mod_fcgid 3.2.6 MaxRequestLen new default value implies update to VirtualMin

Submitted by tristanleboss on Sat, 03/26/2011 - 10:06

Hello fellow VirtualMin-users,

I just made a fresh install of VirtualMin 1.534 (now updated to 1.535) on a Debian 6.0.1 x64 system. I use this oportunity to report all the issues I come by.

So, this new one seems to be linked to the new versions of "mod_fcgid" (at least since 2.3.6). Indeed, my customers started to complain about "Internal Server Error" after trying to upload files. I first checked the various options of "Resource Limits" page under "PHP 5 Configuration" with no luck. So I quickly moved to the Apache error_log file. Here, I found a lot of messages like this one:

[Fri Mar 25 19:51:04 2011] [warn] [client 2.3.141.189] mod_fcgid: HTTP request length 132104 (so far) exceeds MaxRequestLen (131072), referer: (nulled)

Then, after a small search on mod_fcgid website, I found this useful warning:

Warning: Before 2.3.6, this defaulted to 1GB. Most users of earlier versions should use this directive to set a more reasonable limit.

Source: http://httpd.apache.org/mod_fcgid/mod/mod_fcgid.html#fcgidmaxrequestlen

The new default value is "FcgidMaxRequestLen 131072" (131kb).

I think something need to be done in VirtualMin to enhance the user experience of new users because someone installing it on a new system will quickly faces this problem. I don't know if VirtualMin has to revert the value to 1gb, allowing to change "MaxRequestLen" value under "Resource Limits" page, put a warning on this same page, ...

Tristan

Status: 
Closed (fixed)

Comments

Submitted by tristanleboss on Sat, 03/26/2011 - 10:08

Just to update the title.

Submitted by JamieCameron on Sat, 03/26/2011 - 12:04

Thanks for pointing this out - the next Virtualmin release will set this directive for new or changed domains.

I'm actually rather annoyed that mod_fcgid made this change, as they are essentially breaking existing configurations. Adding a new directive would have been OK if the default was the same as the old default!

Also, there doesn't appear to be any reliable fully automated way of detecting if Apache supports FcgidMaxRequestLen or not, so for now Virtualmin will only set it if Debian 6 or later is being used.

Submitted by tristanleboss on Sat, 03/26/2011 - 12:59

Thanks for considering this issue.

This change is indeed annoying because, when I was googling the problem, I saw it's already silently breaking websites configuration arround the world.

By the way, I noticed there is another `Warning´ on the documentation page regarding another change introduced from mod_fcgid version 3.2.6:

Warning: Before 2.3.6, only one FastCGI application of any type (AAA or handler) can be used for a particular request URI. Otherwise, the wrong FastCGI application may be invoked for one or more phases of request processing.

It concerns directives 'FcgidAccessChecker', 'FcgidAuthenticator', 'FcgidAuthorizer' but, even if I don´t think so, you're the only one who really know if it can concerns VirtualMin.

Tristan

Submitted by JamieCameron on Sat, 03/26/2011 - 13:14

I don't think that latter issue will effect Virtualmin ..

Submitted by Issues on Sat, 04/09/2011 - 14:20

Automatically closed -- issue fixed for 2 weeks with no activity.