[NTLUG:Discuss] Solved, Thanks.-> what is the problem?

m m llliiilll at hotmail.com
Wed Jul 31 08:40:41 CDT 2002 

Hi All:
Thanks you all for the advice.
The problem was I did not use a standard EIA/TIA A/B cable.
I custom made it as punchdowns (BLOG scheme), and it didn't work.
After I re-make the cable, it works.
Thanks a lot.


>From: "Paul Ingendorf" <pauldy at wantek.net>
>Reply-To: discuss at ntlug.org
>To: <discuss at ntlug.org>
>Subject: RE: [NTLUG:Discuss] what is the problem?
>Date: Tue, 30 Jul 2002 18:06:34 -0500
>
>This could be a number of issues including line inductance causing the nway 
>negotiation to have some issues negotiating a proper connection resulting 
>in something that could look like massive collisions on that segment.  One 
>way to test this would be to try the two hubs together going from a regular 
>port on switch a to the uplink on switch b using a straight through cable 
>sans the receptacles and see if the link light is steady.
>
>-----Original Message-----
>From: discuss-admin at ntlug.org [mailto:discuss-admin at ntlug.org]On Behalf
>Of m m
>Sent: Tuesday, July 30, 2002 9:34 AM
>To: discuss at ntlug.org
>Subject: Re: [NTLUG:Discuss] what is the problem?
>
>
>Thanks for you all.
>
>Here is more detail:
>switch A is SMC (8 ports), switch B is Trendware (4 ports).
>This time I just try switch A anb B. (leave switch C alone)
>Switch A connect to router and other PCs, all works fine.
>If I use Switch B connect to router and other PCs, all works fine, too.
>the connection diagram:
>router
>   |
>   |        cable A   cable B   cable C
>[switch A]---------O---------O---------[X]
>                    ^         ^
>                    |         wall receptacle
>                  inline receptacle
>
>cable A and B is custom made straight-thru cable,  use BLOG color scheme.
>cable A connect to switch A regular port:
>1. use cable c (straight-thru) connect to [x] (x=PC), works fine. the PC 
>can
>through the internet.
>2. use cable c (straight-thru ) connect to [x] (x=switch B, uplink port),
>the light is blinking, indicates collusion.
>3. use cable c (straight-thru ) connect to [x] (x=switch B, regular port),
>no lights on switch B is on, it doesn't work.
>4. use cable c (crossover) connect to [x] (x=switch B, uplink port), the
>light is on, it seems all connected, but the PC connected to this switch 
>(B)
>cannot go through the internet. PCs connect to this switch talks. but not
>talk to PCs on switch A.
>5. use cable c (crossover) connect to [x] (x=switch B, regular port),
>no lights on switch B is on, it doesn't work.
>I don't think connect switch A (uplink port) to any port of switch B is a
>correct way to do connection. (through I tried, all failed)
>
>thanks.
>
>
>
>
>
>
>
>
> >From: "Chris J Albertson" <alb at chrisalbertson.com>
> >Reply-To: discuss at ntlug.org
> >To: <discuss at ntlug.org>
> >Subject: Re: [NTLUG:Discuss] what is the problem?
> >Date: Mon, 29 Jul 2002 12:12:03 -0400 (EDT)
> >
> >You've done a lot of the debugging I would have done to this point.
> >When connecting switches, it's either regular port to uplink via
> >straight-thru cable... or regular port to regular port via cross-over
> >cable.
> >Since You're doing the regular port on switch A to uplink on B, you have 
>a
> >straight-thru. If it works when you just replace switch B with a PC, then
> >I'd say switch A and the straight-thru cable work fine.
> >Now, if you get the same results with switch C uplink port, I would have
> >to say that you've got something wrong with the uplink configuration of
> >switches B and C. I doubt switch A has anything to do with this, nor do I
> >think it's the cable.
> >One thing I would do for sure is remove all devices from all the 
>switches.
> >If these are truly switches as you say, then you have some software
> >configuration to start looking at. You may have some virtual LAN setups 
>or
> >such going on. I dunno.
> >Another thing to try is to get switches B and C talking. If you can get
> >those switches to connect, then start adding devices to them. You may
> >find, as mentioned by someone else, that your cable modem is hurting you.
> >
> >In my experience with getting switches and hubs to talk on the same
> >subnet, bad uplink connections usually identify themselves with no link
> >light at all. This is the puzzling part.
> >
> >Good luck!
> >
> >Chris
> >
> >
> >Kelledin said:
> > > Your cable modem should be connected directly to a router, not
> > > sitting on a switch.  Having it sitting on your network like
> > > just another networked PC may work, it may not.  Even if it
> > > seems to work, it may force certain limitations.  If PCs on
> > > Switch A are able to reach PCs on Switch B (and vice versa), but
> > > not all of them can use the cable modem, this is likely to be
> > > your problem.  Your solution in this case would be to set up a
> > > router (preferably Linux on an old 486 with two Ethernet cards).
> > >
> > > If PCs on Switch A are _not_ able to reach PCs on Switch B, then
> > > you need to check a few things:
> > >
> > > 1) See if disconnecting the cable modem allows the two switches
> > > to work properly together.
> > > 2) See if the uplink port being used requires a crossover
> > > connection (versus the more standard straight-through).  Some
> > > 10baseT and Fast Ethernet switches require this; copper Gigabit
> > > switches should not.
> > > 3) Make sure the uplink port being used is actually set to work
> > > as an uplink port.  Most switches have a setting that can force
> > > the uplink port to work just like any other port.
> > >
> > > On Monday 29 July 2002 01:33 pm, m m wrote:
> > >> Hi All:
> > >>
> > >> I have a problem on internet connection, please help.
> > >>
> > >> switch A connect to cable modem, switch A is about 100-150
> > >> feet aparts for PCs and switch B. the connection cable are two
> > >> cat5 with inline receptacle. I can connect from network switch
> > >> A to any of my PCs, it works. I use the same wire to connect
> > >> to network switche A (regular) to Switch B (uplink), it does
> > >> not work. the switch A light is on (indicate good), the switch
> > >> B uplink light is blinking (indicates collusion) I use the
> > >> same wire to connect to network switche A (uplink) to Switch C
> > >> (regular), it does not work either. the switch A, the switch B
> > >> lights are blinking (indicates collusion)
> > >>
> > >> any one have a clue?
> > >>
> > >> thanks.
> > >>
> > >>
> > >> ______________________________________________________________
> > >>___ MSN Photos is the easiest way to share and print your
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> > >>
> > >> _______________________________________________
> > >> http://www.ntlug.org/mailman/listinfo/discuss
> > >
> > > --
> > > Kelledin
> > > "If a server crashes in a server farm and no one pings it, does
> > > it still cost four figures to fix?"
> > >
> > > _______________________________________________
> > > http://www.ntlug.org/mailman/listinfo/discuss
> >
> >
> >
> >
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