Hello, Currently I use following htb configuration: --------------- 1:0 ----------- / | \ 1:1 1:2 1:x / | \ / | \ / | \ 1:1001 1:2001 1:3001 1:1002 1:2002 1:3002 Classes like 1:1,1:2,1:3 limit my clients to some value, let's say 128kbit/s. Classes like 1:1001 are used to divide and limit subflows of packets. I use complicated classification mechanizm based on time, packet size, protocol type, connection state, quota, source or destination port numbers etc. It is working very well. Anyway I have encountered some scalability issues, I have to solve before my shaping box collapses. # iptables -vnL FORWARD -t mangle | wc -l 2798 I have almost 3000 items in FORWARD chain in mangle table. Now I am switching to IPMARK target which can mangle packets automaticaly based on their src or dst address. IP address is converted to hex (ex. 10.11.12.13->0a0b0c0d), then 16 less importants bits are left (by and operation with $ffff0000- so it is 0c0d) and then I can OR with some number. I use class 192.168.0.0/16 for clients and I can't change that. So I want to create tree like this: --------------- 1:0 ----------- / | \ 1:0c0d 1:xxxx 1:xxxx | | 2:0 3:0 4:0 5:0 6:0 7:0 / | \ / | \ / | \ 2:0c0d 3:0c0d 4:0c0d 5:xxxx 6:xxxx 7:xxxx 2:0,3:0,4:0 qdiscs are just a trick to allow me to split main customer classes into 3 to 5 custom classes. I will use firewall filter co classify packets. The filter will be connected tto the root htb qdisc of device. Thanks to that I will create a low number of rules inside FORWARD chain of mangle table and so the load on my shaping boxes will decrease. I have discussed htb behaviour when used in complicated trees some time ago (on this list - thread: how htb treats priorities?) and I understand its behaviour. My question is ... are there any problems lurking inside this idea compared to my previous setup. Does an extra qdisc (no rate, no ceil, no prio) change htb behaviour described on pages of docum.org, especially link sharing rules? Is there a catch or everything will work as expected? Thx for you answers Robert Kryczalo