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The formal syntax of the vols option follows.
vols = volume-specification
volume-specification ::== all-volumes | volume-list | ''
all-volumes ::== 'all' [ ':' policy ] [ space 'except' space device-list ]
device-list ::== device [ space device [ ... ] ]
device ::== Linux-device-path
space ::== space or Tab character and not the word space
policy ::== 'k'
The recommended setting is vols = all, which enables DX Storage to use all volumes except
the USB flash drive. In addition, vols = all:
• Works with single server and multi-server configurations.
• Supports exceptions, as discussed in Section 6.5.3, “Specifying Exceptions”.
• Supports :k (keep), which is discussed in Section 6.5.2, “policy”.
Following are examples of vols entries.
vols = all
vols = all:k
vols = all except /dev/hda
vols = /dev/sda /dev/sdb
vols = /dev/hda:k /dev/hdc:k
If no value is set for vols or if it is absent, the DX Storage node is referred to as volumeless. A
volumeless node is able to process client requests and can be used, for example, with a few nodes
that have fixed IP addresses to serve as stable primary access nodes for all client operations.
The device component is either the keyword all or the Linux device path string for the drive.
When the keyword all is used, do not include any other device path specifications.
Dell strongly recommends you use vols = all and discourages you from using Linux device
paths. You can optionally exclude certain volumes from being used by DX Storage as discussed in
Section 6.5.3, “Specifying Exceptions”.
Examples of a Linux device path are:
Older IDE disks, also known as Parallel ATA, EIDE, ATA-33, ATA-66, ATA-100, or ATA-133,
use the “hd” device names. These drives are configured as master or slave devices on each IDE
controller. Typically, the master devices will be /dev/hda and /dev/hdc, while the slave devices will
be /dev/hdb and /dev/hdd.
SCSI, SAS, and SATA disks typically use the “sd” device names. The device letters are assigned
sequentially in the order in which the drives are discovered starting at /dev/sda. The hardware report
in the utility menu will show the actual names in use on a node.