Problem Type A:
Foglight Experience Viewer (FxV) replay truncates ( "cuts-off" / chops off / leaves out / drops / misses / doesn't display / doesn't show) the bottom portion of long/too big web pages. Also, we are seeing random hex numbers (such as 1ff8) at the tops of some of our web pages. When we looked at the Hit HTML Source, we see those random hex numbers not just at the top like what was showing up in the html page. When we scroll down the source, we see the hex numbers in other places in the html.
And/or in the FxV replay, our images are missing; instead, random number/letter strings are where the images would go. Refer to the attached screenshot, chunkingproblem.jpg,that demonstrates the problem.
Problem Type B:
Our pages are not showing most of their content . We see the header and footers but not the main content. But they are not "cut-off" at their bottoms after a certain length like in Problem Type A, above. Also, we do not see any random number/letter strings. However, in the Content Replay Hit Details in the 'Other' tab, we do see a "TruncatedResponse" exception.
Cause for Problem Type A:
The hits are being truncated because FxV has a maximum limit on the response size (the default is 256000). For these hits in the Hit Details, if you look at the Response Headers you wll see Transfer-Encoding equal to chunked. That means that the server doesnt know how big the content will be so it transmits it in chunks. Each chunk is preceded with a hex length code. Since the response was truncated, FxV couldnt properly de-chunk the response and so these hex length codes show up in the html.
Cause for Problem Type B:
The content is not chunked, that's why you don't see the hex numbers. But, it exceeded the max size so it was still truncated. You can also tell that it is not chunked because it does not say "Transfer-Encoding" equal to "chunked" in the response header for any of the Hits that have that "TruncatedResponse" exception
NOTE: missing segments in the traffic stream due to a dirty feed getting fed into the FxM Sniffer, can also result in these same symptoms. If so, the fix is to troubleshoot your network and make sure that no packets are being dropped by your network architecture/infrastructure, at some point.
For both types of Causes (A and B), in the FxV web console UI go to the Maximum Response Size in the Collector Group config in the FxV web console UI under (Configure | Collectors | press the little pencil icon to edit the Default Collector Group, or whatever other Collector Group you have if not the default). Increase the Maximum Response Size. This field is to specify the largest response that should be captured. Responses that exceed this limit will be truncated (for text hits) or replaced (non-text hits). These hits are not "dropped." The maximum size allowed is 5 MB.