Create an Azure HPC Cache

Define basic details

In Project Details, select the subscription and resource group that will host the cache.

In Service Details, set the cache name and these other attributes:

• Location - Select one of the supported regions.

  If that region supports availability zones, select the zone that will host your cache resources. Azure HPC Cache is a zonal service.

• Virtual network - You can select an existing one or create a new virtual network.

• Subnet - Choose or create a subnet with at least 64 IP addresses (/24). This subnet must be used only for this Azure HPC Cache instance.

Choose cache type and capacity

On the Cache page, specify the type and size of cache to create. These values determine your cache's capabilities, including:

• How quickly the cache can service client requests
• How much data the cache can hold
• Whether or not the cache supports read/write caching mode
• How many storage targets it can have
• The cache's cost

Before you can choose throughput or storage capacity, you need to choose the cache type. Options include:

• Read-write standard caching: A flexible general-purpose cache
• Read-only caching: A high-throughput cache designed to minimize file access latency; modifications are handled with synchronous write-through operations
• Read-write premium caching (Preview): An NVMe-optimized cache with the lowest latency and highest throughput

Read more about these cache types below in Choose the cache type for your needs.

The "Standard" cache SKU lets you choose the cache's capacity for a given throughput selection, while the "Premium" and "read-only" caches have fixed capacities for each given throughput selection. The cache's capabilities are defined by two deployment choices:

• Maximum throughput - The data transfer rate for the cache, in GB/second
• Cache size - The amount of storage allocated for cached data, in TB

Understand throughput and cache size

Several factors can affect your HPC Cache's efficiency, but choosing an appropriate throughput value and cache storage size is one of the most important.

When you choose a throughput value, keep in mind that the actual data transfer rate depends on workload, network speeds, and the type of storage targets.

The values you choose set the maximum throughput for the entire cache system, but some of that is used for overhead tasks. For example, if a client requests a file that isn't already stored in the cache, or if the file is marked as stale, your cache uses some of its throughput to fetch it from back-end storage.

Azure HPC Cache manages which files are cached and pre-loaded to maximize cache hit rates. Cache contents are continuously assessed, and files are moved to long-term storage when they're less frequently accessed.

Choose a cache storage size that can comfortably hold the active set of working files, plus additional space for metadata and other overhead.

If you need help sizing your cache correctly, contact Microsoft Service and Support.

Choose the cache type for your needs

There are two basic cache types: "standard" and "premium".

Standard caches are general-use HPC Cache systems. You can select from multiple storage sizes after choosing your throughput value, and you can attach any of the HPC Cache supported storage target types.

Premium caches are designed for the highest-performance file service. They use high-throughput NVMe storage devices, which means that premium caches have a different pricing structure, static cache capacities, and cannot be temporarily stopped.

Cache options include:

• Read-write standard caching

  With standard caches, you can choose from several cache size values. These caches can be configured with storage target usage models for both read (write-through) and read-write caching.

• Read-only caching

  This type of cache provides higher throughput and lower latency than a standard cache, but is designed to optimize file and directory read access only. You cannot configure a read-only cache to use read-write cache usage models, but a read-after-write workload will result in a cache-hit, as the writes are persisted synchronously to the storage target. This type of cache has only one cache size option for each throughput choice.

• Read-write premium caching (Preview)

  A high-throughput cache that can be configured for either read-only or read-write caching. These caches have only one cache size option for each throughput option.

This table explains important differences among the three cache types.

All three caching options have a maximum storage target count of 20.

Learn more about these options:

• Read and write caching modes

Enable Azure Key Vault encryption (optional)

If you want to manage the encryption keys used for your cache storage, supply your Azure Key Vault information on the Disk encryption keys page. The key vault must be in the same region and in the same subscription as the cache.

You can skip this section if you do not need customer-managed keys. Azure encrypts data with Microsoft-managed keys by default. Read Azure storage encryption to learn more.

For a complete explanation of the customer-managed key encryption process, read Use customer-managed encryption keys for Azure HPC Cache.

