cannot connect to ftp site from externel network

Hi PRADEEP PILLAI

Could you please check the below things:

• Ensure that there is an inbound rule allowing traffic on port 990. If you are using FTPS, you may also need to allow port 21 for the control connection.
• Check the Windows Firewall settings on the VM to ensure that port 990 is allowed.
• From an external machine, try pinging the public IP address of the Azure VM to ensure it is reachable.
• Ensure that the VM has a public IP address assigned and that you are using this IP to connect.
• Sometimes, restarting the FTP service or the VM itself can resolve connectivity issues.

Hope this helps!

Please Let me know if you have any queries.

Hello @PRADEEP PILLAI,

In addition to Reshma,

Is the VM traffic flowing through an Azure Firewall?

And could you check what is the priority of the port 21 inbound rule on the VM's NSG. Is it being blocked by another rule?

Did you open the required FTP ports in the OS Firewall on the FTP Server?

Are you able to connect to the FTP server from another Azure VM in the same subnet?

port 21 is working fine , but 990 is not working

Hello PRADEEP PILLAI

Could you please validate below details:

1.Check your FTP client is configured for FTPS (implicit) and not explicit FTPS or plain FTP.

Use the correct hostname/IP and port 990 and check if the client trusts the SSL certificate used by the server.

2.FTPS often uses passive mode, which requires a range of ports to be open.

Make sure the passive port range is defined in your FTP server settings and those ports are also allowed in:

• Azure NSG
• Windows Firewall
• Also Go to your VM's Network Security Group and ensure there's an inbound rule allowing TCP traffic on port 990.

Please check if an actual service is running on port 990 and if it is open in the VM OS level firewall.

Do let me know if you have further queries!

Hello PRADEEP PILLAI

I wanted to follow up and check if you had the opportunity to review the information provided in our previous post.

Kindly let us know if the above helps or you need further assistance on this issue.