Duplex question - ifconfig output help



  • I'm trying to force the duplex on our WAN interface to 10 Mbps Full duplex using the command:

    
    ifconfig sk1 media 10baseT/UTP mediaopt full-duplex
    
    

    The output of ifconfig for the interface is now:

    sk1: flags=8847 <up,broadcast,debug,running,simplex,multicast>mtu 1500
    	options=b <rxcsum,txcsum,vlan_mtu>inet 10.10.96.3 netmask 0xffffff00 broadcast 10.10.96.255
    	inet6 fe80::20a:5eff:fe19:c5a1%sk1 prefixlen 64 scopeid 0x3 
    	ether 00:0a:5e:19:c5:a1
    	media: Ethernet 10baseT/UTP <full-duplex>(10baseT/UTP <half-duplex>)
    	status: active</half-duplex></full-duplex></rxcsum,txcsum,vlan_mtu></up,broadcast,debug,running,simplex,multicast> 
    

    Can someone please advice which media opt is actually active  there?  half or full duplex?

    Our provider has stated that the connection is 10Mbps full duplex.  And the company providing voice over it is saying we have to be sure we have that.  We have a few quality issues which they are saying is possibly because we have that duplex wrong.

    Bonus question:  If the ifconfig is saying we have half duplex how do I force it to go full?

    Thanks in advance.



  • I would do a " ifconfig -m sk1 " to see what it supports



  • Ok the output is:

    # ifconfig -m sk1
    sk1: flags=8847 <up,broadcast,debug,running,simplex,multicast>mtu 1500
    	options=b <rxcsum,txcsum,vlan_mtu>capabilities=b <rxcsum,txcsum,vlan_mtu>inet 10.10.96.3 netmask 0xffffff00 broadcast 10.10.96.255
    	inet6 fe80::20a:5eff:fe19:c5a1%sk1 prefixlen 64 scopeid 0x3 
    	ether 00:0a:5e:19:c5:a1
    	media: Ethernet 10baseT/UTP <full-duplex>(10baseT/UTP <half-duplex>)
    	status: active
    	supported media:
    		media autoselect
    		media 1000baseTX mediaopt full-duplex
    		media 1000baseTX
    		media 100baseTX mediaopt full-duplex
    		media 100baseTX
    		media 10baseT/UTP mediaopt full-duplex
    		media 10baseT/UTP</half-duplex></full-duplex></rxcsum,txcsum,vlan_mtu></rxcsum,txcsum,vlan_mtu></up,broadcast,debug,running,simplex,multicast> 
    

    So the card does what I want… but is it actually doing what I want?  Would I have to take down and bring back up the interface after changing the media options?



  • media: Ethernet 10baseT/UTP <full-duplex>(10baseT/UTP <half-duplex>)

    The part within () is what it is currently doing..  To the left of the () is what its configured for.

    Is the other side of the connection also set to 10-full?</half-duplex></full-duplex>



  • Mmm  :(

    I went and had a look at the Cisco Catalyst switch that our data providers says is definitely set to full duplex and sure enough the full duplex light shows up on that port (we don't get access to the console).


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