Defective ethernet on ReadyNAS 202

[erik_liland]

I'm having a RN202 which I lost connection to, and after a lot of debugging I found that it was the Ethernet on the RN202 that was the problem. I have attached the boot log (via UART).

After serial login I get the following errors in dmesg over and over again: 

[ 468.295048] al_eth_0 mdio read failed on error. phy_addr 0x4 reg 0x5
[ 468.315084] al_eth_0 mdio read failed on error. phy_addr 0x4 reg 0x5
[ 468.335051] al_eth_0 mdio read failed on error. phy_addr 0x4 reg 0x5
[ 468.355039] al_eth_0 mdio read failed on error. phy_addr 0x4 reg 0x5
[ 468.375043] al_eth_0 mdio read failed on error. phy_addr 0x4 reg 0x5
[ 468.395046] al_eth_0 mdio read failed on error. phy_addr 0x4 reg 0x5
[ 468.415069] al_eth_0 mdio read failed on error. phy_addr 0x4 reg 0x5
[ 468.435037] al_eth_0 mdio read failed on error. phy_addr 0x4 reg 0x5
[ 468.455038] al_eth_0 mdio read failed on error. phy_addr 0x4 reg 0x5
[ 468.475067] al_eth_0 mdio read failed on error. phy_addr 0x4 reg 0x5
[ 468.494972] al_eth 0000:00:01.0 eth0: MDIO read failed on timeout

And if I run 'ip -a' I get:

root@Hafslund_4TB:~# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000
link/ether a0:63:91:65:4b:f0 brd ff:ff:ff:ff:ff:ff
3: eth1: <BROADCAST,MULTICAST,DYNAMIC> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether a0:63:91:65:4b:f1 brd ff:ff:ff:ff:ff:ff
4: LeafNets: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1400 qdisc pfifo_fast state UNKNOWN group default qlen 1000
link/ether 8a:96:d6:11:33:0f brd ff:ff:ff:ff:ff:ff
inet 5.251.2.75/8 brd 5.255.255.255 scope global LeafNets
valid_lft forever preferred_lft forever
inet6 fe80::8896:d6ff:fe11:330f/64 scope link
valid_lft forever preferred_lft forever

For all I can understand it looks like a dead ethernet chip.

Any ideas on the cause of this problem would be highly appreciated.