KVM Switch

[alvin at Mail.Linux-Consulting.com]

hi 

and yes... good kvm are expensive...

we've found that cheap kvm sometimes does NOT work when you
switch between servers ... 
	- motherboard and mouse problem...

	- unplugging the mouse will sometimes/always hang the
	system if the wrong mouse is used on an incompatible motherboard
	( motherboard was D815EEAAL -- its a good mb )

	- in that case... you have to have a good kvm that
	maintains electrical connectivity to the mouse ports
	when switching between servers

	- we discarded all the belkin kvm due to the above issues
	and bought a different brand... ( i've forgotten which one 
	as i dont work with that client any more )

have fun linuxing..
alvin


On Fri, 11 May 2001, Robert G. Brown wrote:

> On Fri, 11 May 2001, Raghubhushan Pasupathy wrote:
> 
> > Folks,
> >
> > I am looking to buy a KVM switch for an 8-node(16 processor) Beowulf
> > Cluster. Can anyone give me some directions on this since I am completely
> > lost. What specs, brand etc. do you suggest?
> 
> Why?  KVM's tend to be very expensive (I know, I have a Raritan which is
> an excellent choice and even keyboard-switchable BUT which costs a whole
> lot -- good KVM's can cost $100 per port or even more).  I also have a
> really cheapo four position mechanical KVM switch that works for
> keyboard and video but cannot switch PS2 mice.  It degrades video
> quality a bit but is fine for my simple home beowulf, where I have two
> or three systems that do a bit of server stuff and hence need a console.
> 
> Nowadays a cluster node can run anywhere from totally headless (Scyld, I
> believe, is happy enough with no head at all), headless but a serial
> port console (a VERY cheap option that is probably adequate for
> debugging a dying boot and which can be switched with a cheap serial
> switch or managed via a still not very expensive serial port server),
> headless but with a cheap video card that one plugs into a monitor one
> time (to set the bios and monitor the original install) and then never
> again, headed but no X (X plus a GUI is quite expensive in memory and
> moderately expensive in wasted CPU), and headed running X.  I now have a
> $3000 KVM switch that is more useful for switching between servers
> (where one really does sometimes need access to a console) than between
> beowulf nodes, which one generally accesses over the net anyway.
> 
> I personally generally go with cheap S3 cards (or any sort of onboard
> video if the motherboard happens to have it) and no X just to make it a
> bit faster to set up the systems and debug them if/when they break.  The
> one hassle of running a system with no video card at all is that one
> often has to put one in long enough to set up the bios, in particular to
> tell the bios to run without a video card without complaining (which
> most BIOS's do these days if you ask nicely).  Is the time saved worth
> the $30 the card costs per system?  Don't know, but it's close...
> 
>    rgb
> 
> >
> > Raghu
> > _________________________________________________________________
> > Get your FREE download of MSN Explorer at http://explorer.msn.com
> >
> >
> > _______________________________________________
> > Beowulf mailing list, Beowulf at beowulf.org
> > To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
> >
> 
> -- 
> Robert G. Brown	                       http://www.phy.duke.edu/~rgb/
> Duke University Dept. of Physics, Box 90305
> Durham, N.C. 27708-0305
> Phone: 1-919-660-2567  Fax: 919-660-2525     email:rgb at phy.duke.edu
> 
> 
> 
> 
> _______________________________________________
> Beowulf mailing list, Beowulf at beowulf.org
> To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
>