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Showing posts from August, 2012

I made a GIF!

Recognizing Linux block device increased size

 When extending a SAN LUN or adding new storage, Linux requires some convincing before recognizing disk changes occurred.  The following commands, executed as root, are helpful when managing storage: # rescan-scsi-bus.sh # echo 1 > /sys/block/sdb/device/rescan # partprobe # fdisk -l # pvscan Command "rescan-scsi-bus.sh" is included in Red Hat's sg3_utils package.  It is not part of the default install, however I highly suggest adding it during post-install. There are no options and no man pages.  Run it to rescan for SCSI LUN or Fiber Channel SAN HBA changes.  This is not required if the block device is already recognized. Command "echo 1 > /sys/block/sdb/device/rescan" is simple and straightforward.  Directly instruct the block device, in the example 'sdb', to rescan for new partitions.  Remember the hardware is path /sys/block/[...], not path /dev/[...] used when mounting filesystems.  There are no man pages or options of course. If you