Re: Apache Vulnerability in WebTen

On Mon, 24 Jun 2002, Ed Pastore wrote:

> >> I too cannot turn on Squid without encountering multiple serious problems,
> >> so need to know the extent of my vulnerability until I can move to a new
> >> server (a slow process, as it is still in budgeting, and as I have a lot of
> >> learning to do beforehand).
> >
> > What are these "multiple serious problems" that you are experiencing with
> > Squid on?
>
> I had numerous problems and every time I would report them to support,
> Stephanie's answer would be to turn off the cache.

Ed,

The advice you were given to turn off Squid in order to fix the problems
that you were having is absolutely incorrect.  I apologize for the
incorrect advice you were given.

>
> Looking through my old e-mails, I find that I finally decided to take
> Tenon's advice and turn off the cache after reporting this problem (and
> getting the same answer: turn off the cache):
> > When my WT memory allocation exceeds ~100 MB (due to Squid), WT decides
> > (both in Apache and FTP) that the modification date of every document should
> > be something recent (probably the moment when they were added to the cache).
> > The only way to fix it is to clear the cache AND reboot the server. This
> > results in a couple minutes of down-time that is starting to get me in
> > trouble with my company's management. It also means that when the dates show
> > incorrectly, our copyright information is incorrect, which could get us
> > into legal trouble.

Are you implying that the modification dates to files actually get changed
when the WebTen application's memory usage exceeds 100MB?  I doubt that
the memory usage would correlate to modification dates.  There may be
another issue at work here.

What is your Squid cache size set to?

I would like to look into this further and cross-reference it with our
list of known issues.  We may have a solution for you that doesn't include
degrading the performance of your server by turning off Squid.

>
> WebTen has indeed worked better since turning off the cache. It also gives
> me better control over the logging.

WebTen's speed is significantly slower when the cache is disabled.  I'm
surprised that you find that it is running better.

Hope this helps,

Erik.

-- 
Erik Lotspeich                          Lead Engineer
Tenon Intersystems                      erik@xxxxxxxxx
1123 Chapala Street Ste 200             805-963-6983
Santa Barbara, CA 93101-3142            http://www.tenon.com/