Topic: Cannot browse internet

[ocascante]

Hi, I have a sme server 7.5 working for a year. Suddenly, without any changes in the server or in the internet service provider, terminals can not browse internet. From admin menu, server  internet test is ok.
From server, I can successfully ping to google or any other websites. From terminals I can successfully ping too. But,  using Internet explorer or firefox I can load pages, using linux computers or windows computers. I disabled dansguardian, check the ports, etc.
Has anyone had this problem before?

Thanks.

Oscar Fonseca
Computer Engineer
Linux User: 483828

[Jáder]

do you try to ping IP and names ?
let's try on server first, later on any other computer:

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ping 8.8.8.8and after

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ping www.google.comand post results of each command.

If you have a ping returning ok for numbers but not names, it's a DNS problem.


After that, if everything it's ok, go to the configuration page of your browser and disable ANY proxy settings.
I have seen wrong proxy config on IE cause this to whole OS!

Do you have squid running? To verify:

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service squid status

[ocascante]

Thanks Jader,
ping ip and names are ok. Squid proxy is running and no proxy settings are enable in IE. As I mentioned before I did the testing in Firefox also, using Linux and Windows computers.
Also I did test using different dns servers, changing the proxy to transparent, removing dansguardian without success.

[Jáder]

so you can do any tests and tests works, but when do you try to access HTTP protocol it fails ?

Try to use wget to download a file. It works ?
Now try to access a file using CURL on linux server. It works ?

What about to use FTP protocol... it works ?

BTW: do you verify if you have FREE SPACE left on server ?
Once I got ZERO bytes free and lost all internet access... hehehe

[ocascante]

you are right, i can do any test and tests works, but i cannot access any website in firefox or IE.

using wget in server works!
accessing website information with curl in server works!

ftp access from terminal works!!

finally, I have a terabyte hard disk with 45% free.

[Jáder]

you are right, i can do any test and tests works, but i cannot access any website in firefox or IE.

using wget in server works!
accessing website information with curl in server works!

ftp access from terminal works!!

finally, I have a terabyte hard disk with 45% free.

Ok... now let´s do other tests:
try to use wget and FTP from other linux computers (if you have any) and try to use FTP and WGET for window (http://gnuwin32.sourceforge.net/packages/wget.htm) to discover them work on your computers.

FTP you can test using command line utilities on Win! 
on console of windows try: ftp ftp.novell.com

Or even Internet Explorer, access this address:  ftp://ftp.novell.com



and just to be sure you have left inodes, try:

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[root@urubu ~]# df -i
Filesystem            Inodes   IUsed   IFree IUse% Mounted on
/dev/mapper/main-root
                     2359296  111888 2247408    5% /
/dev/md1               26104      82   26022    1% /boot
none                   31748       1   31747    1% /dev/shm


[ocascante]

ok, using wget in a linux terminal i have an error:

--2011-05-30 09:43:32--  (intento:   http://softlayer.dl.sourceforge.net/project/macbuntu/macbuntu-10.04/v2.2/Macbuntu-10.04.tar.gz
Conectando a softlayer.dl.sourceforge.net|74.86.229.28|:80... conectado.
Petición HTTP enviada, esperando respuesta... Error de lectura (Conexión reinicializada por la máquina remota) en las cabeceras.
Reintentando.

left inodes are ok.

PD/ almost all computers in the network have linux

[Jáder]

ok, using wget in a linux terminal i have an error:

--2011-05-30 09:43:32--  (intento:   http://softlayer.dl.sourceforge.net/project/macbuntu/macbuntu-10.04/v2.2/Macbuntu-10.04.tar.gz
Conectando a softlayer.dl.sourceforge.net|74.86.229.28|:80... conectado.
Petición HTTP enviada, esperando respuesta... Error de lectura (Conexión reinicializada por la máquina remota) en las cabeceras.
Reintentando.

left inodes are ok.

PD/ almost all computers in the network have linux

My guess is you have a bad proxy (maybe a transparent one) in your path... just this can explain.

Could you try this:

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[root@urubu ~]# traceroute 8.8.8.8
And watch about for something strange ? (if you don´t have a problem with this, post results here so all can help)

[ocascante]

jader,
Finally I found the solution and now is working ok again, but i am not sure if this can be catalogued as a bug.
I started installing a new server with the same configuration, and compare the opened ports, they were the same.
Since the problem seemed to be in the proxy,  I tried deactivating the condition of the http proxy to disabled in server-manager/security/proxy configuration. (I did this due to the fact that this the only proxy option you can change in sme server manager)
And....now i have http access.
Them, I erased all the files in /var/log/squid because this option (http proxy) is to use cache.
I returned to activate again this option and now I have http access.

Thanks again for your help and  I would like to read your opinion about this error.

[Jáder]

I think your proxy wasn´t disabled and "had problems" ...
You should had used

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service squid stop
to stop squid for good.

The reason could be squid log size... if you go beyond 2GB it could cause this kind of problem... but SME has tools to take care of that!
By any changes you saw size of log files (or have that in any cache/log) ?

[ocascante]

Jader,

i did service squid stop an start a few times....without success.
Access.log has 129Mb, cache.log 98Mb and store.log 71Mb. Hard disk 1 TB. Free space 593Gb.

[Jáder]

Jader,

i did service squid stop an start a few times....without success.
Access.log has 129Mb, cache.log 98Mb and store.log 71Mb. Hard disk 1 TB. Free space 593Gb.

ok... so watch out for all log sizes... they never should go beyond 2GB... just to be at safe side!