Linux: October 2007 Archives

Ubuntu is out today, but as of this writing the official Ubuntu site has not yet been updated with a download option for version 7.10, the "Gutsy Gibbon" release.

You can get it, however, if you're willing to search a little on the Ubuntu Mirrors. I'm currently downloading the desktop and the server editions of Ubuntu 7.10 from a German mirror while the official Ubuntu site still only makes version 7.04 available for download. Look in the ".pool" directories.

You don't need to download a new CD if you're simply upgrading your installation. Instead, if you want to get it while it's fresh from the oven and not yet on the store shelf, you may have to update your distribution source list to point to a mirror that hosts the most recent version of Ubuntu.

Assume you a set of files that you wish to post on the binary newsgroups; for example, a CD or a DVD with hundreds of Mbytes or maybe several Gbytes of data. There are a variety of applications that can do that for you, but sometimes it's convenient to use command line tools. (You'll need Linux for this.)

1. Install RAR. Just download the Linux distribution and unpack it. It contains an executable named "rar."
2. Install par2cmdline. I wasn't able to get the binary files to run on my system, and the source code wouldn't compile until I wrote this patch. Apply it to reedsolomon.cpp in the source code directory with "patch < par2cmdline.patch," and it will probably work.
3. Install cksfv.
   
4. Install newspost.

Some of these tools can be installed via apt-get.

You'll get three kinds of files to post: RAR archive files, PAR2 parity files, and an SFV checksum file. You should probably decide on a similar file name for each kind of file such as "mypost.rar", "mypost.par2", and "mypost.sfv".

The first thing you do is to compress the files and limit their size. You're about to spend a whole lot of bandwidth soon, so compress them tightly. In the following example, rarfilename is the name of the RAR output file (without the ".rar" extension), and the following files are the ones to be added to the archive. The example produces an archive that is split for every 50 Mbytes, includes recovery records, and applies maximum compression:

rar a -rr -m5 -v50000 rarfilename file1 file2 file3 ... filen

Next, expect errors on the news servers. Create so-called PAR2 recovery files containing at least 10% redundant information as follows. Again, omit the ".par2" extension from the PAR2 file name.

par2create -r10 -s262144 parfilename *.rar

As an optional step, you may want to create an SFV file with CRC-32 checksums for the posted files.

cksfv *.rar *.par2 > sfvfilename.sfv

You now have the compressed and split archive, recovery blocks for when the news servers around the world don't replicate the posts correctly, and a checksum file. Now it's time to post. yourusername and yourpassword may be required by your news server, but otherwise you may omit those switches. You can specify that the files are to be cross-posted to several newsgroups by separating the newsgroups with a comma; e.g., "-n alt.binaries.dvd,alt.binaries.dvdr". Everything else is hopefully self-explanatory:

newspost -i news.yournewsserver.com -u yourusername -p yourpassword \
  -f your@email.address -F "Your Name" -n alt.binaries.test \
  -s "Subject of the post" -q -y *rar *par2 *sfv

Now go get a cup of coffee. Or go to bed if your archive is several Gigabytes large, because your files are now posted to the news server.

The first time around, try the above with just a few small files, and use alt.binaries.test to verify that your files are posted. Oh, and limit the amount of cross-posting so you don't post your home videos to all of the erotica binary newsgroups.

If you know of similar tools that can be used to achieve the same effects, please let me know. I'm mostly interested in alternatives to par2cmdline and newspost.