QOS: Shaping traffic with priorities and variable ADSL bandw

WiFiStudent · June 26, 2004, 4:15pm

The setup below is working fine, but I have a 2-8mbps ADSL line and my bandwith is variabel between 2mbps and 8mbps.

The setup below works like a great, but only when Max-Limit of Queue ALL-DL < Current ADSL speed.

I could set Max-Limit to a low value that’s always true, but offcourse I would like to bennefit from my highspeeds when possible.

I the ADSL speed drops below the specified Max-Limit of All-DL then MT doesn’t shape as it is supposed to do. It just tries to distributes the traffic evenly.

Any suggestions ?

Queue HighPriority has Priority set to 1
Queue LowPriority has Priority set to 8

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Eugene · July 2, 2004, 10:54am

You need to specify limit-at value as the lowest possible ADSL line speed.

WiFiStudent · July 2, 2004, 3:45pm

Thanks for your reply !

I tried your suggestion but it didn’t have the result I was hoping for. I set Limit at 1mbits. I started a download job in the Low Priority Queue, this job is taking 100% of the bandwith. Then I started a Second download job in the High Priority Queue. The result can be seen with the included image. If MT is shaping correct, then the low priority queue wil drop to Limit At (100kbps). But it doesn’t. It still tries to distribute the traffic evenly between the Low and High queue. Again when I specify Max Limit of All-Dl below my current max bandwith, then it’s shape just as it should. The speed of LowPriority Queue then drops to 100kbps.

Any other suggestions ?

Thanks in advance !

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wjw · July 3, 2004, 2:58am

What priority is each queue set to?

WiFiStudent · July 3, 2004, 10:53am

High P is set to 1
Low P is set to 8
The rest is set to default 8

wjw · July 3, 2004, 11:23am

hmm well maybe you could set the secondary high queues to 7, that may help… the other option is that it could be something to do with the firewall mangle rules.. I had issues with trying to get a set of IP’s running at 5mbps when accessed locally and 1mbps when remote… fidled with accept/passthrough and that fixed it…

Eugene · July 4, 2004, 12:59pm

can you connect to your router with telnet and post printouts from
/ip firewall mangle export
and
/queue export
commands?

WiFiStudent · July 4, 2004, 9:25pm

I tried to set inner queue’s to priority 7, but this did not have any effect.

Again thanks for all your efforts uptil now!

Here are the exports from my mangle queue setup:

/ ip firewall mangle
add src-address=:119 in-interface=Internet protocol=tcp action=accept
mark-flow=DL-NNTP comment=“” disabled=no
add in-interface=Internet p2p=all-p2p action=accept mark-flow=DL-P2P
comment=“” disabled=no
add src-address=:80 in-interface=Internet protocol=tcp action=accept
mark-flow=DL-HTTP comment=“” disabled=no
add src-address=130.89.1.223/32 in-interface=Internet flow=!P2P
action=accept mark-flow=UT-VPN comment=“” disabled=no
add in-interface=Internet action=accept mark-flow=DL-AllOther comment=“”
disabled=no

================================

/ queue type
set default name=“default” kind=pfifo bfifo-limit=15000 pfifo-limit=50
red-limit=60 red-min-threshold=10 red-max-threshold=50 red-burst=20
sfq-perturb=5 sfq-allot=1514 pcq-rate=0 pcq-limit=50
pcq-classifier=“”
set ethernet-default name=“ethernet-default” kind=pfifo bfifo-limit=15000
pfifo-limit=50 red-limit=60 red-min-threshold=10 red-max-threshold=50
red-burst=20 sfq-perturb=5 sfq-allot=1514 pcq-rate=0 pcq-limit=50
pcq-classifier=“”
set wireless-default name=“wireless-default” kind=sfq bfifo-limit=15000
pfifo-limit=50 red-limit=60 red-min-threshold=10 red-max-threshold=50
red-burst=20 sfq-perturb=5 sfq-allot=1514 pcq-rate=0 pcq-limit=50
pcq-classifier=“”
set synchronous-default name=“synchronous-default” kind=red
bfifo-limit=15000 pfifo-limit=50 red-limit=60 red-min-threshold=10
red-max-threshold=50 red-burst=20 sfq-perturb=5 sfq-allot=1514
pcq-rate=0 pcq-limit=50 pcq-classifier=“”
/ queue tree
add name=“All-DL” parent=global-out flow=“” limit-at=1000000
queue=ethernet-default priority=8 max-limit=8000000 burst-limit=0
burst-threshold=0 burst-time=0 disabled=no
add name=“LowPriority” parent=All-DL flow=“” limit-at=100000
queue=ethernet-default priority=8 max-limit=8000000 burst-limit=0
burst-threshold=0 burst-time=0 disabled=no
add name=“News” parent=LowPriority flow=DL-NNTP limit-at=0
queue=wireless-default priority=8 max-limit=0 burst-limit=0
burst-threshold=0 burst-time=0 disabled=no
add name=“P2P” parent=LowPriority flow=DL-P2P limit-at=0
queue=wireless-default priority=8 max-limit=0 burst-limit=0
burst-threshold=0 burst-time=0 disabled=no
add name=“HighPriority” parent=All-DL flow=“” limit-at=8288608
queue=ethernet-default priority=1 max-limit=8288608 burst-limit=0
burst-threshold=0 burst-time=0 disabled=no
add name=“HTTP” parent=HighPriority flow=DL-HTTP limit-at=0 queue=default
priority=8 max-limit=0 burst-limit=0 burst-threshold=0 burst-time=0
disabled=no
add name=“UT” parent=LowPriority flow=UT-VPN limit-at=0
queue=wireless-default priority=8 max-limit=0 burst-limit=0
burst-threshold=0 burst-time=0 disabled=no
add name=“Rest” parent=HighPriority flow=DL-AllOther limit-at=0
queue=default priority=8 max-limit=0 burst-limit=0 burst-threshold=0
burst-time=0 disabled=no

Eugene · July 5, 2004, 7:53pm

First of all, non-leaf queues do not contain priority information.
Consequently, you need to change your flowmarks to get 1 flowmark for HighPriority queue and 1 flowmark for LowPriority queue.
You should also note, that the router is trying to satisfy limit-at for child queues first.

Applying all forementioned information to your case we need to configure the following queues:

/ queue tree
add name=“All-DL” parent=global-out flow=“” limit-at=1000000
queue=ethernet-default priority=8 max-limit=8000000 burst-limit=0
burst-threshold=0 burst-time=0 disabled=no

add name=“LowPriority” parent=All-DL flow=“LowPriorityFlow” limit-at=500000
queue=ethernet-default priority=8 max-limit=4000000 burst-limit=0
burst-threshold=0 burst-time=0 disabled=no

add name=“HighPriority” parent=All-DL flow=“HighPriorityFlow” limit-at=300000
queue=ethernet-default priority=1 max-limit=4000000 burst-limit=0
burst-threshold=0 burst-time=0 disabled=no

The (approximate!!!) order of satisfying various limits will be as follows:

limit-at for HP
limit-at for LP
limit-at for AD
1000000 (AD limit-at) - 300000 (HP limit-at) - 500000 (LP limit-at) = 200000 → max-limit of one of child chains
max-limit for AD
max-limits of child chains (not more, than AD max-limit)