Try reproducing Firefox Bug No. 611511

[Yedidyah Bar-David]

Hi all,

I am a sysadmin in ISOC-IL for some years, so far did not identify myself
as such...

On Wed, Dec 01, 2010 at 09:09:20AM +0200, Shlomi Fish wrote:
> Hi all,
> 
> Please try to reproduce this Firefox bug (that also happens in Opera and 
> Konqueror):
> 
> https://bugzilla.mozilla.org/show_bug.cgi?id=611511
> 
> [quote]
> When I access the URL (
> ftp://mirror.isoc.org.il/pub/mandriva/devel/cooker/i586/media/main/release/ ),
> firefox becomes unresponsive for many seconds, and the menus, buttons, tabs,
> etc. won't respond. This also happens with other pages and also HTTP pages.
> 
> I tried it in safe mode and was able to reproduce it there. I'm on Mandriva
> Linux Cooker on a Pentium 4 2.4 machine. I recall this started only a few days
> ago. I'm using the firefox-latest-nightly.
> 
> Reproducible: Always
> 
> Steps to Reproduce:
> 1. Type firefox -no-remote -safe-mode.
> 2. Go to the URL.
> Actual Results:  
> Firefox become unresponsive.
> 
> Expected Results:  
> Firefox should load the page while still allowing to interact with it.
> [/quote]
> 
> I'm on bezeqint.net.il.
> 
> Please comment on the bug report or here.

Well, a few notes:

1. It also happened now to me, using google-chrome 7.0.517.44-r64615.
It does not happen with lftp.

2. I looked at the server logs, and it seems to me to happen to all the
clients that use EPSV (Extended Passive mode, see rfc 2428 if interested).
At least most if not all of them seem to give up after up to around half
a minute and revert to "normal" Passive mode, which works.

3. It seems to be due to our filtering, which currently does not support
EPSV mode. I have no idea if iptables supports EPSV and how well - if
this is a serious issue, I can try looking at this. You are welcome to
"vote" by emailing our official address mirrormaster at isoc.org.il which
currently reaches Lior Kaplan and me.

4. The fact that a client, especially a sophisticated graphical one, gets
stuck for an extended time, is obviously a bug, so you are welcome to
continue with this venture of opening bugs and make them all behave more
nicely.

5. Since I do not know how, if at all, you can make firefox, and most
other clients, use normal Passive mode and not Extended, the simplest
workaround seems to me, for now, to be to use http. Any specific reason
for using ftp in this case?

6. I have no idea what caused it to start happening a few days ago. We
did not change anything on our side, as far as I know. Perhaps firefox
changed its behaviour on a version you recently updated to. I definitely
see in the logs such behaviour many months ago.

Regards,
-- 
Didi