EBS -- Playing with Upload Limit top-down the stack - Upload File Size Limit, LimitRequestBody & SecRequestBodyLimit

In one of my Advanced Customer Support site visits, I came across an interesting issue related with the EBS file uploads.

Quickly check the Upload File Size Limit profile, as it is the only EBS side limit to the file size of an attachment. I have increased it up to a logical maximum ( A Quick lesson: Using lots of digits like 9999999 breaks the code it seems:), and retried. It just didn't help. The file upload screen recognized the new value, but the HTTP Server failed again while we were trying to upload the file. (file that I have used in my test was a PDF, and it was 350 MB in size)

It was clear that the issue was caused by some other limits configured in one (or two) technological components placed higher (or a little further on the front:) in the stack. So, I decided the check the Apache/Oracle Http Server configuration.

Two configuration parameter were visited. 

The first one was LimitRequestBody and actually it was managed with the Autoconfig (s_limitrequestbody) .. Checked the context file and saw that it was already set to unlimited (LimitRequestBody - from 0 (meaning unlimited) to 2147483647 (2GB)). It was a good try but no luck.. (as you may guess)

The second one was SecRequestBodyLimit (checked the see if it was set) set in the file named security2.conf placed in the following directory, $IAS_ORACLE_HOME/instances/EBS*/config/OHS/EBS*

security2.conf is the configuration file of the ModSecurity and it inspects the requests sent to the Web Server, which is Oracle HTTP Server in this case.

Added the following parameter in security2.conf;

SecRequestBodyLimit 1047527424

-- Note that, This parameter sets the maximum request body size ModSecurity will accept. This parameter is closely related with the file upload and it is set in bytes. (We have also SecRequestBodyNoFilesLimit parameter to play for tightening up the security , but it is another story -- not related with this case actually)

Anyways, after setting parameter, I restarted the Oracle HTTP Server, and tried to upload that big file again. This time it succeeded. The issue resolved!

Okay.. This was today's tip and it was for EBS community, because we don't find anything other than  Upload File Size Limit profile in the knowledge base. So I think this blog post may help to someone suffering from a same kind of issue.

Just a little extra info (something nice to have) -> Low heap sizes configured for Weblogic Managed Servers (especially for oacore) may also prevent us for doing these excessive stuff.. So increasing the heap size of Oacore Managed Server may be a good move -- not necessary but just in case)