Enabling the localdisk option


You can skip this section if not using the localdisk option in your litefile table.

Define how to partition the local disk

When a node is deployed, the local hard disk needs to be partitioned and formatted before it can be used. This section explains how provide a configuration file that tells xCAT to partition a local disk and make it ready to use for the directories listed in the litefile table.

The configuration file needs to be specified in the partitionfile attribute of the osimage definition. The configuration file includes several sections:

  • Global parameters to control enabling or disabling the function
  • [disk] section to control the partitioning of the disk
  • [localspace] section to control which partition will be used to store the localdisk directories listed in the litefile table
  • [swapspace] section to control the enablement of the swap space for the node.

An example localdisk configuration file:







The two global parameters enable and enablepart can be used to control the enabling/disabling of the functions:

  • enable: The localdisk feature only works when enable is set to yes. If it is set to no, the localdisk configuration will not be run.
  • enablepart: The partition action (refer to the [disk] section) will be run only when enablepart=yes.

The [disk] section is used to configure how to partition a hard disk:

  • dev: The path of the device file.
  • clear: If set to yes it will clear all the existing partitions on this disk.
  • ptype: The partition table type of the disk. For example, msdos or gpt, and msdos is the default.
  • fstype: The file system type for the new created partitions. ext4 is the default.
  • parts: A comma separated list of space ranges, one for each partition that will be created on the device. The valid format for each space range is <startpoint>-<endpoint> or <percentage of the disk>. For example, you could set it to 100M-10G or 50. If set to 50, 50% of the disk space will be assigned to that partition.

The [localspace] section is used to specify which partition will be used as local storage for the node.

  • dev: The path of the partition.
  • fstype: The file system type on the partition.

the [swapspace] section is used to configure the swap space for the statelite node.

  • dev: The path of the partition file which will be used as the swap space.

To enable the local disk capability, create the configuration file (for example in /install/custom) and set the path in the partitionfile attribute for the osimage:

chdef -t osimage <osimage> partitionfile=/install/custom/cfglocaldisk

Now all nodes that use this osimage (i.e. have their provmethod attribute set to this osimage definition name), will have its local disk configured.

Configure the files in the litefile table

For the files/directories to store on the local disk, add an entry in the litefile table:



you do not need to specify the swap space in the litefile table. Just putting it in the partitionfile config file is enough.

Add an entry in policy table to permit the running of the getpartition command from the node

chtab priority=7.1 policy.commands=getpartition policy.rule=allow

Run genimage and packimage for the osimage


enablepart=yes in partition file will partition the local disk at every boot. If you want to preserve the contents on local disk at next boot, change to enablepart=no after the initial provision. A log file /.sllocal/log/localdisk.log on the target node can be used for debugging.