Linstor Storage Driver
This driver allows for highly available storage using DRBD9 + Linstor in OpenNebula.
To contribute bug patches or new features, you can use the github Pull Request feature. It is assumed that code and documentation are contributed under the Apache License 2.0.
Before sumbitting pull requests, please run the
./format.sh script found
in the root of the project and test using
Support for this addon can be found at the DRBD-User mailing list.
Hayley Swimelar firstname.lastname@example.org
- This addon is compatible with OpenNebula versions up to 5.6
- It was tested with version 5.6
- This version of README.md describes the installation process for ONE 5.6 environments
- This is intended for use as an images datastore for use with either an NFS shared
- system datastore or a SSH system datastore
- DRBD9 9.0.14+
- quickly attaches images to VMs
- fast image clones
- transfers images over the network in diskless mode
- allows for live migration even if the ssh system datastore is used
- snapshots of images are not available
Follow these steps on the Front-End node only.
Clone the Repository and Run the Install Script.
Run the following commands as either oneadmin or whichever user is filling the
ONE_USER role (or have the
ONE_USER environment defined):
python setup.py install
To upgrade the driver, simply run the above installation script again.
Configure the Driver in OpenNebula
Modify the following sections of
Add linstor to the list of drivers in the
TM_MAD = [ executable = "one_tm", arguments = "-t 15 -d dummy,lvm,shared,fs_lvm,qcow2,ssh,vmfs,ceph,linstor" ]
DATASTORE_MAD = [ EXECUTABLE = "one_datastore", ARGUMENTS = "-t 15 -d dummy,fs,lvm,ceph,dev,iscsi_libvirt,vcenter,linstor -s shared,ssh,ceph,fs_lvm,qcow2"
Add new TM_MAD_CONF and DS_MAD_CONF sections:
TM_MAD_CONF = [ name = "linstor", ln_target = "NONE", clone_target = "SELF", shared = "yes", ALLOW_ORPHANS="yes" ]
DS_MAD_CONF = [ NAME = "linstor", REQUIRED_ATTRS = "BRIDGE_LIST", PERSISTENT_ONLY = "NO", MARKETPLACE_ACTIONS = "export" ]
After making these changes, restart the opennebula service.
Configuring the Nodes
Overview of node Roles
The Front-End node issues commands to the Storage and Host nodes via Linstor
Storage nodes hold disk images of VMs locally.
Host nodes are responsible for running instantiated VMs and typically have the storage for the images they need attached across the network via Linstor diskless mode.
All nodes must have DRBD9 and Linstor installed. This process is detailed in the User's Guide for DRBD9
It is possible to have Front-End and Host nodes act as storage nodes in addition to their primary role as long as they the meet all the requirements for both roles.
The Front-End node must have the
linstor command in its
PATH. Please verify
that the control node(s) that you hope to communicate with are reachable from
the Front-End node.
linstor node list for locally running Linstor controllers
linstor --controllers "<IP:PORT>" node list for remotely running Linstor
Controllers is a handy way to test this.
Host nodes must have Linstor satellite processes running on them and be members
of the same Linstor cluster as the Front-End and Storage nodes, and may optionally
have storage locally. If the
oneadmin user is able to passwordlessly ssh between
hosts then live migration may be used with the even with the ssh system datastore.
Storage Node Configuration
Only the Front-End and Host nodes require OpenNebula to be installed, but the oneadmin user must be able to passwordlessly access storage nodes. Refer to the OpenNebula install guide for your distribution on how to manually configure the oneadmin user account.
The Storage nodes must use storage pools created with a driver that's capabile if making snapshots such as the thin LVM plugin.
In this example preparation of thinly-provisioned storage using LVM for Linstor, you must create a volume group and thinLV using LVM on each storage node.
Example of this process using two physical volumes (/dev/sdX and /dev/sdY) and generic names for the volume group and thinpool. Make sure to set the thinLV's metadata volume to a reasonable size, once it becomes full it can be difficult to resize:
pvcreate /dev/sdX /dev/sdY vgcreate drbdpool /dev/sdX /dev/sdY lvcreate -l 95%VG --poolmetadatasize 8g -T /dev/drbdpool/drbdthinpool
Then you'll create storage pool(s) on Linstor using this as the backing storage.
Permissions for Oneadmin
The oneadmin user must have passwordless sudo access to the
mkfs command on
the Storage nodes
oneadmin ALL=(root) NOPASSWD: /sbin/mkfs
Be sure to consider the groups that oneadmin should be added to in order to
gain access to the devices and programs needed to access storage and
instantiate VMs. For this addon, the oneadmin user must belong to the
group on all nodes in order to access the DRBD devices where images are held.
usermod -a -G disk oneadmin
Creating a New Linstor Datastore
Create a datastore configuration file named ds.conf and use the
tool to create a new datastore based on that configuration. There are two
mutually exclusive deployment options: LINSTOR_AUTO_PLACE and
LINSTOR_DEPLOYMENT_NODES. If both are configured, LINSTOR_AUTO_PLACE is ignored.
For both of these options, BRIDGE_LIST must be a space
separated list of all storage nodes in the Linstor cluster.
Deploying via auto placement
The LINSTOR_AUTO_PLACE option takes a level of redundancy which is a number between one and the total number of storage nodes. Resources are assigned to storage nodes automatically based on the level of redundancy. The following example shows a cluster with three storage nodes that will deploy new resources to two of the nodes that have the LINSTOR_STORAGE_POOL named "thin" configured on them.
cat >ds.conf <<EOI NAME = linstor_auto_place DS_MAD = linstor TM_MAD = linstor LINSTOR_AUTO_PLACE = 2 LINSTOR_STORAGE_POOL = "thin" BRIDGE_LIST = "alice bob charlie" EOI onedatastore create ds.conf
Deploying to a List of Nodes
Using LINSTOR_DEPLOYMENT_NODES allows you to select a group of nodes that resources will always be assigned to. In the following example, new resources will always be assigned to the nodes alice and charlie. Please note that the bridge list still contains all of the storage nodes in the Linstor cluster.
cat >ds.conf <<EOI NAME = linstor_nodes DS_MAD = linstor TM_MAD = linstor LINSTOR_DEPLOYMENT_NODES = "alice charlie" BRIDGE_LIST = "alice bob charlie" EOI onedatastore create ds.conf
Additional attributes that you may add to a datastore's template:
linstor_controllers can be used to pass a comma separated list of controller ips and ports to the Linstor client in the case where a Linstor controller process is not running locally on the Front-End:
cat >ds.conf <<EOI NAME = linstor_nodes DS_MAD = linstor TM_MAD = linstor LINSTOR_DEPLOYMENT_NODES = "alice charlie" LINSTOR_CONTROLLERS = "192.168.1.10:8080,192.168.1.11:6000" BRIDGE_LIST = "alice bob charlie" EOI onedatastore create ds.conf
This driver will use Linstor to create new images and transfer them to hosts. Images are attached to hosts across the network using diskless mode. Images are replicated according to the deployment policy set in the datastore template.
##DRBD9 and Linstor User's Guide
If you have any questions about setting up, tuning, or administrating DRBD9 or Linstor, be sure to check out the information provided in the User's Guide