Can't change M30 tier cluster on cosmosdb to M20

Question

I decided I wanted to try the M30 tier cluster for my cosmosdb, however we have determined it is not necessary for our application. I wanted to downgrade back to the M20 tier, however the azure portal currently doesn't allow me. Is there a way to change this? The M20 is simply greyed out.

Answer 1

Hello @Jonathon Mayorga,

Thanks for using Q and A forum.

To downgrade your Azure Cosmos DB cluster from the M30 tier back to the M20 tier, you typically need to follow the scaling process outlined in the Azure portal. However, if the M20 tier is greyed out, it may indicate that the downgrade is not supported directly from your current tier. According to the Azure documentation, you can change the cluster tier at any time without interruption, but downgrading from certain tiers to a burstable tier (like M20) may not be supported. You can try the following steps:

1. In the Azure portal, navigate to your Cosmos DB cluster.
2. On the cluster sidebar, under Settings, select Scale.
3. If M20 is still greyed out, consider checking if there are any constraints or dependencies that prevent the downgrade. You may need to consult Azure support for specific guidance on your situation.

If you are unable to downgrade through the portal, you can use the Azure CLI to update:

Bash

az resource update \
   --resource-type "Microsoft.DocumentDB/mongoClusters" \
   --name "<cluster-name>" \
   --resource-group "<resource-group>" \
   --set properties.compute.tier="M20"

Make sure to replace <cluster-name> and <resource-group> with your actual cluster name and resource group.

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Answer 2

Hi @Jonathon Mayorga

It sounds like you're running into a bit of a roadblock trying to downgrade your Azure Cosmos DB cluster from the M30 tier to the M20 tier. Here's what you can do to resolve this:

Check for Region Availability: Sometimes, specific tiers may not be available in certain Azure regions. Ensure the M20 tier is supported in the region where your Cosmos DB instance is located.

Review Scale Settings: Sometimes, if there are existing scaling operations or changes in progress, you might not be able to change tiers. Make sure there are no ongoing operations before trying to downgrade again.

Manual Downgrade: If the portal is still grayed out, consider using PowerShell or Azure CLI to attempt the downgrade. Here's a quick guide:

• For Azure CLI, you can use the following command:

     az cosmosdb update --name <your-cosmosdb-account-name> --resource-group <your-resource-group-name> --default-consistency-level <desired-tier>
  

  - For **PowerShell**, the command would look something like this:

  
  powershell
  Set-Az CosmosDBAccount -ResourceGroupName <your-resource-group-name> -Name <your-cosmosdb-account-name> -DatabaseAccountOfferType M20

• Azure Cosmos DB Documentation
• Azure CLI Documentation
• Azure PowerShell Documentation
• https://learn.microsoft.com/en-us/azure/documentdb/limitations#m10m20m25-limits