SID-00964: configure chicken-and-egg problem after disabling mod_perl

Status:	Answered	TWiki version:	5.0.0	Perl version:	5.8.8
Category:	CategoryInstallation	Server OS:	openSUSE 10.2 with Plesk 8.3	Last update:	15 years ago

I've been trying for days to get configure to work. I think it comes down to the mod_perl chicken-and-egg problem. I'm on Linux (openSuse) running Apache 2.2.3. I've tried disabling mod_perl by removing it from APACHE_MODULES in /etc/sysconfig/apache2 and removing mod_perl.conf from /etc/apache2/conf.d. Both ways, when I create /etc/apache2/conf.d/twiki.conf and then restart apache (apache2ctl -k restart), it doesn't restart correctly and no pages display. Looking in /var/log/apache2/error_log always has that "Content-type: text/plain\n\nPerl error when reading LocalSite.cfg" error. Can anyone suggest a proper form of action? I'm trying to disable mod_perl so I can configure twiki, and the instructions say it MUST be disabled before I can configure twiki. I guess I need to know how to disable mod_perl and how to confirm that it is disabled. Both methods above didn't seem to work out.

-- MatthewTaft - 2010-09-09

Discussion and Answer

The issue you describe is not a mod_perl issue. You actually do not need to remove/uninstall mod_perl from Apache, what the docs meant to convey is to not enable mod_perl for the TWiki scripts. That is, don't add directives SetHandler perl-script, PerlResponseHandler ModPerl::Registry to the <Directory "/var/www/twiki/bin"> section. In fact, unless you have thousands of users I do not recommend using mod_perl. Details in ApacheConfigGenerator (which I recommend to use).

As for "Content-type: text/plain\n\nPerl error when reading LocalSite.cfg" error, I have never seen it, so I only can guess. The twiki/lib/LocalSite.cfg file gets generated the first time you run the configure script in your browser. Make sure that the twiki/lib/ directory is writable by your Apache user (wwwrun on Suse?).

-- PeterThoeny - 2010-09-09

Hi Peter, thanks for the advice. I'm totally stumped here. I hope you won't mind if I provide more detailed information. I figure the more info I provide, the better chances of someone discovering where I've screwed this up.

I used the ApacheConfigGenerator and copied the resulting confi info into /etc/apache2/conf.d/twiki.conf. (Notice I commented out the whole <IfModule mod_perl.c> section in the <Directory ".../bin"> section so that mod_perl would not be enabled for the TWiki scripts. Did I do this right?

# Autogenerated httpd.conf file for TWiki. # Generated at http://twiki.org/cgi-bin/view/TWiki/ApacheConfigGenerator

# We set an environment variable called blockAccess. # # Setting a BrowserMatchNoCase to ^$ is important. It prevents TWiki from # including its own topics as URLs and also prevents other TWikis from # doing the same. This is important to prevent the most obvious # Denial of Service attacks. # # You can expand this by adding more BrowserMatchNoCase statements to # block evil browser agents trying the impossible task of mirroring a twiki # # Example: # BrowserMatchNoCase ^SiteSucker blockAccess # BrowserMatchNoCase ^$ blockAccess

