Protecting packages in yum

In my last post I gave a nice bit of advice on how to remove packages using sed, rpmorphan and yum but also warned that you could easily erase sshd or other programs that you might want.

In this short post I just want to mention that you can protect individual packages from being removed in yum. All you need to do is create a .conf file in /etc/yum/protected.d and add the names of the packages you wish to have protected. This is good for adding important things like your ssh server, or other programs that you might accidentally erase using the method I showed you, or by just using yum. It has happened to me before and I am glad this has been put into yum as a feature.

You can read more in the Fedora documentation.

Using rpmorphan on CentOS 6.4

So I just spent the night compiling and rebuilding RPMs on CentOS to get the exact set up that I would like and now I am left with several *-devel packages along with other development tools and libraries that I do not need any longer. Since this is a production environment, I would prefer to have as little extraneous packages as possible for various reasons.

Enter rpmorphan.

This nifty little tool will list all "orphaned" packages on your system. It would be VERY wise to add the packages that you wish to keep to the exclude list since common programs like wget don't have anything depending on them and will be listed in the output with each package to a line.

Adding a package to the exclude list is simple:

rpmorphan -add-keep wget

The above will add wget to your exclude list.

After you have all the packages you want to keep in your exclude list, removing all orphaned packages with yum is extremely simple:

yum remove `rpmorphan -all | sed ':a;N;$!ba;s/\n/ /g'`

This will run the output of rpmorphan through sed and replace all new lines with a space and use that as the argument list for yum remove. You should be very careful when doing this because I also noticed it listed openssh-server as an orphaned package. Be sure to add that in your exclude list. If not, I feel bad for you and hope you have console or physical access to your box because that would really suck.

Again, I will repeat: Use this at your own risk. If you remove something like your sshd you won't have access to your box. If you're sure that you can handle not doing something like that, this saves a lot of time and stress in the long run. Enjoy!

I would like to acknowledge Zsolt Botykai for his answer on stackoverflow in regards to the sed command. It was very helpful and explained very well.

Loading keys automatically with Pageant on Windows.

For those who work remotely on Linux from a Windows machine, they are probably familiar with the PuTTY set of tools for SSH connection management.

For managing keys in the PuTTY client you use pageant which, by default, when you open it will not load any keys. This is easily fixed just by creating a shortcut to the actual pageant program and in the box labelled 

"Target" you should see the path to the executable in double quotes. To load a key automatically when you click this shortcut, just type the full path to the key that you wish to load after the quotes. To add more than one key give a space separated list of full paths to each key you wish to load. 

Here are a couple of examples:

"C:\Program Files (x86)\PuTTY\pageant.exe" D:\SSH\mykey.ppk
The above will load the key "mykey.ppk" when you click on the shortcut.

"C:\Program Files (x86)\PuTTY\pageant.exe" D:\SSH\mykey1.ppk D:\SSH\mykey2.ppk D:\SSH\mykey3.ppk
The above will load the three keys when run from the shortcut.

As an added bonus, you could even place the shortcut in the startup start menu folder to have pageant start up on boot with all your keys loaded. Hopefully this saves someone some time. :)

SFTP Integration with Windows Explorer

I've come to notice that I very rarely use FTP for file transfers and have turned to using SFTP (FTP over SSH) instead for the two following reasons:
First, it is one less bit of software that I need to manage for my servers and second it is more secure. While I generally use Filezilla for most of my general purpose file transfer needs, I have also come across a nice little shell extension that integrates with Windows Explorer called Swish.

With Swish, you are able to log in to your servers through SSH either using password authentication, or through key authentication using pageant key manager. Upon logging in, you are able to navigate through your directories and files directly from Windows Explorer.

While it's a very useful and nice-to-have application, it is still in alpha. For the most part, I have not noticed any major errors that make it a shaky program to have. I think it's really worth a shot. Check it out at the Swish SFTP Homepage.

Apache Descriptions for Autoindexing

I've compiled a list of common just for my local instance of Apache and I thought I would share it since I haven't seen something like this before. It may be out there, but I haven't seen it. If you have any suggestions for additions or corrections post them in the comments and I will add them in and credit you.

These descriptions would go in the autoindex configuration file. It is commonly in a subdirectory where you find find httpd.conf. Usually in extras or conf.d or something to that effect. Enough talk, here is the list!

