Anyone know of a program that would detect pinout of remote end of cable?

CodeBloxCodeBlox Member Posts: 1,363 ■■■■□□□□□□
I can't find the specs for my cable modem anywhere but I suspect it's not able to properly establish a connection with my 1721 and 2950 because of MDI-X... I cannot find any doc that details what pins my modem ethernet port tx/rx on. Can anyone suggest a program that would give me this info? That way I can make a cable to the spec.
Currently reading: Network Warrior, Unix Network Programming by Richard Stevens

Comments

  • CodeBloxCodeBlox Member Posts: 1,363 ■■■■□□□□□□
    icon_sad.gif No replies... I might have to just get a cable tester to get the info I need... I know the ones at work tell me what pins are in use.
    Currently reading: Network Warrior, Unix Network Programming by Richard Stevens
  • MentholMooseMentholMoose Senior Member Member Posts: 1,524 ■■■■■■■■□□
    ethtool will show this. Most laptop NICs do auto MDI-X, so connect a laptop running a recent Linux distribution to your modem and run ethtool.
    MentholMoose
    LFCE - MCITP: EDA7, VA, SA, EA - MCSA:S 2003 - CCA (PVS 5, XD 3 / 4 / 5, XS 5 / 6) - VCP 4 / 5
  • SteveO86SteveO86 Member Posts: 1,423
    Not sure if the 2950 supports this but I know the 2960 series do.

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  • CodeBloxCodeBlox Member Posts: 1,363 ■■■■□□□□□□
    I'll have a look at ethtool. Thanks!

    Steve - The 2950s do not support MDI-X
    Currently reading: Network Warrior, Unix Network Programming by Richard Stevens
  • EV42TMANEV42TMAN Member Posts: 256
    how do you have the router interface set up for the cable modem? i just installed an 1841 at home and i had to set it to pppoe to get it to work
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  • CodeBloxCodeBlox Member Posts: 1,363 ■■■■□□□□□□
    The only thing I configured on the router was the ip addressing (DHCP), speed, duplex, and NAT. It immediately gives a flashing orange light when plugging in. I then took the 2950 and plugged it in and got the same blinking orange light. I know that neither of these devices support mdix which is leading me to believe it's the cause. Once I get my hands on a cable tester, I can make a cable with what I believe will be the correct pinouts and see if it works.

    Since my 1721 only has one Fast Ethernet interface, I'll be using router on a stick. I'll connect my switch to the modem as an access link and trunk the switch to the router giving it a DHCP acquired address on a subinterface. I have disabled STP on the link to the modem as well as CDP. I really believe the cable is the problem.
    Currently reading: Network Warrior, Unix Network Programming by Richard Stevens
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