I have an azure VM from which I am trying to connect to a SFTP server. Sometimes the client connects just fine but after a few minutes of connectivity I then can't connect and just get a timeout error. This was initially from within code in an SSIS task, but I can replicate it in a normal FTP client (FileZilla).
I have contacted the SFTP server owner and given them the connection/failure log from Filezilla and they say that they are not seeing any activity or requests (and the server is functioning perfectly normally for other users). As a result they have suggested I:
"setup a network trace at your end and monitor the traffic. See if it’s actually leaving the external interface of your firewall..."
How do I do this? I have just the standard "SQL Server 2014 Enterprise on Windows Server 2012 R2" image, nothing special. I configured it with a reserved public IP address and gave this IP address to the SFTP owner so they could open their firewall to allow connections. But I simply don't know how to setup/monitor network traffic leaving the external firewall?
The pattern appears to be, I can connect to the SFTP server, then after some activity (which varies, maybe a few minutes of copying files), I can no longer connect, and then after some time period (30m - 2 hours, not sure exactly) I can connect again, for a while...and then I can no longer connect, and so on...the pattern repeats. A server reboot does not resolve the problem.
Pulling my hair out with this, it is really frustrating. Can you advise how I can setup the network trace? Or any other advice or suggestions as to the cause?
Thanks