS5000 ���������� - ��־ - wolfsun - ��ԴSNS - Powered by UCenter Home

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i read somewhere
Multipath I/O (MPIO) In AIX Version 6.1, the DS4K products are configured as Multipath I/O (MPIO) devices by default. A DS4K product using the FCPARRAY driver may be migrated to the MPIO driver by using the following instructions, or all DS4K devices may be migrated by uninstalling the devices.fcp.disk.array.rte package and then running the cfgmgr command or rebooting. The DS3K products are always configured as MPIO devices. There is no FCPARRAY support for these devices. The MPIO support for these devices removes the limitation of connecting only one adapter to each DS3/4K controller port.
http://publib.boulder.ibm.com/infocenter/aix/v6r1/topic/com.ibm.aix.resources/RELNOTES/SC23662903.pdf

so does this mean i have to uninstall devices.fcp.disk.array.rte to configure MPIO ?

ChatGPT Responds to a 14 Year Old Unanswered Question

Based on the situation you're describing, you are using an AIX 6.1 system connected to an IBM DS4700 SAN storage array, and the disk devices are currently listed as MPIO Other DS4K Array Disk instead of IBM MPIO DS4700 Array Disk. This implies that AIX's default configuration might not be fully optimized for DS4700, which could be due to driver issues.

MPIO vs. RDAC

AIX 6.1 supports MPIO (Multipath I/O) by default for many storage systems, including DS4700. The RDAC (Redundant Disk Array Controller) was previously used in older configurations, but in more recent versions of AIX, it has been largely replaced by MPIO or SDDPCM (Subsystem Device Driver Path Control Module).

Key Points:

• MPIO is the default multipathing solution for AIX 6.1 and is usually recommended for IBM DS4K series.
• SDDPCM is an alternative path control module often used with IBM SAN devices and may be required for optimal performance.
• RDAC has become outdated for newer AIX configurations and storage systems like DS4700.

Next Steps:

1. Check Installed Drivers:
   To determine if you have the correct drivers installed for MPIO or RDAC, you can check your installed packages:

   lslpp -l | grep -i devices.fcp.disk.array.rte
   

   If the devices.fcp.disk.array.rte package is installed, it's possible that it's still configuring the disks using the old RDAC method.

2. Uninstall RDAC:
   If you're using the RDAC drivers, you may need to uninstall the devices.fcp.disk.array.rte package. To uninstall it:

   smitty remove
   

   Search for the devices.fcp.disk.array.rte package and remove it. After uninstalling, run cfgmgr to reconfigure the devices:

   cfgmgr
   

3. SDDPCM or MPIO:
   If you plan to use SDDPCM for improved path management with DS4700, you'll need to ensure it's installed. To check for SDDPCM:

   lslpp -l | grep -i sddpcm
   

   If not installed, you can download the SDDPCM driver from IBM Fix Central. Follow the steps:

   • Go to IBM Fix Central.
   • Search for SDDPCM for your specific version of AIX and DS4700.
   • Download and install it using smitty installp.

4. MPIO Configuration:
   To ensure that MPIO is correctly configured for your DS4700 array, verify the MPIO settings for each disk using:

   lsattr -El hdiskX
   

   You should see the MPIO settings listed. If the disks are correctly using IBM MPIO, the type should reflect IBM MPIO DS4700 Array Disk. If not, the reconfiguration process via cfgmgr after uninstalling RDAC should correct it.

Conclusion:

• It is likely that you will need to uninstall the devices.fcp.disk.array.rte package if RDAC is still in place.
• Download and install SDDPCM if you need advanced path management, or stick with AIX's built-in MPIO which supports DS4700 by default in AIX 6.1.