Azure application has code that talks to Storage services/AppFabric services/SQL Azure is encountering exception similar to below
"A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond 10.10.10.10:443"
"A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 0 - A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.)"
Note: Ip address, port number could be any combination depending on "service", the application is trying to connect to
Note: If the computer is unable to reach target services outside Azure, then, communicaton issue must be resolved before going any further. This blog entry http://blogs.msdn.com/b/narahari/archive/2011/08/01/ip-range-for-windows-azure-platform-identifying-connectivity-issues.aspx has a section to identify, troubleshoot such issues.
Issue happens if the machine that is running the program is behind corporate proxy (or firewall?) that allows traffic coming only from authenticated users. By default Azure/IIS configures AppPool to run under “NetworkService”. Hence, Proxy does not allow traffic coming from this account
Resolution / Workarounds
There are few ways this issue could be worked around.
fwctool enable /g /app:w3wp (This command allows w3wp traffic to go through firewall client program and ensures settings are applied globally, for all users)
Firewall Client Tool for ISA Server 2004http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=12168
Note: If you are using different firewall client other than Microsoft ISA client, you need to figure our similar command that can enable the traffic to go via firewall client configured on your machine. If you are unable to find the command, below are few options you can use to resolve the issue.
Note: Few of these techniques can be used to resolve the issue for Non-Azure web applications as well if you cannot change the AppPool identity to Domain Account(which is easier in On-premise scenarios)
Azure applications running in compute emulator environment