cannot connect to azure sql paas from azurevm behind a private loadbalancer RRS feed

  • Question

  • Hi 

    I have setup 2 VM behind a private load balancer (Standard sku).  VM are in a private network.  I am not able to connect to Azure SQL Server (PaaS), telnet to port 1433 does not work.

    If i remove VMs from the loadbalancer everything works fine.  This confirms that my windows firewall is not blocking my outbound traffic to sql server.  

    Seems when i add both vm behind laodbalancer, its blocking.  Where should i add rule to open port 1433 as i dont see any outbound option on loadbalancer



    Monday, February 10, 2020 9:14 AM

All replies

  • Hi, 

    When you have a VM behind Standard Internal Load balancer, outbound Internet is blocked. You need to create an Outbound rule with Standard Public LB to get outbound connectivity for your SQL VM. 

    Reference: https://docs.microsoft.com/en-us/azure/load-balancer/load-balancer-outbound-rules-overview



    Monday, February 10, 2020 10:40 AM
  • Hi

    I am not connecting to sql hosted on a VM.  I am connecting to Azure Sql (PaaS ) from Azure VM (which are behind internal load balancer)

    Internal loadbalnacer does not have outbound rule configuration.  The link which you provided is our public LB

    Monday, February 10, 2020 10:47 AM
  • Hi, 

    Yes, I am referring to the outbound connectivity from the VM to PAAS. When your VM is part of ILB (Standard) outbound traffic to Internet is blocked. So, you need to have a Public Load balancer and create an outbound rule. (Outbound rule cannot be created via Portal.Use PowerShell of CLI) . 

    Or other alternative is to attach a Public IP to the VM to access the PAAS resource. 

    Monday, February 10, 2020 11:36 AM