[Gllug] OT: What can take out a switch *and* an ethernet card?

[Ian Northeast]

Chris Bell wrote:
> On Thu 30 Sep, Ian Northeast wrote:
> 
> 
>>Can anyone explain this? Also, can anyone recommend the best place 
>>nowadays to get another 16 port 10/100 (I have a number of 10Mb devices 
>>which matter, like my firewall and my printer) switch?
>>
>>Regards, Ian
>>
>>
> 
>    I have not checked, but I suspect that the ethernet is not isolated from
> machine earth at either end, so could be affected by a floating earth
> connection. Many small hubs are supplied with a cheap external power adapter
> which is probably isolated, and only finds an earth as the mean of all its
> interconnections, but you should check that your workstation is well-earthed
> through its own mains cable. It may not be convenient, but it is a good idea
> to keep all the technical bits connected to the same earth point and
> unaffected by other more powerful equipment and inductive loads. The
> majority of my kit is even fed through the same spike filter.

I don't think that's *too* likely. The switch has an integrated power 
suppply and is fed by a 3 pin kettle lead (although I havn't checked 
whether the earth lead is actually present). They're not on the same 
wall socket but they are in the same room, and there's nothing in the 
room *except* computers etc. The next room just has the telly and the 
Hi-Fi, and the kitchen is at the opposite end of the house. The heating 
is gas. The house's electrical system is a bit dodgy, the previous owner 
was a builder who evidently also considered himself to be an 
electrician, a somewhat optimistic view. But a mate who really is an 
electrician has fixed the worst offenses. I havn't had any trouble with 
it lately.

Ian's suggestion seems more likely to me and the 8139 is headed to the 
bin. I had another one once, but I don't know where it's gone. I'll try 
to track it down and I'll replace it if I find it. Working in the IT 
department of a large company which is chucking out PIIs and not even 
bothering to strip them of the good bits, Intel Pro 100s are easy to 
come by.

I'm not entirely sure what the current status is. My lodger has 
evidently decided to try to fix it and both he and it have disappeared, 
and somewhat ominously in its place is a pair of wire strippers. No sign 
of a soldering iron though:) Well, it was buggered already, he can't 
make it worse. And he's been known to fix things I considered terminal 
in the past.

>    If you are near North Acton, 3A Distribution Ltd sell standard "no-name"
> switches
> 
> http://www.3adl.com
> 
> or you can mail-order through NetShop
> 
> http://www.NetShop.co.uk

I only see D-Links and Netgears on there - which are about the same 
price as I paid for the no-name 2 years ago. Which will do. Has anyone 
any opinion as to the relative merits of the two? I'll be wanting a 16 
port desktop type, and in the absence of any other consideration the 
D-Link looks more compact.

Going gigabit is a bit tempting given the prices - it'd only be about 
twice the price - but I don't think anything I've got here can really 
use it. My fileserver is an Ultra2 and I doubt if you can even get a 
gigabit S-Bus card and if you can the S-Bus is unlikely to be up to it. 
I like the Ultra2, I think the old Suns are much nicer than the new IDE 
based ones so I don't plan on replacing it any time soon. And while it 
may be a bit heretical so say so here, I believe that the NFS server in 
Solaris is still a lot better than the Linux one. The network - when the 
switch was working - was actually plentifully fast enough so gigabit 
would just be speed for its own sake. Something I generally use 
motorcycles for:)

Thanks to both you and Ian for your replies,

Regards, Ian




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