Just a heads-up really, in case anyone else spends a long time banging their heads against a wall and swearing at Domino because of this.
Domino Server hosts a website where customers can download CD images of the company’s software. Image files are *.ISO files.
When the user tries to download the files, they get so far and then the transfer just hangs. If they re-try, the download will hang in roughly the same place each time. However, it stops at a different place on each file.
Logs report no problems. Other files (ZIPs, XLS, etc) seem to download OK. There are no size restrictions on the HTTP transfer settings.
It turned out that although the webserver is in a DMZ, the Checkpoint Firewall was ‘detecting’ mal-formed JPG’s in the the ISO file structure and dropping the link without telling either the browser or the server. Every ISO file failed, but all in different places. One would get to 12 meg and stop. Another got to 79 meg and stopped (all image files are over 150meg). And so on…
We lifted the strict detection rules and the files went through fine after that.
As I said, not really a Domino issue, but people do tend to point accusing fingers at Domino before looking elsewhere…!