As I mentioned in a article on Ubuntu Boot CD images, there’s a new boot CD image every day because the new version is being tested out. When the new version is finally released, work starts on version next, and daily builds start to come out again.
The problem is downloading a new 700MB file daily seems wasteful, and that’s 21GB of download per month, which your ISP may or may not like.
The solution is zsync, a binary file sychronization program.
Introduction to zsync
zsync uses the same algorithm as another file-syncing program, rsync. But zsync is better than rsync for file distribution where one file is going to multiple clients outside of a single organization. Also:
- zsync doesn’t require a program to run on the server. It runs on the client.
- zsync handles compressed files well.
You might wonder how zsync could possibly work with binary files, since a single small change can render the whole file totally different, and thus not practicably syncable. The answer is the zsync has special handling for gzipped files (files compressed with the gzip program).
First, if you haven’t already, add the universe repository to your list of software repositories. You can do this in System > Administration > Software Sources.
Then install zysync either by clicking here from Firefox or entering the following from the terminal:
sudo apt-get install zysnc
It only makes sense to use zysnc if you already have a full ISO image file that you want to update. So, first download an Ubuntu ISO image file.
Then, when there’s an update you want to get, go to the directory where the full image file is in a terminal. Then type zsync followed by the HTTP address of where the .zsync file is. (The .zsync file helps zsynch to correctly identify and apply updates.)
For the most often used Ubuntu CD image (the 32-bit desktop image), that would be:
You can find other .zsync files in the same place where the CD images are at Ubuntu downloads.
Note: At the end of this procedure, the updated file will have the same name as the old file. The old file is kept and saved with a “.zs-old” filename suffix.
zsync at work
zysnc first downloads the .zsync file.
Then it starts downloading the actual image file:
downloading from http://cdimage.ubuntu.com/daily-live/current/lucid-desktop-i386.iso: ###################- 96.3% 43.8 kBps
The image file is saved with a .part suffix during the download. If the download is interrupted, just run zsync again. It’ll pick up where it left off:
Read lucid-desktop-i386.iso.part. Target 92.4% complete. downloading from http://cdimage.ubuntu.com/daily-live/current/lucid-desktop-i386.iso: ##################-- 94.8% 43.8 kBps A
Once it’s done, it verifies the file:
verifying download...checksum matches OK used 663175168 local, fetched 55365870
Saving the .zsync file
The .zsync file is about 1.4MB. You can avoid downloading it again by using the -k option followed by the .zsync file.
If the local file has a different than that referenced in the .zsync file, specify the local filename with the -i option.
If you liked this article
If you liked this article, don’t forget to subscribe for updates!
Follow me on Twitter
Top Incoming Search Terms"www.thai-sbobet.com" +using zysnc +zsync ubuntu boot cd iso images cd image ubuntu file extension zsync how do use zsync? how does zsync work? how to download zsync files in windows how to open zsync how to use zsync how to use zsync files how to use zsynch ubuntu how to zsync http://cdimages.ubunto.com/daily-live/current http://digitivity.org/938/updating-ubuntu-boot-cd-iso-images-with-zsync-incremental-download iso.zsync files lucid bootcd lucid desktop zsync lucid lynx zsync lucid zsync mint linux +"zsync" download mint zsync rsync bootable image ubuntu rsync update ubuntu cd site:http://digitivity.org start update ubuntu from cd ubunt update dawnload iso ubuntu apply updates bootable image ubuntu boot image ubuntu bootable image as a single file; ubuntu bootcd ubuntu daily boot ubuntu daily cd images ubuntu daily zsync howto ubuntu update boot image ubuntu zsync ubuntu zsync windows ubuntu zsynch ubuntu.iso.part update lucid iso zsync update ubuntu daily zsync mb update ubuntu image latest updates update ubuntu using zsync update ubuntu with zsync update ubuntu zsync update ubunyu from iso image file update zsync update zsync from apt source updated ubuntu cd images updating ubuntu from from cd image updating ubuntu with cd upgrade cdimage zsync upgrade to lucid using iso cd use zsync to download ubuntu in windows using zsync using zsync lucid images what is zsync file extension what is zysync.com windows xp cd boot file 700mb zsync zsync file open zsync howto zsync iso zsync iso lucid zsync lucid zsync lucid iso zsync mint 15 zsync synchronise cdimage ubuntu zsync ubuntu zsync ubuntu daily zsync ubuntu iso zsync win32 zsync win32 binary zsync windows zsync windows update ubuntu iso zsync zs-old zsynch zysync server zysync.com
- How to Create an Ubuntu Boot CD for Lucid Lynx Ubuntu's getting ready to release the next version of it's...
- How to Install Google Chromium on Ubuntu Chromium is the open-source version of the Google Chrome web...
- Latest Windows XP Update Crashes Computers There are reports that Microsoft's latest update for Windows XP...
- Ubuntu Release Schedule Explained Mads Rosendahl created a great little video explaing the Ubuntu...
- Ubuntu Karmic Koala 9.10 Is Out The latest release of Ubuntu, the easy-to-use Linux distribution, is...