[nycbug-talk] Noob networking question

Charles Sprickman spork at bway.net
Fri Jul 21 00:06:23 EDT 2006

On Thu, 20 Jul 2006, Marco Scoffier wrote:

> Hello all,
> I have a FreeBSD 6.0 atalk (networking for Macintosh) server in a small
> office, and I am getting radically different speeds, from different
> machines (all 100T ethernet connections) even at night when I know I am
> the only one doing anything on the network.

As Pete said, the first thing to check is duplex mismatches - in short it 
causes packet loss, and packet loss slows down TCP bigtime - it never gets 
a chance to "ramp up" to full speed.

> The slowness seems more obvious using appletalk, because to copy a 500MB
> file from one machine to the shared disk took a minute, to copy it from
> the server, behind the switch the copy was asking for several hours.
> And copying it from the server to another machine took 24mins.

Are the machines with differing speeds all Macs?  Different models of 
Macs?  Different versions of OS-X?

> Question 2) I have a few machines off a switch (linksys 100 baseT) which
> is connected through the uplink port and a crossover to the main
> router/firewall/gateway netgear.  Machines connected to this switch
> (which is new) seem much much slower than the rest.  Is there anything
> I can do about this ?

Perhaps that's your problem right there, you might have a duplex mismatch 
between the switches, or just a bum cable connecting them.

I also have PR open on OS-X<->FreeBSD tcp slowness, but IIRC it's just in 
4.x and only with a handful of the cheapy network cards...


> A little bit lost here, things just ain't workin' like they should,
> Thanks for any pointers,
> -- 
> Marco
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