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mokku 10-21-2008 08:55 AM

auto negotiation question
server is runnnig half duplex, here is the result. Does it mean switch set to auto negoation or network card set to auto negotiation? Please help me.

>ethtool eth0
Settings for eth0:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
Supports auto-negotiation: Yes
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
Advertised auto-negotiation: Yes
Speed: 100Mb/s
Duplex: Half
Port: Twisted Pair
Transceiver: internal
Auto-negotiation: on
Supports Wake-on: g
Wake-on: d
Link detected: yes

chort 10-21-2008 09:02 AM


Advertised auto-negotiation: Yes
Auto-negotiation: on

Your card is set to auto-neg. Presumably so is the switch or it wouldn't have got a link.

mokku 10-21-2008 09:12 AM

Here is the /etc/sysconfig/ethconf file, does it need to set to auto or full duplex?

cat ethconf
# This file is read by /etc/init.d/ethconf shortly after the network
# is started. It is used to sets each NIC in the system according to
# the requirements of the network its on. The format of this file is
# as follows:
# DEVICE=<ifname>:<speed>[:duplex]
# where:
# <ifname> is eth0, eth1, etc.
# <speed> is 10, 100, or 1000, or auto
# <duplex> is half or full (or empty if auto is set)
# auto and 1000 are synonymous (the gigE standard requires auto-negotiation,
# and the interface and switchport will negotiate 1000 full-duplex)
# Here are some examples:
# DEVICE=eth0:auto
# DEVICE=eth1:100:full
# DEVICE=eth2:10:half
# If auto (or 1000) is not set, then the duplex must be specified or
# the script will continue without flagging an error.


chort 10-21-2008 09:32 AM


you missed an l.

Whether it needs 100:full or auto depends on your switch. How is the switch port configured?

mokku 10-21-2008 09:49 AM

Switch configured as full duplex

Port 1/26 100Full

Does it need to be auto or full ? Thanks in advance

There was a type it was configured as FULL, I just missed the L.

chort 10-21-2008 09:53 AM

Then your card should be configured for 100/full to match the switch. Either both sides should be auto, or both sides forced to the same speed and duplex.

I have no idea why the ethconf file isn't working if you don't have a typo. You can use ethtool to force the speed/duplex manually.

mokku 10-21-2008 03:15 PM

Thanks a lot for helping me out. When we do ethtool eth0, does it grep the information form ethconf and display the mode, such as auto or full duplex?

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