NAS326 network speed issue

Could someone get 1Gb to work reliably?
When I'm trying to use NAS326 through wall outlet, it eventually starts spamming errors like this

2017-10-24T21:25:38+02:00 err kernel[]: [496485.750253] mvneta f1034000.ethernet eth1: bad rx status 0f810000 (crc error), size=938

https://forum.turris.cz/t/mvneta-ethernet-eth1-bad-rx-status/5479

Then it can show "cable may be defective" error and degrades to 100mbps.

If I'm connecting it directly to the router -> no errors in dmesg. But the problem still appears - after some time it switches from 1Gb to 100mbps.

I tried different cables and different hardware. The problem only appears with NAS326.

P.S. I didn't check what happen on the stock OS (I'll try when I get physical access to nas).

Relevant lines from dmesg:

[   24.675556] mvneta f1070000.ethernet eth0: PHY [f1072004.mdio-mii:01] driver [Marvell 88E1510] (irq=POLL)
[   24.694709] mvneta f1070000.ethernet eth0: configuring for phy/rgmii-id link mode
[   32.034004] mvneta f1070000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
[   47.589891] mvneta f1070000.ethernet eth0: Link is Down
[   47.724742] mvneta f1070000.ethernet eth0: PHY [f1072004.mdio-mii:01] driver [Marvell 88E1510] (irq=POLL)
[   47.736325] mvneta f1070000.ethernet eth0: configuring for phy/rgmii-id link mode
[   54.998759] mvneta f1070000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx

Previously it booted with 1Gbps with the same cable.
Also, I tried different kernels. The problem persists for the 4.20.x, 5.6.x and the latest 5.7.6

Linux nas 5.7.6-mvebu-tld-1 #1.0 SMP PREEMPT Mon Jun 29 14:13:34 PDT 2020 armv7l GNU/Linux

kekeke,

Sounds like the problem is with the your box NIC, i.e. hardware. I have not seen it on my NAS326. But let me check again sometime later today.

-bodhi
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kekeke,

See the bootlog by cyraxxx:

https://forum.doozan.com/read.php?2,104874,106264#msg-106264

So to see if it is not hardware, but something in your rootfs that cause this problem, post the serial boot log here.

-bodhi
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bodhi,
Thank you so much!
Will continue my experiments