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4.6. Online Device Reconfiguration

When you change your hardware configuration after system bootup and add or delete a device on a node, you may need to update the LVM cache file, which maintains a listing of current LVM devices. For example, when you add new disks to the system on a SAN or hotplug a new disk that is an LVM physical volume, you may need to update this file.
You can update the LVM cache file by running the vgscan command. For information on the vgscan command and the LVM cache file, see Section 5.3.6, “Scanning Disks for Volume Groups to Build the Cache File”.