Select Customer managed to choose customer-managed key encryption. The key vault specification fields appear. Select the Azure Key Vault to use, then select the key and version to use for this cache. The key must be a 2048-bit RSA key. You can create a new key vault, key, or key version from this page.

Check the Always use current key version box if you want to use automatic key rotation.

If you want to use a specific managed identity for this cache, configure it in the Managed identities section. Read What are managed identities for Azure resources? to learn more.

If you use a system-assigned managed identity or a user-assigned identity that doesn't already have access to your key vault, there is an extra step you must do after you create the cache. This manual step authorizes the cache's managed identity to use the key vault.

• Read Choose a managed identity option for the cache to understand the differences in the managed identity settings.
• Read Authorize Azure Key Vault encryption from the cache to learn about the manual step.

Add resource tags (optional)

The Tags page lets you add resource tags to your Azure HPC Cache instance.

Finish creating the cache

After configuring the new cache, click the Review + create tab. The portal validates your selections and lets you review your choices. If everything is correct, click Create.

Cache creation takes about 10 minutes. You can track the progress in the Azure portal's notifications panel.

When creation finishes, a notification appears with a link to the new Azure HPC Cache instance, and the cache appears in your subscription's Resources list.

Create the cache with Azure CLI

Set up Azure CLI for Azure HPC Cache.

Use the az hpc-cache create command to create a new Azure HPC Cache.

Supply these values:

• Cache resource group name

• Cache name

• Azure region

• Cache subnet, in this format:

  --subnet "/subscriptions/<subscription_id>/resourceGroups/<cache_resource_group>/providers/Microsoft.Network/virtualNetworks/<virtual_network_name>/subnets/<cache_subnet_name>"

  The cache subnet needs at least 64 IP addresses (/24), and it can't house any other resources.

• Cache capacity. Two values set the maximum throughput of your Azure HPC Cache:

  • The cache size (in GB)
  • The SKU of the virtual machines used in the cache infrastructure

  az hpc-cache skus list shows the available SKUs and the valid cache size options for each one. Cache size options range from 3 TB to 48 TB, but only some values are supported.

  This chart shows which cache size and SKU combinations are valid at the time this document is being prepared (July 2020).

  Cache size	Standard_2G	Standard_4G	Standard_8G
  3072 GB	yes	no	no
  6144 GB	yes	yes	no
  12288 GB	yes	yes	yes
  24576 GB	no	yes	yes
  49152 GB	no	no	yes

  Read the Set cache capacity section in the portal instructions tab for important information about pricing, throughput, and how to size your cache appropriately for your workflow.

Cache creation example:

az hpc-cache create --resource-group doc-demo-rg --name my-cache-0619 \
    --location "eastus" --cache-size-gb "3072" \
    --subnet "/subscriptions/<subscription-ID>/resourceGroups/doc-demo-rg/providers/Microsoft.Network/virtualNetworks/vnet-doc0619/subnets/default" \
    --sku-name "Standard_2G"

Cache creation takes several minutes. On success, the create command returns output like this:

{
  "cacheSizeGb": 3072,
  "health": {
    "state": "Healthy",
    "statusDescription": "The cache is in Running state"
  },
  "id": "/subscriptions/<subscription-ID>/resourceGroups/doc-demo-rg/providers/Microsoft.StorageCache/caches/my-cache-0619",
  "location": "eastus",
  "mountAddresses": [
    "10.3.0.17",
    "10.3.0.18",
    "10.3.0.19"
  ],
  "name": "my-cache-0619",
  "provisioningState": "Succeeded",
  "resourceGroup": "doc-demo-rg",
  "sku": {
    "name": "Standard_2G"
  },
  "subnet": "/subscriptions/<subscription-ID>/resourceGroups/doc-demo-rg/providers/Microsoft.Network/virtualNetworks/vnet-doc0619/subnets/default",
  "tags": null,
  "type": "Microsoft.StorageCache/caches",
  "upgradeStatus": {
    "currentFirmwareVersion": "5.3.42",
    "firmwareUpdateDeadline": "0001-01-01T00:00:00+00:00",
    "firmwareUpdateStatus": "unavailable",
    "lastFirmwareUpdate": "2020-04-01T15:19:54.068299+00:00",
    "pendingFirmwareVersion": null
  }
}

The message includes some useful information, including these items:

• Client mount addresses - Use these IP addresses when you are ready to connect clients to the cache. Read Mount the Azure HPC Cache to learn more.
• Upgrade status - When a software update is released, this message will change. You can upgrade cache software manually at a convenient time, or it will be applied automatically after several days.

