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Topic: How do I set half-duplex mode on eth1?

The content of this topic has been archived on 24 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

Hi,

I have a problem where eth1 is stuck in full-duplex mode (it's only recently starting doing this, I don't know why), so I can't communicate with a device that uses 10baseT/Half.

Anyway here is the information I have for eth1 and the output from ethtool.


root@OpenWrt:/# dmesg | grep eth1
eth1: Broadcom 47xx 10/100BaseT Ethernet 00:0d:0b:47:ef:49
Probing device eth1: No Robo switch in managed mode found
Probing device eth1: No Robo switch in managed mode found
b44: eth1: Link is up at 100 Mbps, full duplex.
b44: eth1: Flow control is off for TX and off for RX.
b44: eth1: Link is up at 100 Mbps, full duplex.
b44: eth1: Flow control is off for TX and off for RX.

root@OpenWrt:/# ifconfig eth1
eth1      Link encap:Ethernet  HWaddr 00:0D:0B:47:EF:49
          inet addr:81.5.xxx.xxx  Bcast:81.5.xxx.xxx  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:4180449 errors:2 dropped:0 overruns:0 frame:1
          TX packets:1604 errors:0 dropped:0 overruns:0 carrier:42
          collisions:56 txqueuelen:1000
          RX bytes:4098703521 (3.8 GiB)  TX bytes:137612 (134.3 KiB)
          Interrupt:5

root@OpenWrt:/# ethtool eth1
Settings for eth1:
        Supported ports: [ MII ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Supports auto-negotiation: Yes
        Advertised link modes:  1000baseT/Full
        Advertised auto-negotiation: Yes
        Speed: 100Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 30
        Transceiver: external
        Auto-negotiation: on
        Current message level: 0x000000ff (255)
        Link detected: yes

root@OpenWrt:/# ethtool -s eth1 duplex half
Cannot set new settings: Invalid argument
  not setting duplex

(Last edited by norm360 on 24 Oct 2007, 06:58)

Try using the robocfg package.

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