Release Notes Device Mapper Multipath Enablement Kit for HP StorageWorks Disk Arrays (AA-RWF9B-TE, March 2008)

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Kno wn Issues

Following are the known issues of the HPDM Mu ltipath 4.0.0:

• In SLES OS, the ioctls support is not available on a multipath device created by Device Mapper.

As a result, operations such as SCSI inquiry are not supported with HPDM Multipath devices.

• In RHEL4 and SLES9 hosts, device reset can occur. However does not impact device availability

other than a possible I/O delay. Device reset occurs only during a path failure.

• Paths to the LUNs may go to FAILED state during the LUN transition from one controller to the

other. These paths would be recovered after the polling interval set.

• HP DM Multipath does not provide auto failback feature for the devices presented through iSCSI

initiators. It is recommended to run the following commands to recover the failed paths and

make them available for IO failback:

# /etc/init.d/iscsi restart or # /etc/init.d/open-iscsi restart

# /sbin/multipath –v3

• O n hosts running SLES OS, system may hang during reboot, if device m apper multipath are

conﬁgured on iSCSI devices. To overcome this problem, it is recommended to run the following

command before system reboot:

# /sbin/multipath -F

• Multipath commands may take longer time to execute on heavily loaded servers.

Support

Telephone numbers for worldwide technical suppor t are listed on the HP support website:

ttp://www.hp.com/support/

Collect the following information b efore calling:

• Technical support registration number (if applicable)

• Product serial numbers

• Product model names and numbers

• Applicable error messages

• Operating system type and revision level

• Detailed, speciﬁcquestions

For continuous quality improvement, calls may be recorded or monitored.

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ttp://www.hp.com/go/e-updates

• S ubscribing to this service provides you with e-mail updates on the latest product enhancements,

newer versions of drivers, and ﬁrmware documentation updates as well as instant access to

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• After signing up, you can locate your products by selecting B usin e ss support and then Storage

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