topic Re: squid+iptables: cant access stels.sec.samsung.com only - plz help in Operating System - Linux

squid+iptables: cant access stels.sec.samsung.com only - plz help

Maaz — Thu, 12 Apr 2007 07:06:27 GMT

Dear Experts
OS: SUSE Enterprise Server 10
#rpm -q iptables
iptables-1.3.5-13.2
#rpm -q squid
squid-2.5.STABLE12-18.2
Squid server is configured to run as a transparent proxy server. iptables, and squid are running on a single machine.

Dear all I have attached the
/etc/squid/squid.conf, /var/log/squid/access.log and iptables-script file, ... every thing is working fine users can browse almost all website and can chat using msn, and yahoo mesengers.

Prblm: ;(
when any client(either using win xp+IE, or either Linux+firefox) try to access the http://stels.sec.samsung.com/, browser doesnt show any thing, i.e web browser shows the blank page, while on status bar of web-browser(IE, or Firefox), it shows the status "Done".
But when I connect any of the client machine to the internet directly, i can access http://stels.sec.samsung.com/ ... no prblm

plz help, what should I do, so that my clients can access http://stels.sec.samsung.com/ if they are behind Proxy+Firewall server

Thanks in anticipation
Regards
Maaz

Re: squid+iptables: cant access stels.sec.samsung.com only - plz help

Ivan Ferreira — Thu, 12 Apr 2007 09:42:53 GMT

Try using the no_cache option.

Re: squid+iptables: cant access stels.sec.samsung.com only - plz help

Maaz — Fri, 13 Apr 2007 01:26:17 GMT

Thanks Ivan for help
i add the following in squid.conf

acl SAMSUNG1 urlpath_regex http://stels.sec.samsung.com/front/login/index.jsp
acl SAMSUNG2 urlpath_regex http://stels.sec.samsung.com

acl SAMSUNG3 url_regex http://stels.sec.samsung.com/front/login/index.jsp
acl SAMSUNG4 url_regex http://stels.sec.samsung.com

no_cache deny SAMSUNG1
no_cache deny SAMSUNG2
no_cache deny SAMSUNG3
no_cache deny SAMSUNG4

then
#squid -k reconfigure
but still fail to access http://stels.sec.samsung.com

Plz help
Regards
Maaz

Re: squid+iptables: cant access stels.sec.samsung.com only - plz help

Maaz — Fri, 13 Apr 2007 05:46:45 GMT

hope that the tcpdump output might assist you experts to diagnose/troublshoot the prblm I am facing.

here is the tcpdump output, on the gateway(Squid+Iptables) machine, when a client(10.0.0.121) was accessing http://stels.sec.samsung.com

#tcpdump -i $LAN_IN
15:25:04.148664 IP 10.0.0.121.59634 > 210.118.63.200.http: S 1408602740:1408602740(0) win 5840
15:25:04.148745 IP 210.118.63.200.http > 10.0.0.121.59634: S 981193054:981193054(0) ack 1408602741 win 5792
15:25:04.148857 IP 10.0.0.121.59634 > 210.118.63.200.http: . ack 1 win 1460
15:25:04.149908 IP 10.0.0.121.59634 > 210.118.63.200.http: P 1:423(422) ack 1 win 1460
15:25:04.149960 IP 210.118.63.200.http > 10.0.0.121.59634: . ack 423 win 1716
15:25:04.916057 IP 210.118.63.200.http > 10.0.0.121.59634: P 1:727(726) ack 423 win 1716
15:25:04.916309 IP 10.0.0.121.59634 > 210.118.63.200.http: . ack 727 win 1823
15:25:04.920789 IP 210.118.63.200.http > 10.0.0.121.59634: F 727:727(0) ack 423 win 1716
15:25:04.926239 IP 10.0.0.121.59634 > 210.118.63.200.http: F 423:423(0) ack 728 win 1823
15:25:04.926316 IP 210.118.63.200.http > 10.0.0.121.59634: . ack 424 win 1716

