TC Class confusion

[shane_mckinley]

I am building a Linux router to manage bandwidth to specific IP addresses.

Everything is working fine, but I am a little confused about the classes and how the hierarchy is working.

Example:

tc qdisc add dev eth0 root handle 1: htb default 12
tc class add dev eth0 parent 1: classid 1:1 htb rate 3mbit ceil 3mbit
tc class add dev eth0 parent 1:1 classid 1:10 htb rate 1mbit ceil 2mbit
tc class add dev eth0 parent 1:1 classid 1:11 htb rate 1mbit ceil 2mbit
tc class add dev eth0 parent 1:1 classid 1:12 htb rate 1mbit ceil 2mbit
tc filter add dev eth0 protocol ip parent 1:0 prio 1 u32 \
   match ip dst 0.0.0.0 flowid 1:12
tc filter add dev eth0 protocol ip parent 1:0 prio 1 u32 \
   match ip dst x.x.x.x flowid 1:11
tc filter add dev eth0 protocol ip parent 1:0 prio 1 u32 \
   match ip dst x.x.x.x flowid 1:10
tc qdisc add dev eth0 parent 1:10 handle 20: sfq
tc qdisc add dev eth0 parent 1:11 handle 30: sfq
tc qdisc add dev eth0 parent 1:12 handle 40: sfq

The only why the sfq commands would work is with the 20:, 30:, 40:, etc. What happens when I reach 90: ? Also, am I doing this efficiently? Any help is appreciated.

[cyberinstru]

Hi,

AFAIK, you can imagine these HTB Qs and classes as a tree.
1. Queue being the ROOT node
2. Classes are INTERIORS
3. SFQs (in your case) are LEAFs or EXTERIORS

I have a few questions on your Q hierarchy:

=>> Your max pipe size is 3Mbps. Then why is the CEIL values for its child classes configured as 2 mbit? Is it done intentionally?

=>> For further improving, classes can be prioritized.

20: 30: 40: are just HANDLE IDs. It can be any value. But the only condition is all the childs need to be properly attached to its parents.

HTH

[shane_mckinley]

The ceil is done intentionally, I was trying to make it 2mbit if it was available.

I would guess I would use prio X for prioritization?

And just to clear up the handle IDs on the sfqs, I can use any number except 1: ?

That was too simple, sorry for the waste of time...