Metalink is an Open Standard that bundles the various ways (FTP/HTTP/P2P) to get files into one format for easier downloads. This makes it good for downloading ISOs; particularly for people who can't use P2P because of restrictions from their ISP or University. It can deliver very fast download speeds since most clients support multiple connections, to multiple mirrors, automatically.
Besides regular p2p/bittorrent, you can continue using Metalink to spread out the downloads between mirrors, either removing the listing for the main server or lowering its priority rating. Metalinks can list mirrors and checksums (repair info), along with torrents, ed2k, and magnet links. People can then download from local servers if they set their location, since the mirrors have location and priority information.
There is a definitive list of openSUSE metalinks at http://download.packages.ro/metalink/opensuse/
There are also "collection" metalinks which will add all the CDs for an architecture to your download queue at http://download.packages.ro/metalink/opensuse/collections/ (Basically like a .torrent that will download the same thing).
aria2 (Use aria2 and you won't have checksum errors, packages for openSUSE here) is the recommended Unix command line client, while KGet 2.0 in KDE 4 and wxDownload Fast (All platforms, but no Mac OS binary) (package for openSUSE here) have a GUI.
Speed Download is available for Mac OS, Retriever (Java) on all platforms, Free Download Manager (GPL), Orbit Downloader, GetRight, and Net Transport on Windows.
If you're comfortable trying beta software, DownThemAll!, a Firefox extension, supports Metalink.
There are other clients available for Mac OS, Windows, and Unix.
Example Usage of aria2
To download the 10.3 i386 DVD iso:
Or, if you've got the metalink file downloaded, you need the -M option. So:
People who use ReiserFS for their filesystem will want to use the '--file-allocation=prealloc' to avoid file fragmentation. It may take a minute or two to allocate space before the download begins for DVD ISOs, but it will save time later.
Metalinks can contain full file checksum information which will automatically be verified with aria2, Free Download Manager, GetRight, wxDownload Fast, Orbit, and Speed Download. Some Metalinks can also contain repair information to fix errors that may occur during download, but only aria2 0.10.1 and higher currently support this. (Use aria2 0.10.1+ and you won't have MD5 errors).
To be sure that the Metalink transfer did not contain any errors and matches official ISOs, you should compare this number for your own ISO image to checksums listed on an official mirror. A free md5sum checker for several operating systems can be found at md5deep.sourceforge.net. On Linux, run the command:
If there is any difference between the output of the md5sum command and the above number, the download is broken and should be repeated (or repaired).
If you are using Linux as OS, you may also repair the ISO file with the command rsync. To do that, choose a mirror that supports this protocol and enter the following:
This will show the content of the directory on the server. By appending the names of the subdirectories to the command, you can get to the directory where the ISO is located on the remote computer. Then
rsync -avvP rsync://<name-of-mirror>/<opensuse-directory>/<path-to-iso>/<name-of-ISO> <path-to-your-local-ISO-file>
will repair the file, only downloading the needed data to correct it. For further information please refer to the manpage of rsync, by entering (in a shell):
A lot of the mirrors on Factory_Mirror_List can be used with rsync. In this example we'll use the steady mirrors.kernel.org
This presupposes that you were downloading openSUSE-10.2-GM-DVD-i386.iso via metalink, and at some point (probably the end) you got an error. Use rsync like this to download any missing chunks:
cd /directory/ofthe/iso rsync -avvP rsync://mirrors.kernel.org/opensuse/distribution/10.2/iso/dvd/openSUSE-10.2-GM-DVD-i386.iso .
Note: we can just use a dot (".") at the end here since we simply want to continue the ISO with the same filename, in the current directory.