Request Entity Too Large

The only thing that would work for me was to tune up the SSL Buffer Size. You can set this by...

<Directory /my/blah/blah>
...
  # Set this to something big...
  SSLRenegBufferSize 10486000
...
</Directory>

...and then just restart Apache for the change to take effect. (Found this at: http://forum.joomla.org/viewtopic.php?p=2085574)

You can also use "Location /" to simply apply the setting to a whole VirtualHost:

<VirtualHost *:443>
# ...
    <Location />
        SSLRenegBufferSize 101048600
    </Location>
# ...
</VirtualHost>

After you are over the raising of PHP's memory_limit, post_max_size and upload_max_filesize, I would like to recommend you some articles related to the topic, maybe one of them solves the problem.

I found this post on Server Fault:
https://serverfault.com/questions/79741/php-apache-post-limit/79745#79745

• sybreon suggests to double-check the Content-Length, and - citing - "ensure that you are directly connecting to Apache and not through either a proxy or a reverse-proxy. Some reverse-proxies place a cap on the maximum size of a request as a sort of security measure. So, you may want to check that as well as your Apache logs to ensure that nothing else is going on."

• sybreon also posted this link: Apache 413 error problems.
  The following is only applicable if you have mod_ssl module turned on in Apache. (Otherwise this setting can cause a server crash.)
  Citing the article:
  "I was using Apache SSL client certificates, which have a limit of 128K, and if re-negotiation has to happen, a larger POST will fail.
  This Bugzilla posting had the clues - You have to set the following as DEFAULTS for your SSL server, not just the directory.

  SSLVerifyClient require
  

  Otherwise it forces a renegotiation of some sort, and fails with a 413 error."

• The previous article also mentioned the LimitRequestBody directive.
  A guy says here that the appropriate setting of this directive solved his problem..

I hope one of these settings solves this problem!

My server is Apache. It was mod_security module which was preventing post of large data approximately 171 KB. I did below configurations in mod_security.conf

SecRequestBodyNoFilesLimit 10486000
SecRequestBodyInMemoryLimit 10486000