Re: [squid-users] Hash Sum mismatches

On 10/12/10 11:21, Alex King wrote:
> I am running squid on a Debian machine, Version: 3.0.STABLE8-3+lenny3
>
> I have a situation where ubuntu updates are corrupted. The end users get
> a message about hash sum mismatches. If they re-try the update, squid
> delivers the same corrupted file.
>
> Yesterday they reported to me three specific files. I grabbed the three
> files (with wget) and confirmed they were corrupted. I then purged them
> from the cache and re-fetched them, and got the correct file.
>
> The corrupt and subsequent correct files are the same size. I inspected
> each of the three cases with vbindiff, and in each case the corruption
> is similar: the file sizes are identical, but there is one place where
> 32 consecutive bytes of data are corrupted. This happened neither at the
> beginning nor end, but at a different point in each case.
>
> This does not happen for every file downloaded, but often enough that
> many updates (of multiple files) or installs fail to work.
>
> I guess it could be a problem with the mirror site
> (http://nz.archive.ubuntu.com/ubuntu/), or it may be squid or something
> else on the local machine. An earlier version of squid
> (2.7.STABLE3-4.1lenny1) was also resulting in Hash Sum mismatch errors
> for the users. It's possible they may get corruption of other resources
> fetched via squid which I have not heard about.
>
> I am at a loss as to what to do next to locate the problem.

Upgrade to 3.1. Backports has a package which fixes the apt pipelining
and range problems.
  If it still occurs the areas to look are at what apt does when a
download is half complete and dies. Particularly what it requests out of
Squid to resume the file.

Amos

-- 
Please be using
   Current Stable Squid 2.7.STABLE9 or 3.1.9
   Beta testers wanted for 3.2.0.3