« Previous | Next » 

Revision 376631d1

Parent 32ba31be
Child 938adc87

Added by Constantinos Venetsanopoulos over 11 years ago

Implement the External Storage Interface

With this commit we introduce the External Storage Interface
to Ganeti, abbreviated: ExtStorage Interface.

The ExtStorage Interface provides Ganeti with the ability to interact
with externally connected shared storage pools, visible by all
VM-capable nodes. This means that Ganeti is able to handle VM disks
that reside inside a NAS/SAN or any distributed block storage provider.

The ExtStorage Interface provides a clear API, heavily inspired by the
gnt-os-interface API, that can be used by storage vendors or sysadmins
to write simple ExtStorage Providers (correlated to gnt-os-interface's
OS Definitions). Those Providers will glue externally attached shared
storage with Ganeti, without the need of preprovisioned block devices
on Ganeti VM-capable nodes as confined be the current `blockdev' disk

To do so, we implement a new disk template called `ext' (of type
DTS_EXT_MIRROR) that passes control to externally provided scripts
(the ExtStorage Provider) for the template's basic functions:

create / attach / detach / remove / grow

The scripts reside under ES_SEARCH_PATH (correlated to OS_SEARCH_PATH)
and only one ExtStorage Provider is supported called `ext'.

The disk's logical id is the tuple ('ext', UUID.ext.diskX), where UUID
is generated as in disk template `plain' and X is the disk's index.

Signed-off-by: Constantinos Venetsanopoulos <>
Signed-off-by: Iustin Pop <>
[: small simplification in bdev code, pylint fixes]
Reviewed-by: Iustin Pop <>


  • added
  • modified
  • copied
  • renamed
  • deleted

View differences