HomepageBlog

Prerequisites

Cache Configuration

Cache is required to fulfil these two main features:

  1. Data Archiving

  2. Scan LTFS Tape

Caching system has to be a block device which is seen behind /dev/ device or any supported mounted filesystem.

Here are some examples:

  • Internal RAID on local disks

  • Internal RAID on JBOD

  • SCSI Attached Storage

  • iSCSI Attached Storage

  • Linux based block replication (e.g., DRBD, GlusterFS, …).

How to proceed?

In case the disk used for the cache is not ready, you need to initialize it by executing the following commands.

First, run /opt/nodeum/bin/core/cache_disk_format.sh /dev/sdx (replace sdx by the correct device, likely sdb) to create the CACHE Disk.

The second step is to select the CACHE Disk with this command:

/opt/nodeum/bin/core/cache_disk_select.sh /dev/sdx (where sdx is the same device as the previous step).

Then the process will start.

Once done, the disk is configured as a cache and you can see its status:

Extend your cache

Based on the server type, you have multiple the solution to increase the cache size.

Backup your data

Before to extend the cache, copy all data of the cache into a secondary storage

Increase the disk volume capacity

RAID

Virtual Machine Datastore

Extend the volume partition

If the new disk partition will be greater than 16TB, the resize2fs command (version <1.43) will not work.

Error : "resize2fs: New size too large to be expressed in 32 bits"

To fix use a latest version Gparted ; this tool will provide this command in 64bits version. A procedure to use Gparted is decribed below.

Gparted procedure :

Use a Live ISO and edit the disk size graphically :

  1. Download the Gparted ISO (https://gparted.org/download.php)

  2. Creation of an USB key with Gparted ISO (in following Gparted Live CD/USB creation procedure : https://gparted.org/livecd.php).

  3. Boot on the Live ISO

    1. For Physical Server, this can be done with a CD/USB key or via Remote Management Server interface (where ISO image will be mapped as a CD).

    2. For Virtual Server, you have to boot the VM on the downloaded Gparted ISO.

  4. When the server boot, you will get the Gparted graphical interface.

  5. If you have a disk partition higher than 16 TB, you need to have a 64 bits file system. To convert your file system into 64 bits, you need to execute this command with th Gparted terminal : sudo resize2fs -b /dev/sdb1

  6. Select the Nodeum cache disk (most of cases, /dev/sdb1), the 'resize/move' option should be available, click on it.

  7. Drag the vertical bar to extend the partition size

  8. Once done, click on Resize/Move

  9. Once done, click on apply to save the changes to the disk

  10. Once the resize have finished, reboot the server and enjoy your new bigger Cache.

Command line interface procedure (available starting Nodeum 1.8 and higher)

sanity, if there are errors that are not fixed automatically, stop here (fix them before going to the next step)

If the operation fails, see Cautions 1 above.

Last updated

Was this helpful?