Azure-based app times out when connecting with SA Services

[shawndewet]

I have a web-based application that has been running on local cloud provider for a number of years. It talks to two different SA-based services (accounting.sageone.co.za, and another 3rd-party FTP site also hosted in SA).
I have now deployed the web app to Azure (hosted in West Europe), and now I'm getting a number of timeouts in talking to these SA-based services.
Gut reaction is just to increase the timeout period, and this alleviates it to some extent. But there are still a LOT of timeouts happening, and sometimes even total failure to connect.
I don't see why talking to the SA-Based service from a server in West-Europe would be so much less performant than talking to the services from SA. I understand latency is a contributing factor, and that can be resolved with increased timeouts...but total inability to make a connection at all? That just seems odd.
Has anybody else got Azure-based services that talk to SA-based API's that have had this same problem?

 

[websquadza]

Can you post a traceroute between your Azure server and the local API server?
You may also need to look at reducing the interface MTU on your Azure server. We've seen MTU affect TLS/SSL handshakes, leading to timeouts. A few SA-based services are very sensitive to MTU issues and don't allow any fragmentation. Try an MTU of 1450.