System information

In most cases, fully resizing an online logical unit involves two things: resizing the logical unit itself
and reflecting the size change in the corresponding multipath device (if multipathing is enabled on
the system).
To resize the online logical unit, start by modifying the logical unit size through the array
management interface of your storage device. This procedure differs with each array; as such,
consult your storage array vendor documentation for more information on this.
Note
In order to resize an online file system, the file system must not reside on a partitioned device.
25.14 .1. Resiz ing Fibre Channel Logical Unit s
After modifying the online logical unit size, re-scan the logical unit to ensure that the system detects
the updated size. To do this for Fibre Channel logical units, use the following command:
$ echo 1 > /sys/block/sdX/device/rescan
Important
To re-scan fibre channel logical units on a system that uses multipathing, execute the
aforementioned command for each sd device (i.e. sd 1, sd 2, and so on) that represents a path
for the multipathed logical unit. To determine which devices are paths for a multipath logical
unit, use mul ti path -l l ; then, find the entry that matches the logical unit being resized. It is
advisable that you refer to the WWID of each entry to make it easier to find which one matches
the logical unit being resized.
25.14 .2. Resiz ing an iSCSI Logical Unit
After modifying the online logical unit size, re-scan the logical unit to ensure that the system detects
the updated size. To do this for iSCSI devices, use the following command:
# iscsiadm -m node --targetname target_name -R
[7]
Replace target_name with the name of the target where the device is located.
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