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M4300-96X occasional packet loss

MarsKeeper
Aspirant

M4300-96X occasional packet loss

We have 18 devices connected to the M4300-96X with PoE mode, the devices are kept running always. However, we found there are occasional packet loss, the probability is about one packet loss every three days. We prefere to regard it as normal. However, we want to get more technical explanation:

Is there any relevant standard define the requirement of the PLR (packet loss rate) on 10GbE network?

Model: XSM4396K0/XSM4396K1|M4300-96X – Modular Managed Switch
Message 1 of 9
schumaku
Guru

Re: M4300-96X occasional packet loss

Packets are not lost in the switch - much more on the links. Typical cause for packet loss are bit errors, caused by poor SNR, insufficient power allocation on an optical link, insufficient link bandwidth, jitter, baseline wander, ..

 

By wally brain, IEEE states 1*10^-10 for the acceptable BER on a 1000M link. Some discussions were around on 1x10^-13 for the acceptable BER on 10G links.

 

@LaurentMa do you have any more information at hand?

Message 2 of 9
MarsKeeper
Aspirant

Re: M4300-96X occasional packet loss

Hi Schumaku:

 

Thanks for your reply!

 

I still have some addtional questions:

1. In the experiment, the devices are powered by PoE mode and it seemed that the PoE budget (capacity) is very critical because the PoE MAX indicator lit on occasionally. As the worst situation, some devices even rebooted because the power was not enough.

Do you think the insufficient PoE power may lead error packet on the 10G copper link?

2. Could you tell me the No. of the IEEE specification about the BER? If you do not remember the exact No. a rough range would be helpful for us.

 

Thanks!

Model: XSM4396K0/XSM4396K1|M4300-96X – Modular Managed Switch
Message 3 of 9
schumaku
Guru

Re: M4300-96X occasional packet loss


@MarsKeeper wrote:

1. In the experiment, the devices are powered by PoE mode and it seemed that the PoE budget (capacity) is very critical because the PoE MAX indicator lit on occasionally.


What kind of PoE devices are we facing here? Any tech data or references available?

 

For completeness, provide the config (modules, power supplies) of the M4300-96X please.

 


@MarsKeeper wrote:

As the worst situation, some devices even rebooted because the power was not enough.

Do you think the insufficient PoE power may lead error packet on the 10G copper link?


If the device powered does not get enough power (e.g. when it's exceeding the negotiated and speced power) anything can go wrong with the clients... This might have an impact on the 10G link. Crash recovery is the worst case happening.

 


@MarsKeeper wrote:

2. Could you tell me the No. of the IEEE specification about the BER? If you do not remember the exact No. a rough range would be helpful for us.


Hm by rule of old cells 802.3ab for Gigabit Ethernet .. don't shoot me 8-)

 

 

Message 4 of 9
MarsKeeper
Aspirant

Re: M4300-96X occasional packet loss

The powered deice is developed by ourselves, it is not meaningful to discuss its model because you can not purchase it on the market now. It is a PoE+ device, the switch has the below configuration:

1200W PSU   x1

APM408C      x3

APM408P      x3

APM408F      x2

We found that if the connected devices is more than 20, some devices may reboot repeatedly and the PoE MAX led light on occcasionally. We calculated the PoE budget according the manual and the result said that it was enough.

In fact, I have requsested a support ticket to solve this problem but the process is slow because we are busy on another things recently.

I will check the IEEE document to get the BER specification.

 

Thank you very much!

Model: XSM4396K0/XSM4396K1|M4300-96X – Modular Managed Switch
Message 5 of 9
schumaku
Guru

Re: M4300-96X occasional packet loss

That's what I assumed kind of - 10G PoE+ devices putting PD and and modular switch to the limits things to the limit don't exist that many.

 

Based on the calculation, your set-up is well within the specs, but hey I'm just yet another Netgear user and customer (and a little bit technology geeky needless to say). Have some sites with much more APM408P in action with PoE+ and 2.5/5G links - piece of cake compared to what you are heading to. Multigig is less power hungry than 10G, and the access points don't draw much more than what a basic PoE level would be able to deliver. The fact that the PoE Max LED does show up does certainly indicate something is not working right in the set-up, and I don't wonder your devices are power starving when this happens.

 

There might be ways to get more insight of the M4300-96X chassis power system and from the APM408P which might be helpful for you as well as for Netgear. The product line manager for these switches @LaurentMa is called herewith, this is something for you to handle svp.!

Message 6 of 9
LaurentMa
NETGEAR Expert

Re: M4300-96X occasional packet loss

Hi there,

 

Yes, of course. If the PoE Max LED is sometimes up, it means that something is exhausting the PoE budget in the switch. Yes in that case PoE will be shut on some ports provoking packet loss in the interval, likely.

 

If the devices shouldn't exhaust the PoE budget, it means that something is wrong in their PoE advertisement maybe - not presenting their class correctly, which leads the switch to allocate more PoE power than needed.

 

I would look into that first, the PoE pages in the GUI will show the PoE classes etc. Alternatively, the PoE method can be changed in the switch, to accommodate such special problem, but it would be better to make sure the PD devices (PoE powered devices) advertize correctly.

 

Please try to reproduce this issue (wait until you see it happen again), and export the Tech-Support file from the switch at that time. Maintenance\Export\HTTP File Export and select tech-support in the dropdown menu. Please send us your tech-support file at ProAVDesign@netgear.com and we'll take a look for you.

 

Regards,

Laurent Masia
NETGEAR Senior Product Line Manager, Managed Switches
Message 7 of 9
MarsKeeper
Aspirant

Re: M4300-96X occasional packet loss

Hi Laurent,

 

We did export a tech-support file after the problem occurred on 28th,Nov. However, I can not post it here because of the forum bans .txt attachment. 

I can not access dropbox from China mainland either, could you tell me your mailbox so that I will send the file by E-Mail?

 

Thanks & Regards!

Model: XSM4396K0/XSM4396K1|M4300-96X – Modular Managed Switch
Message 8 of 9
LaurentMa
NETGEAR Expert

Re: M4300-96X occasional packet loss

Yes this is a text file that can be sent by email and you can send it to ProAVDesign@netgear.com

Thanks!
Regards,
Laurent Masia
NETGEAR Senior Product Line Manager, Managed Switches
Message 9 of 9
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