cvpaths(4) cvpaths(4)
NAME
cvpaths - Xsan File System Disk Discovery Filter
SYNOPSIS
/Library/Preferences/Xsan/cvpaths
DESCRIPTION
The Xsan File System cvpaths file is an optional configuration file
used to control and/or override the normal behavior of scanning system
standard directory locations during the disk discovery phase that
occurs during a cvlabel run, or from the fsmpm at boot/initialization
time.
Normally, the directories scanned look like /dev/disk2, for example.
If a cvpaths file exists in /Library/Preferences/Xsan, then the con-
tents of the cvpaths file will explicitly control which devices and/or
directories will be evaluated during disk discovery. If the cvpaths
file is executable, then it will be executed expecting it to be a shell
script that will produce the cvpaths syntax on standard output, other-
wise it will simply be read as input.
SYNTAX
The format rules for a line in the cvpaths file is:
Any line beginning with "#" is considered a comment line.
Any token beginning with "#" is considered to be a comment up to the
end of the line.
Blank/empty lines are ignored.
A keyword=value syntax is used.
Groups of related keyword phrases can span multiple lines.
Note, the parser capability is limited, and does not allow for any
white space around the equal ("=") operator, although white space, and
commas, are tolerated in all other places.
There are several keywords:
directory=
device=
usage=
hba=
lun=
capacity=
geometry=
verify=
The directory=path directives do not require any of the other keywords.
The directory specified by the directory=path directive will be tra-
versed in a manner similar to the default disk discovery scan mecha-
nism.
A device=path directive begins a group of keywords related to the
device located at path.
for example:
device=/dev/rdsk/c2t39d0s2
would describe exactly one disk/raid device to be scanned during disk
discovery.
The device path is the character special device name.
NOTE! Enumerating specific device paths presumes that the same
disk/raid will always appear in the host system's hard-
ware/device graph with the same exact name.
In most cases, this can only be accomplished by utilizing per-
sistent binding methods related to the specific disk driver
package.
A verify=labelname keyword may be used to verify that the device
located at path contains the Xsan label labelname, for example:
device=/dev/rdsk/c2t39d0s2 verify=CvfsDisk9
The device named must describe a device path that describes the entire
disk.
For example, on Linux systems, you should use /dev/sdc rather than
/dev/sdc1.
Normally, Xsan determines from the raid controller whether a path
should be considered Active, or Passive.
The usage=[Active|Passive] keyword may be used to override the normal
determination of Active or Passive path usage. The default mode is
Active.
The capacity=sectors keyword may be used to override the normal deter-
mination of the number of sectors supported by the device.
The geometry=cyl/tpc/spt/bps keyword may be used to override the normal
determination of the physical geometry of the device where:
cyl is the total # of cylinders
tpc is the # of tracks per cylinder
spt is the # of sectors per track
bps is the # of bytes per sector
Certain device drivers use non-conventional names, or, do not support
standard methods of HBA & LUN identification.
If the device driver name, (e.g. /dev/rdsk/emcpowera1) does not follow
the host system's convention of providing HBA & LUN information, then
the hba=# and lun=# keywords may be used to provide that information.
For example:
device=/dev/emcpower3 verify=CvfsDisk_30 usage=Active hba=6 lun=2
would configure a Linux device driver path externalized as
/dev/emcpower3, assigning the HBA id of 6, and LUN # 2.
This line could also be written as:
device=/dev/emcpower3, verify=CvfsDisk_30, usage=Active, hba=6, lun=2
-or-
device=/dev/emcpower3
verify=CvfsDisk_30,
usage=Active,
hba=6,
lun=2
The HBA id is used by the multi-path code to collect devices together
according to which host HBA is used for access.
The actual value of the number is not critical, what is important is
that all disks/raids configured through a specific host HBA should be
assigned a consistent number that is unique to that host HBA path.
The LUN number is important if the raid controller is one of the con-
trollers recognized by Xsan as capable of Automatic Volume Transfer,
and Active/Passive path declaration. The LUN # is used to index into
specific raid controller mode pages. A Linux example, providing HBA &
LUN information:
device=/dev/emcpowerf hba=4 lun=2 verify=CvfsDisk_30
device=/dev/emcpowerg hba=4 lun=3 verify=CvfsDisk_31
FILES
/Library/Preferences/Xsan/cvpaths
/System/Library/Filesystems/acfs.fs/Contents/examples/cvpaths.example
SEE ALSO
cvfs(1), snfs_config(5), fsm(8), fsmpm(8)
Xsan File System December 2005 cvpaths(4)
Mac OS X 10.9.1 - Generated Fri Jan 10 16:54:15 CST 2014