RE: [squid-users] ssl-bump pause for 2 minutes for certain sites

2010-12-17 Thread Ming Fu
Hi Amos,

The pause happens when ICAP sends about 90% of the payload. The Content-Length 
header shown the exact size as 106900. I believe by the time squid starts to 
send the RESPMOD payload, all the DNS should already finished. 

If you look at the tcpdump on port 443, it pauses for 2 minutes and then RST by 
the web server. There is no additional data coming in after the pause from the 
webserver on port 443. So squid must already have the payload in full, but some 
how didn't do anything until kicked by the RST from the web server. After squid 
resume sending the ICAP payload, it actually sent in several 600 to 1400 sized 
packets. So it does not look like that the web server was holding back the 
payload.

Regards,
Ming


-Original Message-
From: Amos Jeffries [mailto:squ...@treenet.co.nz] 
Sent: December-16-10 8:49 PM
To: squid-users@squid-cache.org
Subject: Re: [squid-users] ssl-bump pause for 2 minutes for certain sites

On 17/12/10 08:45, Ming Fu wrote:
 Hi,

 When using squid 3.1.9 and ssl-bump, access to
 https://www.e-secure-it.com/info.html will cause squid RESPMOD to
 pause for about 2 minutes when sending the body playload to the ICAP
 server. The payload will eventually arrive. Just can't explain what
 happens during the 2 minute.

 Tcpdump on port 443 show that there is a pause during the end of SSL
 transaction with the e-secure. The time of the port 443 pause
 correlates to the pause of ICAP body upload. But there is no such
 pause when browser is direct connected to the e-secure site without
 squid in the middle.


You seem to have answered your own question. Sending stuff to that ICAP 
server is very slow.

Other things to consder:
  * Did the packets actually stop completely at that point? or did 
something else happen?
  * look at DNS etc as well. Squid may be waiting on the ICAP server 
name to resolve.
  * take a full packet traces (tcpdump -s 0 ...) and see what is 
actually being transfered to/from ICAP. It could be non-HTTP, broken 
syntax, or any kind of secondary encoding inside a HTTPS security channel.

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


Re: [squid-users] ssl-bump pause for 2 minutes for certain sites

2010-12-16 Thread Amos Jeffries

On 17/12/10 08:45, Ming Fu wrote:

Hi,

When using squid 3.1.9 and ssl-bump, access to
https://www.e-secure-it.com/info.html will cause squid RESPMOD to
pause for about 2 minutes when sending the body playload to the ICAP
server. The payload will eventually arrive. Just can't explain what
happens during the 2 minute.

Tcpdump on port 443 show that there is a pause during the end of SSL
transaction with the e-secure. The time of the port 443 pause
correlates to the pause of ICAP body upload. But there is no such
pause when browser is direct connected to the e-secure site without
squid in the middle.



You seem to have answered your own question. Sending stuff to that ICAP 
server is very slow.


Other things to consder:
 * Did the packets actually stop completely at that point? or did 
something else happen?
 * look at DNS etc as well. Squid may be waiting on the ICAP server 
name to resolve.
 * take a full packet traces (tcpdump -s 0 ...) and see what is 
actually being transfered to/from ICAP. It could be non-HTTP, broken 
syntax, or any kind of secondary encoding inside a HTTPS security channel.


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