The default Linux Kernel version of Azure Linux VM is 3.1x for CentOS 7, and 4.1x for CentOS 8.

You can check Linux Kernel version by:

$ uname -r

There are many benefits to upgrade the Linux Kernel, including performance, functionality and security improvement.

For example, mount option “nconnect" is only available on Linux Kernel 5.3 and above. It can spread your server’s networking connections to multiple network interface cards (NICs) to increase total number of TCP connections, and therefore to improve overall IOPS and throughput performance. Which will especially helpful when running HPC and EDA applications.

Performance best practice- running EDA workloads on Azure NetApp Files (microsoft.com)

Below the steps to upgrade the Linux Kernel on CentOS 7:

# Update repository
sudo yum -y update

# Enable the ELRepo Repository
sudo rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-2.el7.elrepo.noarch.rpm

# Install the ELRepo repository。
sudo rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
sudo yum -y --enablerepo=elrepo-kernel install kernel-ml

# Reboot the machine
sudo reboot

Below the steps to upgrade the Linux Kernel on CentOS 8:

# Update repository
sudo yum -y update

# Enable the ELRepo Repository
sudo dnf -y install https://www.elrepo.org/elrepo-release-8.el8.elrepo.noarch.rpm

# Install the ELRepo repository。
sudo rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
sudo dnf -y --enablerepo=elrepo-kernel install kernel-ml kernel-ml-devel kernel-ml-headers --allowerasing --skip-broken --nobest

# Reboot the machine
sudo reboot

After the reboot, you can check version again:

$ uname -r
5.12.11-1.el8.elrepo.x86_64

This article will show you how to create RAID 0 (for best performance), or RAID 1 (for fault tolerance) Array on an Azure Windows VM. And will take HB120v3 as example to stripe its 2 local 960GiB NVMe disks.

1. Open a command prompt and type “diskpart".

2. At the “DISKPART" prompt, type “list disk" to list all available disks in this VM. In this example we see 2 960GiB disks on Disk 0 and Disk 1.

DISKPART> list disk

  Disk ###  Status         Size     Free     Dyn  Gpt
  --------  -------------  -------  -------  ---  ---
  Disk 0    Online          960 GB      0 B
  Disk 1    Online          960 GB      0 B
  Disk 2    Online            8 GB      0 B
  Disk 3    Online            8 GB      0 B
  Disk 4    Online            8 GB      0 B
  Disk 5    Online          419 GB      0 B

Now repeat below steps 2.1 and 2.2 for every disk you would like to stripe together. That is 0 and 1 in this example.

2.1 Select the disk.

DISKPART> select disk 0

2.2 Convert the selected disk to dynamic.

DISKPART> convert dynamic

3. Create volume array on disk 0 and 1.

DISKPART> create volume stripe disk=0,1

DiskPart successfully created the volume.

4. Check the volume # with Type = “Stripe". Let’s say “5″ as example.

DISKPART> list volume

5. Select the volume and format it.

DISKPART> list volume 5
DISKPART> format quick recommended label="nvme"

6. Assign an available driver letter. Let’s say “d" as example.

DISKPART> assign letter d

Your new volume is ready to use now!

For Linux VM: Create RAID Array on Azure Linux VM – Raymond’s Tech Thoughts

This article will guide you how to automate the process to deploy an HPC environment on Azure, using an open source project AzureHPC.

The environment will look like below:

1. A Virtual Network named “hpcvnet" and a subnet named “compute".
2. A Virtual Machine named “headnode":
   • PBS job scheduler
   • 2TB NFS file system
3. A Virtual Machine Scale Set named “compute", which contains 2 instances.

Prerequisites:

1. A Linux environment, Windows 10 中的 WSL 2.0 as example with Azure CLI installed。Or you can just use CloudShell of Azure Portal.
2. An Azure subscription with sufficient quota including:
   • 1xDS8_v3 (8 cores)
   • 2xHC44rs (88 cores)

Step-by-step:

1. Download AzureHPC repo.

# log in to your Azure subscription
$ az login 

# mkdir your working environment
$ mkdir airlift 
$ cd airlift 

# Clone the AzureHPC repo 
$ git clone https://github.com/Azure/azurehpc.git
$ cd azurehpc 

# Source the install script 
$ source install.sh

There are many HPC templates in the /examples folder. Just change directory to the template folder and edit the config.json file.

2. Edit config.json.

# We will use /examples/simple_hpc_pbs template here
$ cd examples/simple_hpc_pbs 

# edit config.json
# vi config.json 
$ code .

Input values of “location", “resource_group", and “vm_type". You can also change network or storage settings as your desire.

3. Deploy the HPC environment.

$ azhpc-build

It should be completed around 10~15 mins.

4. Connect to “headnode" to check the HPC environment you just deployed.

Please note that /share is mounted, and /apps, /data, and /home directories are exported and accessible from PBS nodes. You can “ssh <PBSNODENAME>" to verify.

$ azhpc-connect -u hpcuser headnode
Fri Jun 28 09:18:04 UTC 2019 : logging in to headnode (via headnode6cfe86.westus2.cloudapp.azure.com)
$ pbsnodes -avS
$ df -h

5. As PBS is well installed and configured on “headnode", you can submit jobs and check jobs status.

$ qstat -Q

6. Delete the environment.

$ azhpc-destroy

Or just delete the whole resource group from Azure portal.