Requirements

If you choose to use PowerShell locally, this article requires that you install the Az PowerShell module and connect to your Azure account using the Connect-AzAccount cmdlet. For more information about installing the Az PowerShell module, see Install Azure PowerShell. If you choose to use Cloud Shell, see Overview of Azure Cloud Shell for more information.

Install-Module -Name Az.HPCCache

Create the cache with Azure PowerShell

Use the New-AzHpcCache cmdlet to create a new Azure HPC Cache.

Provide these values:

• Cache resource group name

• Cache name

• Azure region

• Cache subnet, in this format:

  -SubnetUri "/subscriptions/<subscription_id>/resourceGroups/<cache_resource_group>/providers/Microsoft.Network/virtualNetworks/<virtual_network_name>/subnets/<cache_subnet_name>"

  The cache subnet needs at least 64 IP addresses (/24), and it can't house any other resources.

• Cache capacity. Two values set the maximum throughput of your Azure HPC Cache:

  • The cache size (in GB)
  • The SKU of the virtual machines used in the cache infrastructure

  Get-AzHpcCacheSku shows the available SKUs and the valid cache size options for each one. Cache size options range from 3 TB to 48 TB, but only some values are supported.

  This chart shows which cache size and SKU combinations are valid at the time this document is being prepared (July 2020).

  Cache size	Standard_2G	Standard_4G	Standard_8G
  3072 GB	yes	no	no
  6144 GB	yes	yes	no
  12,288 GB	yes	yes	yes
  24,576 GB	no	yes	yes
  49,152 GB	no	no	yes

  Read the Set cache capacity section in the portal instructions tab for important information about pricing, throughput, and how to size your cache appropriately for your workflow.

Cache creation example:

$cacheParams = @{
  ResourceGroupName = 'doc-demo-rg'
  CacheName = 'my-cache-0619'
  Location = 'eastus'
  cacheSize = '3072'
  SubnetUri = "/subscriptions/<subscription-ID>/resourceGroups/doc-demo-rg/providers/Microsoft.Network/virtualNetworks/vnet-doc0619/subnets/default"
  Sku = 'Standard_2G'
}
New-AzHpcCache @cacheParams

Cache creation takes several minutes. On success, the create command returns the following output:

cacheSizeGb       : 3072
health            : @{state=Healthy; statusDescription=The cache is in Running state}
id                : /subscriptions/<subscription-ID>/resourceGroups/doc-demo-rg/providers/Microsoft.StorageCache/caches/my-cache-0619
location          : eastus
mountAddresses    : {10.3.0.17, 10.3.0.18, 10.3.0.19}
name              : my-cache-0619
provisioningState : Succeeded
resourceGroup     : doc-demo-rg
sku               : @{name=Standard_2G}
subnet            : /subscriptions/<subscription-ID>/resourceGroups/doc-demo-rg/providers/Microsoft.Network/virtualNetworks/vnet-doc0619/subnets/default
tags              :
type              : Microsoft.StorageCache/caches
upgradeStatus     : @{currentFirmwareVersion=5.3.42; firmwareUpdateDeadline=1/1/0001 12:00:00 AM; firmwareUpdateStatus=unavailable; lastFirmwareUpdate=4/1/2020 10:19:54 AM; pendingFirmwareVersion=}

The message includes some useful information, including these items:

• Client mount addresses - Use these IP addresses when you are ready to connect clients to the cache. Read Mount the Azure HPC Cache to learn more.
• Upgrade status - When a software update is released, this message changes. You can upgrade cache software manually at a convenient time, or it is applied automatically after several days.