InstaGENI rate limitation.

[Gholam Reza Rahimi]

Hi all,

Does anybody know how link rate are actually limited?

For example, I reserved two bare metal nodes in the same rack and then I limited the link rate between them to 20Mbps. I checked all the traffic control commands assigned to network interfaces, but I couldn't find anything related to this limitation. I just want to know where the GENI administrators implement assigned bit rates to links.

Regards,

Reza

[nriga]

Hi Reza, 

I am sorry for the late reply. Could you be a bit more specific on what you did to test this? To the best of my knowledge there is not way to change the rate of a link between your nodes AFTER the reservation unless if you use some type of software in your node (e.g. tc). 

Do you want to know how the rate is set between nodes at reservation time? 

--niky

[Nicholas Bastin]

On Thu, Aug 13, 2015 at 11:37 AM, Gholam Reza Rahimi <rahim...@gmail.com> wrote:

Does anybody know how link rate are actually limited?

For example, I reserved two bare metal nodes in the same rack and then I limited the link rate between them to 20Mbps. I checked all the traffic control commands assigned to network interfaces, but I couldn't find anything related to this limitation. I just want to know where the GENI administrators implement assigned bit rates to links.

On bare metal nodes the traffic shaping is generally implemented using the linux traffic control ('tc') facility. which you actually can control after the fact, although the configuration can be fairly obtuse.

--

Nick 

[Leigh Stoller]

> On bare metal nodes the traffic shaping is generally implemented using the linux traffic control ('tc') facility. which you actually can control after the fact, although the configuration can be fairly obtuse.

This is also true for VMs, the implementation is the same. You can
look in /var/emulab/boot/rc.linkdelay for all of the commands that
install the traffic shaping.

Leigh