Search squid archive

Re: Automatic switching of squid to a second internet link?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Danish Siddiqui wrote:

Hi,
Ive got squid proxy server running on a CentOS 4.4 machine. This proxy
server is connected to the internet through a Sonicwall PRO3060
firewall machine.

We have got three different ISP lines, one of which is used by squid.
All the three lines terminate at the firewall. One of these links then
goes to the squid server.
Many a times it happens that the internet link on the squid line goes
down, because of which we have to switch the squid server on to one of
the remaining ISP lines.

Hi Danish Siddiqui,

When the 1st ISP goes down, does that mean that you actually have to switch the cable from your squid box to the 2nd or 3rd ISP link on your Sonicwall machine?


I was planning a setup in which an extra NIC would be attached to the
squid server. This NIC would be connected to a different ISP line, so
that when one link goes down, the squid proxy server automatically
switches on to the next line, wherein the LAN users dont get to feel
the difference while browsing. Also, when the original link gets
restored, the squid server automatically switches back on to the
original link

If your Sonicwall firewall and routing policy allows you to access all 3 ISPs lines from your Squid box, I think that you can use the "tcp_outgoing_address" parameter to switch to either the 2nd or 3rd ISP connection when the 1st ISP goes down.

Of course, you must have a small script in Crontab to check for internet connectivity to your 1st ISP at regular intervals, say every 2 minutes.

If the 1st ISP gets internet connectivity again, then let the script restore connectivity from the 2nd or 3rd ISP back to the 1st ISP again.

But again, adding 2 extra NIC cards to your Squid box will provide you more control and fail over. In my opinion, it will be a very interesting option.

If your Squid box is running on Linux with a kernel greater than 2.4.20, then you can apply traffic and routing rules.

Please see the following link:

http://lartc.org/howto/lartc.rpdb.multiple-links.html

This guys really seem to perform some kind of magic with advanced routing and traffic control!



My current setup requires me to deny access to the squid server till
the time it is up again.

I suppose that you can't access all 3 ISPs lines from your Squid box?


Is this setup possible? And if yes, can you please tell me how or
point me to the necessary resources.

I definitely think it is possible. Let's wait and get more help and input from other experts and professionals from the Squid mailing list.


Thanking you...


Thanks
Danish The information contained in this electronic message and any attachments to this message are intended for the exclusive use of the addressee(s) and may contain proprietary, confidential or privileged information. If you are not the intended recipient, you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately and destroy the original message all copies of this message and any attachments. WARNING: Computer viruses can be transmitted via email. The recipient should check this email and any attachments for the presence of viruses. The company accepts no liability for any damage caused by any virus transmitted by this email.






--

With best regards and good wishes,

Yours sincerely,

Tek Bahadur Limbu

(TAG/TDG Group)
Jwl Systems Department

Worldlink Communications Pvt. Ltd.

Jawalakhel, Nepal

http://www.wlink.com.np

[Index of Archives]     [Linux Audio Users]     [Samba]     [Big List of Linux Books]     [Linux USB]     [Yosemite News]

  Powered by Linux