queue simple drop packet - how to fix that?

RouterOS General
1

Hi.
I have one router which is connect to my backbone by 100Mbit/s channel.
However I would like to limit one customer on that router to 30 Mbit/s.
This customer has specific p-2-p traffic that is around 25-30Mbit full-duplex.
So , I’ve create smple q for that:
[admin@xxx] /queue simple> print
Flags: X - disabled, I - invalid, D - dynamic
0 name=“LAN” dst-address=x.x.x.x/27 interface=LAN parent=none direction=both priority=8 queue=ethernet-default/ethernet-default limit-at=0/0 max-limit=30M/30M burst-limit=0/0 burst-threshold=0/0 burst-time=0s/0s total-queue=ethernet-default
[admin@xxx]

I this case the customer has packet drop.
Can anybody give me suggestion how to better limit such kind of speed to avoid packet drops?

2

Increase the queue limit…

It sounds like he’s hitting the threshold and packets are being queued too long and thus dropped. Check the stats for the simple queue.

3

What about limit-at=0/0 ? Is it Ok for such speeds?
I use ethernet-default (kind=pfifo pfifo-limit=50) to shape this customer.
Is it ok for 30Mbit/s shape?

4

Wiki says:

Every packet that cannot be enqueued (if the queue is full), is dropped. Large queue sizes can increase latency, but utilize channel better.

Set pfifo-limit=500 and observe results.

Regards,

5

Thx.

What about limit-at=0/0 ?
Should I set it to half of max-limit ?
I mean: does limit-at=15M “help me” in case if i use max-limit=30M ?

6

Hi,

‘limit-at’ is CIR in MT naming convention. It means that data rate is guaranteed to a target.
In your case with limit-at=15M and max-limit=30M customer has guaranteed bandwith 15Mb/s and 30Mb/s maximum when bandwith is available.
P2P opens a lot of connections, so IMHO you should also set pfifo-limit=500 as I wrote earlier,
or define new SFQ type queue for this customer only. Make some test and let me know how it works.

HTH,

7

ok, thx.
Will try.