BrowserMatchNoCase ^Accoona blockAccess BrowserMatchNoCase ^ActiveAgent blockAccess BrowserMatchNoCase ^Attache blockAccess BrowserMatchNoCase BecomeBot blockAccess BrowserMatchNoCase ^bot blockAccess BrowserMatchNoCase Charlotte/ blockAccess BrowserMatchNoCase ^ConveraCrawler blockAccess BrowserMatchNoCase ^CrownPeak-HttpAgent blockAccess BrowserMatchNoCase ^EmailCollector blockAccess BrowserMatchNoCase ^EmailSiphon blockAccess BrowserMatchNoCase ^e-SocietyRobot blockAccess BrowserMatchNoCase ^Exabot blockAccess BrowserMatchNoCase ^FAST blockAccess BrowserMatchNoCase ^FDM blockAccess BrowserMatchNoCase ^GetRight/6.0a blockAccess BrowserMatchNoCase ^GetWebPics blockAccess BrowserMatchNoCase ^Gigabot blockAccess BrowserMatchNoCase ^gonzo1 blockAccess BrowserMatchNoCase ^Google\sSpider blockAccess BrowserMatchNoCase ^ichiro blockAccess BrowserMatchNoCase ^ie_crawler blockAccess BrowserMatchNoCase ^iGetter blockAccess BrowserMatchNoCase ^IRLbot blockAccess BrowserMatchNoCase Jakarta blockAccess BrowserMatchNoCase ^Java blockAccess BrowserMatchNoCase ^KrakSpider blockAccess BrowserMatchNoCase ^larbin blockAccess BrowserMatchNoCase ^LeechGet blockAccess BrowserMatchNoCase ^LinkWalker blockAccess BrowserMatchNoCase ^Lsearch blockAccess BrowserMatchNoCase ^Microsoft blockAccess BrowserMatchNoCase ^MJ12bot blockAccess BrowserMatchNoCase MSIECrawler blockAccess BrowserMatchNoCase ^MSRBOT blockAccess BrowserMatchNoCase ^noxtrumbot blockAccess BrowserMatchNoCase ^NutchCVS blockAccess BrowserMatchNoCase ^RealDownload blockAccess BrowserMatchNoCase ^Rome blockAccess BrowserMatchNoCase ^Roverbot blockAccess BrowserMatchNoCase ^schibstedsokbot blockAccess BrowserMatchNoCase ^Seekbot blockAccess BrowserMatchNoCase ^SiteSnagger blockAccess BrowserMatchNoCase ^SiteSucker blockAccess BrowserMatchNoCase ^Snapbot blockAccess BrowserMatchNoCase ^sogou blockAccess BrowserMatchNoCase ^SpiderKU blockAccess BrowserMatchNoCase ^SpiderMan blockAccess BrowserMatchNoCase ^Squid blockAccess BrowserMatchNoCase ^Teleport blockAccess BrowserMatchNoCase ^User-Agent\: blockAccess BrowserMatchNoCase VoilaBot blockAccess BrowserMatchNoCase ^voyager blockAccess BrowserMatchNoCase ^W3C blockAccess BrowserMatchNoCase ^w3search blockAccess BrowserMatchNoCase ^Web\sDownloader blockAccess BrowserMatchNoCase ^WebCopier blockAccess BrowserMatchNoCase ^WebDevil blockAccess BrowserMatchNoCase ^WebSec blockAccess BrowserMatchNoCase ^WebVac blockAccess BrowserMatchNoCase ^Webwhacker blockAccess BrowserMatchNoCase ^Webzip blockAccess BrowserMatchNoCase ^Wells blockAccess BrowserMatchNoCase ^WhoWhere blockAccess BrowserMatchNoCase www\.netforex\.org blockAccess BrowserMatchNoCase ^WX_mail blockAccess BrowserMatchNoCase ^yacybot blockAccess BrowserMatchNoCase ^ZIBB blockAccess BrowserMatchNoCase ^$ blockAccess

<IfModule mod_perl.c> # Mod_perl preloading PerlRequire /srv/www/vhosts/[domainname]/subdomains/twiki/httpdocs/tools/mod_perl_startup.pl PerlSwitches -T </IfModule>

# The ScriptAlias defines the bin directory as a directory where CGI # scripts are allowed. # The first parameter will be part of the URL to your installation e.g. # http://example.com/twiki/bin/view/... # The second parameter must point to the physical path on your disc. ScriptAlias /twiki/bin "/srv/www/vhosts/[domainname]/subdomains/twiki/httpdocs/bin"

# The Alias defines a url that points to the twiki pub directory, which # is the root of file attachments. Alias /twiki/pub "/srv/www/vhosts/[domainname]/subdomains/twiki/httpdocs/pub"

# This specifies the options on the TWiki scripts directory. The ExecCGI # and SetHandler tell apache that it contains scripts. "Allow from all" # lets any IP address access this URL. <Directory "/srv/www/vhosts/[domainname]/subdomains/twiki/httpdocs/bin"> AllowOverride None Order Allow,Deny Allow from all Deny from env=blockAccess

Options ExecCGI FollowSymLinks SetHandler cgi-script

# Password file for TWiki users AuthUserFile /srv/www/vhosts/[domainname]/subdomains/twiki/httpdocs/data/.htpasswd AuthName 'Enter your WikiName: (First name and last name, no space, no dots, capitalized, e.g. JohnSmith)' AuthType Basic

