[ale] [Semi-OT] Intermittent web connection loss but not network loss

[James P. Kinney III]

On Wed, 2004-07-07 at 10:52, Keith Morris - IQ wrote:
> I have been racking my brain on this and googling all over the place but 
> have yet to find a solution and was hoping someone here my have some 
> insight.
> 
> I have a network of about 40 machines that connect to the internet 
> through a Smoothwall firewall running iptables. About a month ago, 
> different clients on the network started losing web access. When this 
> happens, most of the time they can still check email, ftp, IM, ping, 
> access network shares, etc. just lose web access (though occasionally 
> they will loose one of the other services). Interestingly, it doesn't 
> happen to all clients at the same time, generally only 1 machine will 
> exhibit this at a time.
> 
> The clients are WinXP machines.  Sometimes a simple ipconfig /release ; 
> ipconfig /renew will bring the connectivity back, but a logoff/logon 
> will ALWAYS bring the web connection back.

This smells like XP network parameter stupids. I have seen multiple XP
(home and Pro) systems that inxplicatively drop parts of the network
setup. The most often dropped part as DNS serves. The system seems to
cache some stuff so it appears that the box is sort-of working (i.e. can
hit some places and not others). I've seen this with dhcp and static IP
systems. It also is not brand specific (on motherboard, CPU, or NIC). I
suspect that the registry is corrupted but no enough to cause a total
failure. 

Turn up the logging on the smoothie box and try to compare time stamping
to see if the incidents correspond with garbage packets hitting the
firewall.

> 
> DHCP and DNS is provided by a win2K ActiveDirectory server. It seems 
> that the Smoothwall should be completely unaware of the domain structure 
> and simply be routing based on MAC address and IP so it doesn't seem 
> that the Smoothie would just intermittently start dropping port 80 
> requests from a single client then recover after the user logged off and 
> back on (as the ip doesn't get touched in that situation).
> 
> I'm beating my head against a wall trying to figure it out. Any ideas?
-- 
James P. Kinney III          \Changing the mobile computing world/
CEO & Director of Engineering \          one Linux user         /
Local Net Solutions,LLC        \           at a time.          /
770-493-8244                    \.___________________________./
http://www.localnetsolutions.com

GPG ID: 829C6CA7 James P. Kinney III (M.S. Physics)
<jkinney at localnetsolutions.com>
Fingerprint = 3C9E 6366 54FC A3FE BA4D 0659 6190 ADC3 829C 6CA7
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: This is a digitally signed message part