In Azure, I have a virtual network (vNET) with following settings:

 Address space: 10.200.0.0/20
 subnet: 10.200.0.0/24

Inside the above vNET, I am trying to deploy an Azure Databricks with the following Network settings:

Public Subnet CIDR Range: 10.200.15.0/20
Private Subnet CIDR Range: 10.200.15.1/24

But on the Private Subnet CIDR Range above I get the following error:

Public and private subnet ranges must be valid and non-conflicting

Question: What I may be doing wrong, and how can I resolve the above error?

Remarks:

• I have tried various variations of 10.200.15.1/24(e.g. 10.200.15.0/24, 10.200.15.255/24 etc.) but I keep getting the same error. I am sure there must be a correct Private Subnet CIDR Range that I am not using.
• I noticed people have pointed out to some online tool such as the following, but I am not a networking expert, and I am not sure how exactly I can use these tools to get correct Private Subnet CIDR Range. CIRD Calculator, Subnet Calculator for IPV4, and IP Calculator.

CodePudding user response：

The CIDR tool I like to use is https://www.ipaddressguide.com/cidr.

Your public subnet 10.200.15.0/20 has a starting IP of 10.200.0.0 and ends with 10.200.15.255.

Your private subnet 10.200.15.1/24 is not even valid. You can check this SO answer as to why that is.

You can try using a public subnet of 10.200.15.0/24 and a private subnet of 10.200.16.0/24. These are not overlapping and completely valid.

CodePudding user response：

I tried to reproduce the same in my environment to create Azure Databricks Workspace with existing Vnet:

I have created Azure Databricks workspace with existing Virtual Network.

In your deployment you have mentioned public subnet CIDR range: 10.200.15.0/20 is in same Vnet Adress space range: 10.200.0.0/20, so there is a possibility of conflict the network.

To resolve the issue, create different subnet range for both Public and Private CIDR, while you are creating the Azure Databricks workspace.

I created a virtual network, like below.

1. Go to Azure Portal > Networking > Virtual Network.

2. Under IP address section, add the below IP configuration details.

5. Once Vnet deployment is complete, navigate to Virtual Network and select Address Space under settings option, add additional address space range, like below.

Created Azure Databricks workspace. like below.

1. Go to Azure Portal Analytics > Databricks.

2. Once Azure Databricks deployment is completed, check the Virtual Network assocaited with Databricks.

4. Once the cluster is deployment is completed, navigate to managed resource group in Azure Databricks and check the resources.

Check the Azure Databricks IP address range, like below.

Go to Azure Databricks workspace > Select your Cluster > Select Spark UI > Executors

Refer the Document more about Azure Databricks workspace