Free checking software for linux

check_writable is a Nagios plugin that checks if one or more directories are writable by checking that the supplied directory is indeed a directory, checking if the the filesystem permissions are OK, creating a temporary file, writing random data to the temporary file, and reading it back.

It returns a critical status if one of the tests fails.

Check Website is a performance monitoring and uptime notification tool. Check Website will check if a Website is up, and check the response time of the site.
The administrator can then choose to receive an email notification if the site is down, or if the site response time is too slow. All results are also written to a daily log file.
Enhancements:
- This release fixes some small bugs that caused hang ups in the program when checking Web sites.

With LinkChecker, you can check HTML documents for broken links. LinkChecker features recursion, robots.txt exclusion protocol support, HTTP proxy support, multithreading, regular expression filtering rules for links, i18n support and user/password checking for authorized pages.
Output can be colored or normal text, HTML, SQL, CSV, or a sitemap graph in DOT, GML, or XML format. Supported link types are HTTP/1.1 and 1.0, HTTPS, FTP, mailto:, news:, nntp:, Gopher, Telnet, and local files.
Main features:
- recursive checking
- multithreading
- output in colored or normal text, HTML, SQL, CSV or a sitemap graph in GML or XML.
- HTTP/1.1, HTTPS, FTP, mailto:, news:, nntp:, Gopher, Telnet and local file links support
- restriction of link checking with regular expression filters for URLs
- proxy support
- username/password authorization for HTTP and FTP
- robots.txt exclusion protocol support
- i18n support
- a command line interface
- a (Fast)CGI web interface (requires HTTP server)
Enhancements:
- Log output with certain Unicode characters is fixed now.
- XML output has been improved.
- Gopher URLs are now deprecated.

Search-Engine-Optimized project is a free online resource for anyone who wants to step up their search engine optimization strategies to the next gear.
The web is a constantly changing place, expecially search engines, but there are numerous search engine optimization strategies that are consistant across all the major search engines, and are probably going to be very useful for a long time to come.
Read on to learn what they are and how to employ them in the development of your web site.
Main features:
SEO Rank Checker is a nice little script for checking your keyword status for a few select keywords without going through the trouble of checking the search engine result pages yourself.
- Automated fetching of the top 100 results for MSN, Yahoo and Google to check for your site.
- Easy to read, compare and print output
- Installation is super easy, just upload to your server and youre done!
- Super small script, just a few KBs of space!

Recon is an SSL audit tool, checking for common, certificate-related errors in SSL-enabled services. Provide it a list of SSL services for which you are responsible, it runs them periodically, a Recon will warn you of impending certificate expirations, mismatched certificate names or unavailable services.

VacCon (short for Vacation Configurater) is a Web Interface for setting up and using the email auto-reply program vacation.
VacCon project is developed specifically for OpenBSD (due to the password checking requirements) but could quite easily be changed to work with other operating systems.
Enhancements:
- The documentation was updated to include full instructions required to use VacCon.

Ad Censor filters annoying ads by matching requested urls with a blacklist and checking the HTML code for suspicious tags.
Main features:
- Checks HTML data from HTTP connection for user defined patterns (e.g. ads) and deletes them.
- Works with any Browser (even without) because it is a proxy.
- Works even over a HTTP proxy.
- Has an easy to use GUI config editor.
- Filters can be defined with perl regex.
- Can also block cookies.