AddDescription "3GP Video" .3gp
AddDescription "3GP2 Video" .3g2
AddDescription "7-Zip Archive" .7z
AddDescription "Adobe Flash Application" .swf
AddDescription "Adobe Flex Project" .fxp
AddDescription "Adobe Portable Document Format" .pdf
AddDescription "Assembler Source File" .s
AddDescription "Audio Interchange File" .aif
AddDescription "Audio Video Interleave Video" .avi
AddDescription "Binary CPIO Archive" .bcpio
AddDescription "Binary Data" .bin
AddDescription "Bitmap Image File" .bmp
AddDescription "BitTorrent File" .torrent
#AddDescription "Blackberry COD File" .cod
AddDescription "Bourne Shell Script" .sh
AddDescription "Bzip Archive" .bz
AddDescription "Bzip2 Archive" .bz2
AddDescription "C Shell Script" .csh
AddDescription "C Source File" .c
AddDescription "Cascading Style Sheet" .css
AddDescription "CPIO Archive" .cpio
AddDescription "Debian Package" .deb
AddDescription "Document Type Definition" .dtd
AddDescription "Electronic Publication" .epub
AddDescription "E-Mail Message" .eml
AddDescription "Flash Video" .f4v .flv
#AddDescription "Fortran Source File" .f .f77 .f90
#AddDescription "GhostScript Font" .gsf
#AddDescription "GNU Tar File" .gtar
#AddDescription "GNU Texinfo Document" .texinfo
AddDescription "GIF Image" .gif
#AddDescription "H.261 Video" .h261
#AddDescription "H.263 Video" .h263
AddDescription "H.264 Video" .h264
AddDescription "HTML Document" .html .htm
#AddDescription "HyperText Application Language" .hal
AddDescription "Icon Image" .ico
AddDescription "Image Exchange Format" .ief
AddDescription "Java Archive" .jar
AddDescription "Java Class" .class
AddDescription "Java Source File" .java
AddDescription "Java Serialized Object" .ser
AddDescription "JavaScript File" .js
AddDescription "JSON File" .json
AddDescription "JPEG Image" .jpg .jpeg
#AddDescription "JPGVideo" .jpgv
#AddDescription "LaTeX File" .latex
AddDescription "M3U Playlist" .m3u
AddDescription "M4V Video" .m4v
#AddDescription "Microsoft Access Database"
AddDescription "MS Executable File" .exe
#AddDescription "MS Cabinet File" .cab
AddDescription "MS Excel File" .xls .xlsx
#AddDescription "MS HTML Help File" .chm
#AddDescription "MS Information Card" .crd
#AddDescription "Microsoft Money" .mny
#AddDescription "MS Powerpoint Presentation" .ppt
AddDescription "MS Windows Media Audio" .wma
AddDescription "MS Word Document" .doc .docx
#AddDescription "MPEG Audio" .mpga
AddDescription "MPEG Video" .mpeg .mpg
AddDescription "MP3 Audio" .mp3
AddDescription "MPEG-4 Audio File" .mp4a
AddDescription "MPEG-4 Video File" .mp4
#AddDescription "MPEG4 Application" .mp4
AddDescription "Ogg Audio" .oga
AddDescription "Ogg Video" .ogv
#AddDescription "MS Windows DLL File" .dll
AddDescription "Open Web Media Audio File" .weba
AddDescription "Open Web Media Video File" .webm
AddDescription "OpenType Font" .otf
AddDescription "TrueType Font" .ttf
AddDescription "Pascal Source File" .p
AddDescription "Adobe Photoshop Document" .psd
AddDescription "PNG Image" .png
AddDescription "PostScript File" .ai
#AddDescription "Adobe Illustrator File" .ai
AddDescription "PGP Signature" .pgp
AddDescription "Quicktime Video" .qt
AddDescription "RAR Archive" .rar
AddDescription "Rich Text File" .rtf .rtx
AddDescription "SVG Image" .svg
AddDescription "PHP Archive" .phar
AddDescription "TIFF Image" .tiff
AddDescription "Tar Archive" .tar
AddDescription "TeX File" .tex
AddDescription "Plain Text File" .txt
#AddDescription "URI List" .uri
AddDescription "vCard" .vcf
AddDescription "UUEncoded File" .uu
AddDescription "Windows Help File" .hlp
AddDescription "X.509 Certificate" .der .crt .x509
AddDescription "XML File" .xml .atom .rss
AddDescription "XSLT File" .xslt
AddDescription "YAML File" .yml
AddDescription "Python Script" .py
AddDescription "Perl Script" .pl .perl .cgi
AddDescription "PHP Script" .php .php1 .php2 .php3 .php4 .phtml
AddDescription "PHP Source File" .phps
AddDescription "PHP Test File" .phpt
AddDescription "SQL Dump File" .sql
AddDescription "Zip Archive" .z .Z .zip
AddDescription "C Header File" .h
AddDescription "C++ Source File" .cpp .c++ .cxx
AddDescription "Patch File" .patch
AddDescription "Diff File" .diff
AddDescription "Gzip Compressed File" .gz
AddDescription "XZ Compressed File" .xz
AddDescription "Server Parsed HTML File" .shtml
AddDescription "File Manifest" .manifest

Check if number is odd PHP

This is just a quick, simple function to check if a number is odd in PHP.

function odd($int) {
    if ($int % 2 === 0) {
        return false;
    } else {
        return true;
    }
}

My poor, forgotten blog.

I have abandoned you for almost a year. Perhaps I will post more VirtualBox and Linux goodies on you so I can forget about you for another year. I may or may not reply to comments. I apologize for the tardiness.