vdev_id8

Usage

Overview

vdev_id is an udev helper which parses vdev_id.conf(5) to map a physical path in a storage topology to a channel name. The channel name is combined with a disk enclosure slot number to create an alias that reflects the physical location of the drive. This is particularly helpful when it comes to tasks like replacing failed drives. Slot numbers may also be remapped in case the default numbering is unsatisfactory. The drive aliases will be created as symbolic links in /dev/disk/by-vdev.

The currently supported topologies are sas_direct, sas_switch, and scsi. A multipath mode is supported in which dm-mpath devices are handled by examining the first running component disk as reported by the driver. In multipath mode the configuration file should contain a channel definition with the same name for each path to a given enclosure.

vdev_id also supports creating aliases based on existing udev links in the /dev hierarchy using the alias configuration file keyword. See vdev_id.conf(5) for details.

Options

-d device

The device node to classify, like /dev/sda.

-c config_file

Specifies the path to an alternate configuration file. The default is /etc/zfs/vdev_id.conf.

-g sas_direct|sas_switch|scsi

Identifies a physical topology that governs how physical paths are mapped to channels:

sas_direct and scsi

channels are uniquely identified by a PCI slot and HBA port number

sas_switch

channels are uniquely identified by a SAS switch port number

-m

Only handle dm-multipath devices. If specified, examine the first running component disk of a dm-multipath device as provided by the driver to determine the physical path.

-p phys_per_port

Specifies the number of PHY devices associated with a SAS HBA port or SAS switch port. vdev_id internally uses this value to determine which HBA or switch port a device is connected to. The default is 4.

-h

Print a usage summary.