[PLUG] Network boot link died...

Michael Robinson plug_1 at robinson-west.com
Wed Mar 10 07:06:28 UTC 2010


On Tue, 2010-03-09 at 19:33 -0800, Neal wrote:
> Um, er, when we discussed this back in December it was pointed out
> that the total cabling limit for 100BASE-CX and 1000BASE-CX (STP) is
> 82 feet. Since you're also running an additional 100' of UTP in that
> segment you're pushing your luck even without cable degradation and
> the coupler in the run.
> 
> Temporarily replace the STP cable with an above-ground substitute and
> see if that clears things up.
> 
> NealS
> _______________________________________________
> PLUG mailing list
> PLUG at lists.pdxlinux.org
> http://lists.pdxlinux.org/mailman/listinfo/plug

If I understand the spec correctly for 100BaseTX, I should be fine.
The 90' cable is labeled as outdoor Cat 5e, though I wonder how 
long is this cable going to last?

I don't know what CX is and I'm not running a gigabit link, so the run
doesn't have to work at those speeds anyways.

Interestingly, turning off duplex and dropping the link speed to 10 mbps
stabilizes the link.  I noticed that duplex was set to full on the link
and that the link was unstable with that setting.

I suppose I can try a single run of UTP cable for the full 190'.  That
would eliminate the buried segment and the coupler as possible issues.
The first 100' of Cat 5e UTP cable could be the problem.

Trouble is, I have to bury the cable as that is the only practical way
to go.  Should I jump up to Cat 6 STP cable?  Is there a special cable
meant for direct burial that I should use?  How about burying the line
in conduit?  I've heard that UTP cable can be used if in conduit burial
is employed and moisture is kept out.

Let me assume that the limit isn't 300 meters, let's say the limit is
more like 82 feet.  Well, why didn't putting a 10/100 switch where 
the coupler is fix the can't transmit faster than 10 mbps problem?
Why was I able to buy a 100' Cat 5e UTP patch cable?




More information about the PLUG mailing list