make: generate

conf/example.conf.in

@@ -151,6 +151,26 @@ devices {
 	# This configuration option has an automatic default value.
 	# search_for_devnames = "auto"
 
+	# Configuration option devices/device_ids_refresh.
+	# Find PVs on new devices and update the device IDs in the devices file.
+	# If PVs are restored or moved to a new system with new devices, but
+	# an old system.devices remains with old device IDs, then search for
+	# the PVIDs on new devices and update the device IDs in system.devices.
+	# The original device IDs must also not be found on the new system.
+	# See device_ids_refresh_check for conditions that trigger the refresh.
+	# This configuration option has an automatic default value.
+	# device_ids_refresh = 1
+
+	# Configuration option devices/device_ids_refresh_checks.
+	# Conditions that trigger device_ids_refresh to locate PVIDs on new devices.
+	# product_uuid: refresh if /sys/devices/virtual/dmi/id/product_uuid does not
+	# match the value saved in system.devices.
+	# hostname: refresh if hostname does not match the value saved in system.devices.
+	# (hostname is used if product_uuid is not available.)
+	# Remove values from this list to prevent lvm from using them.
+	# This configuration option has an automatic default value.
+	# device_ids_refresh_checks = [ "product_uuid", "hostname" ]
+
 	# Configuration option devices/filter.
 	# Limit the block devices that are used by LVM commands.
 	# This is a list of regular expressions used to accept or reject block

man/lvmdevices.8_pregen

@@ -97,13 +97,13 @@ will scan devices outside the devices file to locate PVs on renamed
 devices.  A config setting search_for_devnames can be used to control the
 scanning for renamed devname entries.
 .P
-Related to the devices file, the new command option --devices <devnames>
+Related to the devices file, the command option --devices <devnames>
 allows a list of devices to be specified for the command to use,
 overriding the devices file.  The listed devices act as a sort of devices
 file in terms of limiting which devices lvm will see and use.  Devices
 that are not listed will appear to be missing to the lvm command.
 .P
-Multiple devices files can be kept \fI#DEFAULT_SYS_DIR#/devices\fP, which
+Multiple devices files can be kept in \fI#DEFAULT_SYS_DIR#/devices\fP, which
 allows lvm to be used with different sets of devices.  For example, system
 devices do not need to be exposed to a specific application, and the
 application can use lvm on its own devices that are not exposed to the
@@ -139,12 +139,20 @@ Possible device ID types are:
 .br
 .IP \[bu] 2
 .B sys_wwid
-uses the wwid reported by sysfs.  This is the first choice for non-virtual
-devices.
+uses the wwid reported by the wwid sysfs file. This is the first choice.
+.IP \[bu] 2
+.B wwid_naa
+uses the naa wwid decoded from the vpd_pg83 sysfs file.
+.IP \[bu] 2
+.B wwid_eui
+uses the eui wwid decoded from the vpd_pg83 sysfs file.
+.IP \[bu] 2
+.B wwid_t10
+uses the t10 wwid decoded from the vpd_pg83 sysfs file.
 .IP \[bu] 2
 .B sys_serial
-uses the serial number reported by sysfs.  This is the second choice for
-non-virtual devices.
+uses the serial number reported by the serial sysfs file or the vpd_pg80
+file. A serial number is used if no wwid is available.
 .IP \[bu] 2
 .B mpath_uuid
 is used for dm multipath devices, reported by sysfs.
@@ -164,11 +172,27 @@ is used for loop devices, the backing file name repored by sysfs.
 .B devname
 the device name is used if no other type applies.
 .P
-
 The default choice for device ID type can be overridden using lvmdevices
 --addev --deviceidtype <type>.  If the specified type is available for the
 device it will be used, otherwise the device will be added using the type
 that would otherwise be chosen.
+
+.SS Device ID refresh
+.P
+A machine identifier is saved in the devices file, and is used to detect
+when the devices file has been created by a different machine. If the
+devices file was created by a different machine, it indicates that PVs may
+have been copied or restored onto new devices on a new machine. In this
+case, lvm will search for the PVs listed in system.devices on new devices.
+If found, the device IDs will be updated in system.devices for the
+existing PVIDs (assuming the original device IDs are also no longer
+found.)
+.P
+The machine identifier used in system.devices will be either the DMI
+product_uuid from /sys/devices/virtual/dmi/id/product_uuid, or the
+hostname from uname(2). See lvm.conf device_ids_refresh_checks to
+configure this.
+
 .
 .SH USAGE
 .