# File to return on access control error (e.g. wrong password) ErrorDocument 401 /twiki/bin/view/TWiki/TWikiRegistration

# Limit access to configure to specific IP addresses and or users. # Make sure configure is not open to the general public. # It exposes system details that can help attackers. <FilesMatch "^(configure)$"> SetHandler cgi-script Order Deny,Allow Allow from all </FilesMatch>

# Enable mod_perl for the bin scripts listed # <IfModule mod_perl.c> # <FilesMatch \"(attach|edit|manage|rename|save|upload|view|rest|.*auth).*\"> # SetHandler perl-script # PerlResponseHandler ModPerl::Registry # PerlSendHeader On # PerlOptions +ParseHeaders # </FilesMatch> # </IfModule> </Directory>

# This sets the options on the pub directory, which contains attachments and # other files like CSS stylesheets and icons. AllowOverride None stops a # user installing a .htaccess file that overrides these options. # Note that files in pub are not protected by TWiki Access Controls, # so if you want to control access to files attached to topics you need to # block access to the specific directories same way as the ApacheConfigGenerator # blocks access to the pub directory of the Trash web <Directory "/srv/www/vhosts/[domainname]/subdomains/twiki/httpdocs/pub"> Options None AllowOverride None Order Allow,Deny Allow from all Deny from env=blockAccess

# Disable execusion of PHP scripts php_admin_flag engine off

# This line will redefine the mime type for the most common types of scripts AddType text/plain .shtml .php .php3 .phtml .phtm .pl .py .cgi # #add an Expires header that is sufficiently in the future that the browser does not even ask if its uptodate # reducing the load on the server significantly #IF you can, you should enable this - it will improve your twiki experience, even if you set it to under one day. # you may need to enable expires_module in your main apache config expires_module libexec/httpd/mod_expires.so mod_expires.c #<ifmodule mod_expires.c> # <filesmatch "\.(jpg|gif|png|css|js)$"> # ExpiresActive on # ExpiresDefault "access plus 11 days" # </filesmatch> #</ifmodule> #

</Directory>

When I write this file and restart apache, it doesn't restart successfully (no pages are accessible on the web server, not even our livewatch.php script on another domain).

As to LocalSite.cfg: This file has still not been created in twiki/lib. I've recursively set ownership to the twiki directory to wwwrun:www, and the current recursive permissions of lib are drwxrwxr-x.

The exact error in /var/log/apache2/error_log is:

[Thu Sep 09 21:04:10 2010] [error] Content-type: text/plain\n\nPerl error when reading LocalSite.cfg: \nPlease inform the site admin.\nBEGIN failed--compilation aborted at /srv/www/vhosts/[domainname]/subdomains/twiki/httpdocs/lib/TWiki.pm line 523.\nCompilation failed in require at /srv/www/vhosts/[domainname]/subdomains/twiki/httpdocs/bin/attach line 41.\nBEGIN failed--compilation aborted at /srv/www/vhosts/[domainname]/subdomains/twiki/httpdocs/bin/attach line 41.\nCompilation failed in require at (eval 7) line 1.\n

-- MatthewTaft - 2010-09-09

Hi again Peter,

I was able to solve my own problem here. I had to comment out another section of the config file. In this section:

<IfModule mod_perl.c> # Mod_perl preloading PerlRequire /srv/www/vhosts/mynayoki5.de/subdomains/twiki/httpdocs/tools/mod_perl_startup.pl PerlSwitches -T </IfModule>

I commented out the directive that requires the mod_perl_start.pl script, but kept the PerlSwitches -T directive. Now it looks like this:

<IfModule mod_perl.c> # Mod_perl preloading # PerlRequire /srv/www/vhosts/mynayoki5.de/subdomains/twiki/httpdocs/tools/mod_perl_startup.pl PerlSwitches -T </IfModule>

when restarting apache, now everything works! Thanks again.

-- MatthewTaft - 2010-09-09

I am glad it worked out.

We need to update the ApacheConfigGenerator with a checkbox to enable/disable mod_perl.

-- PeterThoeny - 2010-09-09

Hi Peter,

Good idea. I updated the ApacheConfigGenerator to include a checkbox for specifically "enabling" mod_perl. When not checked, the directives in the twiki.conf file are not written. There is still some more documentation below "mod_perl startup script" that someone could touch up... the information actually only applies when someone specifically checks the box to "enable" the start up script.

-- MatthewTaft - 2010-09-09

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