User's Manual

Known Issues and Frequently Asked Questions 93
RAIDCFG Questions
Q: Why does RAIDCFG not give an error message when I use invalid read, write, and cache policies
and/or stripesizes for a particular controller?
A: All RAID controllers have their own default read, write, and cache policies and stripesizes. It is
possible that if you provide an invalid policy or a stripesize for a particular controller, RAIDCFG may not
give an error but will and create the virtual disk with the default policy and/or stripesize.
Q: When I execute RAIDCFG with the RAID level of "01," RAIDCFG creates RAID 1, not RAID 01.
A: This behavior occurs because the RAIDCFG CLI parser ignores zeros preceding any parameter value.
For example,
-r=01 will be parsed as -r=1.
Q: On PowerEdge 1655MC system running embedded Linux, RAIDCFG displays the error: megadev:
Bad file descriptor.
A: Ignore this message. The error message is generated by Megalib because it is trying to open a device
driver that is not present on your system.
Q: What is strict creation?
A: Strict creation is an optional flag that has been added to the create virtual disk command. It allows
you to create virtual disks only if the array disks (that is, hard drives) are within a specified percentage of
disk space of each other.
Q: Why is the drive location of array disks displayed like 0:0:0?
A: The nexus used to display array disks is "channel:target:lun." The Logical Unit Number (LUN) is
always "0." The channel and the target IDs are necessary to identify array disks when dealing with
SCSI devices.
When dealing with SAS devices, the array disk location is displayed as "channel:target:enclosure." It is
possible to have the enclosure value as non-zero. If the enclosure has a non-zero value, then all three
numbers (channel, target, and enclosure) have to be included on the command line.
Q: Do I need to specify RAID type and size when creating virtual disk(s)?
A: No. The default RAID type is RAID 0. If RAID size is not provided, the maximum size allowed for
virtual disk is created. The mandatory fields required to create virtual disks are the controller slot ID and
the array disks.
Q: What is a hotspare (failover drive)?
A: A hotspare is an extra and unused disk drive that is part of an array disk subsystem. A hotspare is
always in standby mode. If a disk failure occurs, the hotspare replaces the failed drive without
interrupting the system.
Q: What is mr2kserv.exe?
A: This is a service needed to configure all LSI RAID controllers in Windows PE. It provides Plug and
Play support.