# tcpdump $INTERNET
15:25:04.151202 IP gateway.test.net.36322 > 210.118.63.200.http: S 974394621:974394621(0) win 5840
15:25:04.499294 IP 210.118.63.200.http > gateway.test.net.36322: S 273525633:273525633(0) ack 974394622 win 5792
15:25:04.499366 IP gateway.test.net.36322 > 210.118.63.200.http: . ack 1 win 1460
15:25:04.499577 IP gateway.test.net.36322 > 210.118.63.200.http: P 1:525(524) ack 1 win 1460
15:25:04.875427 IP 210.118.63.200.http > gateway.test.net.36322: . ack 525 win 6432
15:25:04.915368 IP 210.118.63.200.http > gateway.test.net.36322: P 1:610(609) ack 525 win 6432
15:25:04.915421 IP gateway.test.net.36322 > 210.118.63.200.http: . ack 610 win 1765
15:25:04.920441 IP 210.118.63.200.http > gateway.test.net.36322: F 610:610(0) ack 525 win 6432
15:25:04.920960 IP gateway.test.net.36322 > 210.118.63.200.http: F 525:525(0) ack 611 win 1765
15:25:05.262242 IP 210.118.63.200.http > gateway.test.net.36322: . ack 526 win 6432

Regards
Maaz

Re: squid+iptables: cant access stels.sec.samsung.com only - plz help

Steven E. Protter — Sat, 14 Apr 2007 23:27:54 GMT

Shalom,

There may be a DNS or networking problem at the site you mention causing this. Or it may be a fault in the squid proxy server and you may wish to file a bugzilla on this.

SEP

Re: squid+iptables: cant access stels.sec.samsung.com only - plz help

Huc_1 — Sun, 15 Apr 2007 01:36:48 GMT

Hello Maaz, from home "Brussels" I did a scan of stels.sec.samsung.com and I do see only

Interesting ports on 210.118.63.200:
Not shown: 1678 filtered ports
PORT STATE SERVICE
80/tcp open http
8080/tcp open http-proxy

Nmap finished: 1 IP address (1 host up) scanned in 77.235 seconds

I then try a coonection from linux -> firefox -> this show a loading text inside browser page if I click on this the mouse arrow becoms busy and stays that way, nerver end loading. .... BUT it does load if I allow javascripts to run from firefox..

Have you solved this ?...

or is only true to some of use only ?
keep us informed, of where problem did lie if you know this.

what ever, Enjoy life.

Jean-Pierre Huc

Re: squid+iptables: cant access stels.sec.samsung.com only - plz help

Maaz — Mon, 16 Apr 2007 03:17:07 GMT

Thanks Dear SEP, and HUC for reply

Dear SEP
>here may be a DNS or networking problem at the site you mention causing >this.
I dont think becuase, we can access http://stels.sec.samsung.com, when we bypass the squid.

>Or it may be a fault in the squid proxy server and you may wish to file a >bugzilla on this.
Yes.. I have submitted the bug at http://www.squid-cache.org/bugs/ and the Bug# is "1934"

Dear HUC
>BUT it does load if I allow javascripts to run from firefox.
I think Javascript is enabled by-default.
firefox > Edit > Preferences > Content
Enable Java
Enable JavaScript
both options are enabled(check)
As I have said that with default IE/Firefox settings, I can access http://stels.sec.samsung.com... only when machines are not behind the Squid(i.e connected to the internet directly)
But once machines are behind squid, I cant access http://stels.sec.samsung.com.

>Have you solved this ?...
NOPE ;(

>keep us informed, of where problem did lie if you know this.
I am not sure, but all the evidence shows, that this is a squid bug

Thanks n Regards

Re: squid+iptables: cant access stels.sec.samsung.com only - plz help

Maaz — Mon, 16 Apr 2007 07:08:48 GMT

downloaded the latest version of squid(2.6-STABLE), and this version of squid works quite fine i.e I can access http://stels.sec.samsung.com, using squid.
then obviously... the bug is in the squid binary version(Squid-2.5.STABLE12-18.2) shiped with SUSE Enterprise 10.

Thanks
Regards
Maaz

Re: squid+iptables: cant access stels.sec.samsung.com only - plz help

Maaz — Tue, 17 Apr 2007 23:49:33 GMT