That's true, but how can we guarantee the user comes back to the same server? Imagine this scenario:
- there are 2 web servers, ws01 and ws02, behind a load balancer (e.g. www.xceed.com)
- user requests page from www.xceed.com. load balancer sends them to ws01
- ws01 creates chart in /XceedTemp (or customized) path
- user gets back html with <img> chart tag
- the request for the <img> chart gets load balanced to ws02
- file does not exist on ws02
This doesn't usually happen since I think http keep-alives send you to the same machine. But we've seen it happen before. That's why in IIS, we create a virtual dir for /XceedTemp to point to a remote machine that is shared by all the web servers.
I was hoping that maybe there's a way to override the <img> link. That way we can have the <img> link have the full path - e.g. ws01.xceed.com/XceedTemp/chart.png instead of just the virtual path - /XceedTemp/chart.png.
The streaming approach would work, but it requires another .aspx page that doesn't really work in our situation. We'd need to somehow serialize all the info from the original page so that this .aspx can generate the chart.
