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MP2 GX Ethernet networking issues

Dear all,

I'm trying to set up a brand-new Multiplus 2 48/5000/70 GX. Alas, I'm having severe networking issues when connecting to the GX device, firmware v2.89. It seems to me as if the GX nanopi has problems receiving IP packets on the cabled Ethernet connection.

DHCP did not work for me. DHCP requests arrived at the DHCP server, which also answered, but answers were somehow ignored by the GX device. So I assigned a static IP address manually through the Wifi-accessible web interface.

But even with the static IP address I cannot reliably ping the GX device. On the one hand, the GX answers all Ethernet (TCP/IP layer 2) fragments at a 100% success rate (I'm using arping for tests), so I can exclude a cable problem. I also should note I tried two well-tested cables.

Then again, the GX device has severe problems when receiving IP packets. Only about one out of hundred ICMP (IP) packets will be answered. Surprisingly, the packet counts that ifconfig shows do not increase even though they should. It seems packets are somehow lost before the GX's nanopi sees them.

Only the receiving side is affected. Sending IP packets works reliably.

I have not tested to configure Wifi access. I'm a bit hesitant doing so as I don't want to loose the MP's access point, which is my only way to configure the device right now.

Is this a known issue? If so, can I do anything at the software layer to resolve this issue, or is this a hardware issue?

Multiplus-IIgx device
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linuxfr33k answered ·

I found the problem: The economy mode of my Netgear switch seem to have disabled the cable plug (except the few success cases I saw). I speculate that the economy mode is disabled for ARP requests, but gets active for IP packets. Anyways, after having disabled eco mode for the plug, the packet loss was gone. I'll drop this here in case somebody has a similar problems and seeks for a solution.

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mvader (Victron Energy) avatar image mvader (Victron Energy) ♦♦ commented ·
Hi thanks for that update! You got me worried for a moment there.


Matthijs

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linuxfr33k avatar image linuxfr33k mvader (Victron Energy) ♦♦ commented ·

Yeah I can imagine. I noticed that also other Nanopi users experienced similar issues, which is why I tried this step. Frankly, none of the other 20+ devices in my house has similar issues, also not RaspPis. I guess the Nanopi sends with too low power. Why its ARP segments always get through, while IP packets don't, remains a miracle for me, though.

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