Some subpages of my website don't get fully transmitted. Instead the stream just seems to stop. There are a couple of PHP warnings and messages that I think might be irrelevant (such as undefined variables and indexes). Then there is the following error in the error_log file:
[deflate:error] [pid 30608] [client 178.203.20.157:65337] AH01386: Zlib error -2 deflating data ((null)), referer: https://knipsakademie.de/mannheim
I found out that -2 means Z_STREAM_ERROR. But unfortunately I don't really understand what I am dealing with. The server is running Plesk 12.5.30 and PHP 5.6.22 as FPM.
phpinfo() tells me that zlib is enabled and that I have Stream Filters as follows: zlib.inflate, zlib.deflate and a Stream Wrapper setting named compress.zlib://
// this is not from php.ini but from the output of phpinfo()
zlib.output_compression = off
zlib.output_compression_level = -1
zlib.output_handler = [no value]
The strange thing is that this subpage works fine:
https://knipsakademie.de/frankfurt/gutschein
But this one gets the errors and isn't transmitted fully:
https://knipsakademie.de/mannheim/gutschein
The content on these two pages does differ but not the structure of the website itself. The content is pulled from a database. Now I do know that I generally have some kind of character set problem in this website because my JSON_encodes() only work with a workaround and I am kind of neglecting this problem since I don't fully understand how to address it. So I guess my question is: could this deflate issue have anything to do with character sets?
How can I get more information on this issue? Are there other server logfiles that I should look at?
Thanks for your help!!!
