Configuring Windows backend¶

GfxLauncher can be used to launch RDP sessions to preconfigured Windows virtual machines. Access to these virtual machines are handled through a special prolog/epilog script for SLURM. This script will maintain a small database of which allocated VMs are in use by RDP-sessions. The prolog-script will also create a special file in the users home folder for any allocated vm:s during the life time of the job. After job termination the script will also remove this file.

To make sure the configured virtual machines are not used by other users the prolog/epilog can also be configured to logoff all users after a completed job and also enable/disable user accounts on the configured VMs.

Installing prolog/epilog script in SLURM¶

The prolog/epilog script, prolog, is provided in the source distribution in the slurmvm. To integrate this script in slurm it must be copied/linked to the slurm configuration directory to /etc/slurm/prolog and /etc/slurm/epilog scripts. The easiest way is to just create symbolic links from the source installation directory for the required files.

cd /etc/slurm
ln -s /[install-dir]/gfxlauncher/slurmvm/prolog prolog
ln -s /[install-dir]/gfxlauncher/slurmvm/prolog epilog
ln -s /[install-dir]/gfxlauncher/slurmvm/lhpcvm.py lhpcvm.py

Configuration of SLURM virtual node¶

A special node must be configured that will handle the allocation of the virtual machines. A typical configuration in the slurm.conf looks like this:

#virtual node for windows integration
NodeName=wg01    Procs=1 RealMemory=800 Sockets=1 CoresPerSocket=1 ThreadsPerCore=1 Gres=win10m:4 Feature=win,virt State=UNKNOWN
PartitionName=win Nodes=wg01 OverSubscribe=YES Default=NO  MaxTime=168:00:00 DefaultTime=00:01 ExclusiveUser=no State=UP

As the virtual node does not represent real hardware it has to be configured with the OverSubscribe=YES directive. This also enable the virtual node to be a small virtual machine with just enough resources to run the slurmd-daemon.

In the configuration above the virtual node wg01 maintains 4 virtual machnies as a consumable SLURM resource, Gres=win10m:4. This must match the actual configuration of the prolog/epilog script described in the next section.

Configuring the VM backend¶

The configuration of the prolog/epilog script is done through the configuration file /etc/slurm/lhpcvm.conf. On a high level the file defines the virtual machines configured by the node. The number of configured machines should correspond to the configured consumable resources in SLURM.

A typical configuration file for 4 virtual machines are shown below. The different sections are described in separate sections.

[DEFAULT]
loglevel = ERROR
manage_server = yes

[win10-default]
logoff_users_script = /root/rviz/bin/lunarc-logoff-all-users.sh
disable_user_script = /root/rviz/bin/lunarc-disable-aduser.sh
enable_user_script = /root/rviz/bin/lunarc-enable-aduser.sh
update_script = /root/rviz/bin/install-win-updates.sh

[win10m-ip22]
name=win10m-ip22
hostname=10.18.50.22
kind=win10

[win10m-ip23]
name=win10m-ip23
hostname=10.18.50.23
kind=win10

[win10m-ip24]
name=win10m-ip24
hostname=10.18.50.24
kind=win10

[win10m-ip25]
name=win10m-ip25
hostname=10.18.50.25
kind=win10

The [DEFAULT] section¶

The default section controls logging and settings that apply to all sections. The availble key words are described in the table below:

Variable	Description
loglevel	Level of logging can be VERBOSE, INFO, WARNING, ERROR, CRITICAL
manage_server	This variable controls if the virtual machines should be managed by the prolog/epilog script. yes enables logoff/enable/disable

The [win10-default] section¶

This section controls the behavior of nodes configured with the platform property kind=win10. Currently supported platforms are currently only win10

The variables that can be set in this section defines the scripts that will be called by the prolog/epilog script at start and end of the job. The different options are described in the table below:

Variable	Description
logoff_users_script	Script that is called with the virutal machine hostname. Should logoff all users.
disable_user_script	Script that is called with the username of the user account that should be disabled.
enable_user_script	Script that is called with the username of the user account that should be enabled.
update_script	Script that is called with the virtual machine hostname. Should update the node.

The virtual server configuration sections¶

Other sections in the configuration are configurations for each virtual server. A virtual server is configured with a section named with the available hostname of the server. The configuration variables for each section is described in the following table:

Variable	Description
name	Descriptive name of the virtual server.
hostname	Specific explicit hostname of the server.
kind	Platform of the virtual server. Currently only win10 is available.