Web Hosting Talk : Web Hosting Main Forums : Hosting Security and Technology : Force full duplex, this how?

[Jeremy]

ifcfg-eth0

ETHTOOL_OPTS="speed 100 duplex full autoneg off"

then restart the network?

For some reason i totally forgot.. I'm getting some slow speeds on a Cisco 2900 switch (on the switch).

-dmesg-

eth0: network connection up using port A
    speed:           100
    autonegotiation: yes
    duplex mode:     half
    flowctrl:        none
    irq moderation:  disabled
    scatter-gather:  enabled

thx

[Jeremy]

hmm well that didn't work..

I did a full reboot dmesg shows the same, any ideas?

logs say this..

Dec 23 07:56:43 webby ifup: Cannot get current device settings: Operation not supported 
Dec 23 07:56:43 webby ifup:   not setting speed 
Dec 23 07:56:43 webby ifup:   not setting duplex 
Dec 23 07:56:43 webby ifup:   not setting autoneg

is it the switch?

MotherBoard Asus P4P-800-E Deluxe

[rustelekom]

on linux you can use mii-tools as i remember for check what happen with your nic (include his capabilities)

[DigitalN]

You can either as someone suggested use mii-tool

# mii-tool

No opitions, tells you the status of the link

# mii-tool eth0 -F 100baseTx-FD

will force 100Mb Full Duplex .. won't always work though

# mii-tool eth0 -A 100baseTx

Will advertise both full and half duplex. If your switch link is locked at half duplex, then you need to make the switch port full duplex as well.

You can use ethtool from command line too

# ethtool -s eth0 speed 100 duplex full autoneg off

or

# ethtool eth0

to see the supported options, no need to restart the network when changing the interface via mii-tool or ethtool.

# mii-tool

Will tell you where you are at and where you finish up.

[RSanders]

Both ends of the connection need to have the same setting. Set the switch to 100/full first then the machine. most of the time, auto does work well. If your switch is not set to auto right now try that first.

[cywkevin]

Auto negotiate can cause a lot of problems though. I agree with setting both sides as the above poster stated.

[RSanders]

Originally Posted by pixelized

Auto negotiate can cause a lot of problems though. I agree with setting both sides as the above poster stated.

Setting both sides also applies to 'auto'. most of the problems with using auto negotiate that I have seen is one side was not set the same.

You have a machine set to auto and the switch set to 100/full you may have problems.

[DigitalN]

The problems I have seen setting network connection parameters with mii-tool has been due to a crappy switch, that advertises either half or full duplex.. no autoneg

In these cases, ethtool saves the day by making your interface not try to autonegotiate. (mii-tool does not work in these cases I find)

So imho, you really need to look at your switch first, as that is likely the cause of the problem.

[Jeremy]

Hmmm the ports are forced 100mbps/fd.

i still get the error

Dec 23 07:56:43 webby ifup: Cannot get current device settings: Operation not supported 
Dec 23 07:56:43 webby ifup:   not setting speed 
Dec 23 07:56:43 webby ifup:   not setting duplex 
Dec 23 07:56:43 webby ifup:   not setting autoneg

[DigitalN]

What does

# mii-tool

reveal?

What is your switch set to?

[Jeremy]

[root@webby ~]# mii-tool eth0
SIOCGMIIPHY on 'eth0' failed: Bad address

also trying doesnt work

[root@webby ~]# mii-tool -F 100baseTx-FD eth0
SIOCGMIIPHY on 'eth0' failed: Bad address

NIC - Marvell Technology Group Ltd. 88E8001 Gigabit Ethernet Controller

my route table looks fine, i can shell in and out of it.

[Jeremy]

Thank you all for your help so far.

on the switch the command

show run

out puts this:

 interface FastEthernet0/9
 description LAX09-DM
 duplex full
 speed 100
 switchport access vlan 30
 spanning-tree portfast

dmesg

eth0: network connection up using port A
 speed:           100
 autonegotiation: yes
 duplex mode:     half
 flowctrl:        none
 irq moderation:  disabled
 scatter-gather:  enabled

-------

 divert: allocating divert_blk for eth0
 eth0: Yukon Gigabit Ethernet 10/100/1000Base-T Adapter
 PrefPort:A  RlmtMode:Check Link State

mii-tool - out puts

[root@webby ~]# mii-tool
SIOCGMIIPHY on 'eth0' failed: Bad address
no MII interfaces found

[DigitalN]

Try

# ethtool -s eth0 speed 100 duplex full autoneg off

Does that work for you?

Failing that, I would look at changing the switch port and then the network card interface.

[Jeremy]

[root@webby ~]# ethtool -s eth0 speed 100 duplex full autoneg off
Cannot get current device settings: Operation not supported
  not setting speed
  not setting duplex
  not setting autoneg

O no...

[DigitalN]

It might be best to try setting your switch to 'autonegotiate' rather than forcing full duplex, then set the interface to 'autonegotiate' too.

Try another network card if all fails, looks like your card doesn't want to be played around with, maybe a driver issue or just the card won't take the changes.
I'd try autonegotiate both ends, different switch port, then try another nic card.