Hi Matthieu, sorry no one responded to your earlier post

I use QOS well to ensure key time sensitive services are not hampered by other traffic. This does mean you need to prioritise the traffic that is important to you (VOIP, DNS, SSH, small UDP packets etc)

Actually both apps work on the same premise, that anything you don't prioritise will be dropped into the 'bulk' traffic class with the lowest priority. This lowest class will use all remaining spare bandwidth up to the defined interface bandwidth limits (this answers #3). For the most reliable performance set these values to something just below what you realistically achieve (say 90% of your actual). You lose a little bandwidth but the benefit is a much more reliable connection.

Yes enumeration of IPs is not possible, I think the old bandwidth manager just created a rule for each IP rather than defining total bandwidth meant for a group

Thanks for summarising your other observations they will help someone else out

Replying to myself after some extensive trial and error.

1°) Which app is best suited to achieve those tasks ? QOS (beta) or Bandwith Management ?

It looks like QoS is a better and more complete answer in general when it comes to traffic management. Even if it is in beta, the QoS app looks stable and is doing the job.

There a few things to grasp before using it :

- The philosophy behind the configuration is the contrary of the one used for the Bandwidth manager app : everything that is not listed in the rules is getting lowest priority !

- Bandwidth manager and QoS apps don't play well together, disable or remove BM first.

- Therefore you'll need to specify everything you want be prioritised, like web traffic for example. At least it is my understanding right now.

- It is possible to specify range of ports by editing /etc/clearos/qos.conf directly using the iptable notation : xxxx:yyyy. However, specifying range of IP's isn't possible --> firewall-start -d stops and goes in "panic" mode, be prepared to access the console locally.

2°) I need the VOIP traffic to be able to flow from either the wan interfaces in order to achieve failover in case of problem. Is it going to be difficult ? What are the best practices in my case ?

As far as I can see this works without any configuration.

3°) Are either those apps able to allow the full bandwidth to an user if nobody else needs it, so that the system would throttle the bandwidth only if needed.

The bandwidth manager app does that. I still have to understand more deeply the QoS mechanism to determine if it is possible or not. It could be that the question doesn't make sense in that case.