Adam,<br><br>Many thanks for these suggestions.<br><br>
<div class="gmail_quote"><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">Can you manually examine the config on the switch? It's possible there<br>
is some residual config left somewhere, perhaps the use of VLANs which<br>
restrict access to certain switch ports.<br></blockquote><div><br>I can. And I have done. There doesn't seem to be anything causing a problem. And since I've tried two switches, it would be highly coincidental with them both stopping the same thing. And if I connect to the same port of the managed switch that doesn't work with a client, via a normal dumb switch, LTSP works fine.<br>
<br></div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<br>
Other than that, Gb ethernet uses all 4 pairs on an ethernet cable,<br>
unlike 10 and 100 MB, which only use 2 pairs. As a result, as Alex<br>
suggested, 100 Mb will often work on cables with broken pairs, where Gb<br>
ethernet exposes the fault and won't work.<br></blockquote><div><br>I take this point. But the ports that I am trying to use are the 100M ports. <br><br></div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
The only other thing I can think is maybe your clients are failing to<br>
auto-negotiate the speed setting when 1GB is available. </blockquote><div><br>When my daughter suggested this, I thought it the most likely issue. It does seem to be almost something at a hardware level since putting a dumb switch between the non-working client and the managed switch makes the client work. So, obviously, everything necessary is getting through the managed switch. <br>
<br>I also thought that it couldn't be a problem with spanning tree, which I did try disabling, but it made no difference. If spanning tree had been a problem, it would have been so even with the dumb switch in place. <br>
<br>The managed switch ports were initially set to auto and I moved them to
100M to check the issue of negotiation. No improvement.<br>
<br> </div><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">This seems<br>
unlikely to be honest but you could check it by booting your thin<br>
clients from a live CD or USB stick and using ethtool when attached to<br>
the Gb switch, e.g.:<br></blockquote><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
ethtool eth0<br>
<br>
It's possible that you might need to install ethtool inside the live CD<br>
environment depending on what you use, which is do-able but not when<br>
your switch doesn't work ;)<br>
<br></blockquote><div>This is a good idea. There are one or two ideas to try first, but I'll put this on the list. <br> <br></div></div>I am going to try a different network card and see if it is a problem with the onboard NIC. <br>
<br>After that I am scratching around. (LTSP does not like blue? The managed switch is blue. Try painting the managed switch the same colour as the dumb switch?.........)<br><br>The bottle of champagne is still going.<br>
<br>Mark<br><br><div style="visibility: hidden; left: -5000px; position: absolute; z-index: 9999; padding: 0px; margin-left: 0px; margin-top: 0px; overflow: hidden; word-wrap: break-word; color: black; font-size: 10px; text-align: left; line-height: 130%;" id="avg_ls_inline_popup">
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