5. Frequently Asked Questions

5.1. Is it possible to limit bandwidth on a per-user basis with delay pools?

Yes. Look inside the original squid.conf file and check the Squid documentation on http://www.squid-cache.org

5.2. Is it possible to limit bandwidth on a per-user basis with cbq.init script?

Yes. Look inside this script; there are some examples.

5.3. CBQ sometimes doesn't work for no reason.

Generally it shouldn't occur. Sometimes, you can observe mass downloads, though you think you have blocked all ports Napster or Audiogalaxy uses. Well, there is always one more port open for mass downloads. To find it, you can use IPTraf. As there can be possibly thousands of such ports, it can be really hard task for you. To make it easier, you can consider running your own SOCKS proxy - Napster, Audiogalaxy and many programs can use SOCKS proxies, so it's much easier to deal with just one port (1080), than to do so with thousands of possibilites. Don't forget to close all ports for traffic, and leave open ports like 25 and 119 (SMTP and POP3), and other you think might be useful. You will find a link to NEC SOCKS proxy at the end of this HOWTO. If you intend to use it: don't forget to apply a patch that can be found on their page.

5.4. Delay pools are stupid; why can't I download something at full speed when the network is used only by me?

Unfortunately, you can't do much about it.

The only thing you can do is to use cron and reconfigure it, for example, at 1.00 am, so that Squid won't use delay pools, then reconfigure it again, let's say at 7.30 am, to use delay pools.

5.5. CBQ is stupid; why can't I download something at full speed when the network is used only be me?

Lucky you, it's possible!

There are to ways to achieve it.

The first is the easy one, similar to the solution we've made with Squid. Insert a line similar to the one below to your CBQ config files placed in /etc/sysconfig/cbq/:

TIME=15:00-16:00;110Kbit/11Kbit
TIME=00:00-08:00;110Kbit/11Kbit

You can have multiple TIME parameters in your CBQ config files.

The second way is harder, but more intelligent. You can read about it in the Linux 2.4 Advanced Routing HOWTO.