EMC Storage Product Knowledge Sharing

EMC introduced PowerPath Confgiuration Checker tools for customer. I thought to share about this. It will be very useful for those guys who are using PowerPath as a host fail-over software. It checks existing configuration with EMC support matrix and give you details reports about your configuration whether existing configuration is as EMC support guidelines. This tool is currently available for Windows Operating system.

It tests the following check:

· OS version verification
· Machine Architecture as per ESM(EMC Support Matrix)
· Powerpath Version
· Powerpath eFix
· Powerpath License
· License policy
· I/O timeout
· EOL and EOSL ( End of life and End of Service life)
· HBA Model
· HBA Driver
· HBA Firmware
· Symmetrix Microcode
· Symmetrix Model
· CLARiiON Fail-Over
· CLARiiON Flare Code
· CLARiiON Model
· Veritas DMP Version
· Powermt custom


PowerPath Configuration Checker (PPCC) is a software program that verifies that a host is configured to the hardware and software required for PowerPath multipathing features (failover and load-balancing functions, licensing, and policies)

PPCC can facilitate:
1) Successful PowerPath deployments prior to and after a PowerPath installation.
2) Customer self-service for:
• Planning installations on hosts where PowerPath is not installed.
• Upgrading an existing installation.
• Troubleshooting, for example after configuration changes are made on a host that includes PowerPath, such as the installation of new software

PPCC supports the following user tasks:

Planning — This task applies to a host on which PowerPath has never been installed or is not currently installed. PPCC can identify the software that needs to be installed to support a specific version of PowerPath. For example, PPCC can identify the HBA and driver version that can be installed to support a specific version of PowerPath.

Upgrade — This task applies to a host on which some version of PowerPath is installed. An upgrade (or downgrade) to a different version is required. PPCC can identify components of a configuration that need to change when a different version of PowerPath is to be installed. For example, PPCC can identify the
need to change the Storage OS version.

Diagnostic — This task applies to a host on which some version of PowerPath is installed or on which configuration changes have been made to PowerPath, to the host OS, and/or to other software on the host. This is the PPCC default mode.

For all of the listed tasks, PPCC can identify what changes to make to the PowerPath configuration to ensure continued support for failover and load balancing. Similarly, if PowerPath does not appear to be operating correctly, running EMC Reports and PPCC can assist with configuration problem analysis.

Any disk drive from any manufacturer can exhibit sector read errors due to media defects. This is a known and accepted reality in the disk drive industry, particularly with the high recording densities employed by recent products. These media defects only affect the drive’s ability to read data from a specific sector; they do not indicate general unreliability of the disk drive. The disk drives that EMC purchases from its vendors are within specifications for soft media errors according to the vendors as well as EMC’s own Supply Base Management organization.

Prior to shipment from manufacturing, disk drives have a surface scan operation performed that detects and reallocates any sectors that are defective. This operation is run to reduce the possibility that a disk drive will experience soft media errors in operation. Improper handling after leaving EMC manufacturing can lead to the creation of additional media defects, as can improper drive handling during installation or replacement.

When a disk drive encounters trouble reading data from a sector, the drive will automatically attempt recovery of the data through its various internal methods. Whether or not the drive is eventually successful at reading the sector, the drive will report the event to FLARE. FLARE will in turn log this event as a “Soft Media Error” (event code 820) and will re-allocate the sector to a spare physical location on the drive (this does not affect the logical address of the sector). In the event that the drive was eventually successful at reading the sector, (event coded 820 with sub-code of 22), FLARE will directly write that data into the new physical location. If the correct sector data was not available, (event code 820 with sub-code of 05). There are certain tools from EMC to verify disk and check detail about these Soft Media Errors like sniffer/FBI Tool/SMART Technology etc..