On Wed, May 19, 2010 at 6:43 AM, theluketaylor <[email protected]> wrote:
> Your idea to have 1 NIC for each of the switches to me sounds like the least
> fraught with peril (at least of the free options). In such
> a scenario bonding isn't the route you would want to take.
One switch per NIC is the simplest setup, but not the best performing,
assuming no money spent. In this setup, every client competes with 14
other clients for 100 mbps.
Alternatively, bond 3 NICs on a switch, then chain the switches. Now
12 clients compete for 300 mbps. 14 clients compete for 100 mbps, and
collectively for 300 mbps, while the 19 remaining clients (never mind
there's only 15 open ports on the switch) compete for 100 mbps,
collectively for what's left of 100 mbps from the second switch, and
then what's left of the 300 mbps from the first switch. In this
scenario, if every client is active, and assuming every port gets an
equal slice, the clients on the first switch each get 23 mbps, those
on the second switch get 1.5 mbps, and those on the third switch get
100 kbps.
The best-performing setup has 3 NICs bonded on the first switch with
the 2 remaining switches plugged into the first. Now you have 11
clients sharing 300 mbps, or 27 mbps each, and 30 clients sharing 54
mbps, or 1.8 each. You still have 4 clients without a link.
Ok, I admit that bandwidth doesn't get divided equally by port
normally, but bottlenecking a switch through 2 others upstream like
that will kill performance. The third solution paired with some QoS on
the server should actually be able to guarantee an equal share of
bandwidth to every active client, up to a limit of 100 mbps
collectively on the last 2 switches, and up to 300 mbps collectively
on the first switch, but you still have the problem of not enough
ports (you said you had 3 16-port switches, right?). The 2 prior
scenarios degrade less gracefully.
db
------------------------------------------------------------------------------
_____________________________________________________________________
Ltsp-discuss mailing list. To un-subscribe, or change prefs, goto:
https://lists.sourceforge.net/lists/listinfo/ltsp-discuss
For additional LTSP help, try #ltsp channel on irc.freenode.net
