Hi, If I understood your first post correctly, there is 2 DHCP server (your two routers). What address are they offering ? Why you don't configure the DHCP on 3560 and turn off DHCP on your routeurs ? (at least to test if it's work). You can check "ip helper-address", to activate DHCP relay between different subnet or network. Regards, ... View more

I see, well thanks to both of you. I'll will check the alias thing, I didn't know that we can do this. Thanks again. Regards, Jonathan. ... View more

Thanks guys, A little update : Tools for stats : ntop => a great tool but not enough details for my use. Tools for traffic : iperf => easy to use For netflow, as I use cisco 2960, it's not possible, unless if a tool capable of doing the same thing exist. Do you know some ? lol (actually I found some tool on the net, fprobe who generate netflow frame and nfdump who collect and analyse the frame. But the results I have are not the results that I expected, if you have some infos on this tool) ... View more

Hi, I'm starting to understand the whole thing now. Just one last quick question, what is the best to use, dscp or cos label ? Or it doesn't matter because of the cos-to-dscp map ? And can we have trafic shaping and trafic sharing at the same time ? About the rating thing, It's all right if I rate all the answers ? They were very useful and I think it can answer to someone else question too. I will continue to read stuff about this topic, it's very interesting. A big thank you to both of you Shashank and Sweta. Regards, Jonathan. ... View more

I warn you, you are going to think that I'm a pain in the ass lol In a more general way, once I have done all my QoS configuration, how do I apply it ? It's just some exemple to help me understand the whole picture, I don't ask you to do the all configuration lol First case, I have one switch (just for the concept)         --------------         |  Switch  |         --------------           |       |     fa 0/1     fa 0/3           |       |    Client1   Client2 I wan't to give priority to the FTP trafic in both direction between Client1 and Client2 in case of congestion On fa0/1 : I apply my policy map with all the hierarchy that can be contain on it (class map, ACL) and also the configuration of the ingress queues to classify,mark and put into the queues the trafic On fa0/3 : I assume that I apply the same configuration that I put on fa0/1 right ? Since i wan't to prioritize the same trafic But what I should do for the egress part ? Put the same egress configuration on both interface ? Second case, I have two switch with a trunk between switch 1 gi0/1 ----------------- gi0/2 Switch 2       |                                             |   fa 0/1                                       fa 0/3      |                                              | Client1                                     Client2 Same scenario like the first one for the priority thing. On fa 0/1 and fa 0/3 : I see what I have to put for the ingress part, but not for the egress part on this interface ? On gi0/1 and gi0/2 : I see what I have to put for the egress part, but not for the ingress part ? I have a good picture on how the packet is processed and where is going to be sent but I don't see how the destination process the incoming packet, you see my problem ? lol That's a damn long post, but I'm so into the topic, it's hard not to ask questions about it, you know ... View more

Hi, Yes, this is very helpful, I'm starting to understand it a lot better with your explanation. I've got some other question for you. I warn you lol 1) About internal ring, It's like a very big buffer right ? Who hold the packets for forwarding them to the egress queues after ? How can I know the size of it ? 2) Am I forced to do Ingress policing ? If not in what scenario do we use it ? I've got some trouble to understand what are rate-bps and burst-byte values too 3) In general, what is the size of egress and ingress queue on a switch like a 2960 or 3750 ? That's it for the moment, I think... Thank you Shashank. Regards, Jonathan. ... View more

Hello, I have a question about threshold, I cant figure what is this and how it works, could you help ? An example if you want to base your explanation on it : Distribution1(config)#mls qos srr-queue input cos-map queue 2 threshold 3  3 5 Thank you so much. Regards, Jonathan. ... View more