Re: [Bug-wget] Problem using GNU Wget 1.11.4 Windows version

[Micah Cowan]

On 03/18/2012 03:24 PM, JD wrote:
> When using wget with the -c option, it does recover and resume the download
> after network failures. However, after it finishes the download (in my case
> downloading
> Fedora-16-i386-DVD.iso), I run the sha256sum on the downloaded ISO and it is
> completely different to the value stored in the file of CHECKSUMS on the
> same
> page URL - http://mirrors.kernel.org/fedora/releases/16/Fedora/i386/iso/
> 
> I downloaded this iso at least twice, with the same result - the sha256sum
> performed on the file does not match the one at the above URL, and nor
> does it match the result of sha256sum performed on the previous downloads
> of the iso file.
> 
> So, something is not right with wget!!

As others have said, using a newer version is probably a good idea.

However, it's probably also worth asking where you got your wget from,
since we don't really provide official binaries for Wget. Perhaps it has
a special case...

It's also conceivable that it could be the server's issue, and isn't
doing HTTP ranged requests correctly. Whether because of wget, or
because of the server, the constantly varying sha256 sums are a clue
that it's not happening correctly (assuming, of course, that all files
are completely downloaded).

With a partially-downloaded iso, I'd say, make a note of exactly how
many bytes are in the partial download, and take a look at what the tail
end looks like. Then, when you continue the download, take a look at
that same spot, and see what you find. If HTTP headers suddenly appear
there, or you see what appears to be the beginning of the file at the
continuation point in the file, those are big clues. Also save a copy of
the original partial download, so you can continue it again and see if
you get different results, or if they're reproducible for the same-sized
partial download being continued.

And add the --debug flag to wget to get as much information about what's
going on as possible. If you manage to find out what's happening, you
may need these logs to know whether to blame wget, or kernel.org.

Hope that helps,
-mjc