Re: networking question
Jim Kinney <[email protected]> Wed, 19 Feb 2014 10:31:15 -0500
| Newsgroups | gmane.linux.redhat.k12osn |
|---|---|
| Message-ID | <CAEo=5PzO5FtVZjbsYpXjxOv5+Mf3H5HqGnDVkN5TDyhr6tBMpg@mail.gmail.com> |
I heard that story too and thought of Cobb county schools' aborted "Give 'em all a MAC" debacle. Given the poor fiscal support of schools in general, LTSP (and a next gen thing I'm still poking at) are the most cost effective ways to put students in front of computers for any reason. Next Gen Thing: server(s) runs Ovirt and many generic VMs. Student uses wireless android pad/laptop and connects using spice to get full desktop with sound and video. Memory usage is similar using memory ballooning (shared, read-only memory) as all VMs are identical. Drive space is similar (only /home is different for each) and it works over wireless and from home. Big advantage is 3-fold A) GUI for admin of VM environment (and user authentication using freeIPA has gui as well) B) better stability and security - student can only crash their VM, not the classroom or half the school. C) can use BYOD (mostly) as there is a spice client for windows, Linux, Mac and Android. I've found cheap android laptops for $100. tiny screen and keyboard but good size for little hands. Can still use this stuff for stand-alone machine lab setup by mounting /home from nfsv4 server. Good for video work. Most stuff needs minimal horsepower. Bigger kids can get bigger android laptops for $170. If schools could figure out how to use freetextbooks, the backpack load for the kids drops to 3-5 lbs. down from 20-40 lbs. Flash is still a hog. Wish it would go the way of the dodo bird. Wouldn't is be cool for kids to be able to say they use a supercomputer every day at school? !!! On Wed, Feb 19, 2014 at 10:03 AM, William Fragakis <[email protected]>wrote: > Jim, > (btw, hope all is well) big thanks to both you and Scott for your > exhaustive answers. > > We seem to be doing okay on the bandwidth internally, nothing is hanging > or lagging even with a few clients playing Pandora and a bunch of > internal rdesktop sessions. I think I'll downstream lower bandwidth > devices like printers, secondary vms, etc to a second inexpensive > switch. > > Off topic - heard on NPR how Los Angeles schools thought it would be a > good idea to get each student an iPad at about $700/device so they could > "all have computers". That was about the price of my latest kvm server > with an AMD 8 core CPU, 24GB RAM and 240GB SSDs in a RAID 1. Not to > mention the iPads are getting broken/stolen which makes the whole > process even more expensive. Not that we don't have iPads in our own > househould. Just that LTSP continues to make a ton of sense. > > again, my thanks and best regards to all, > William Fragakis > > > Message: 2 > > Date: Mon, 17 Feb 2014 13:04:01 -0500 > > From: Jim Kinney <[email protected]> > > To: "Support list for open source software in schools." > > <[email protected]> > > Subject: Re: [K12OSN] networking question > > Message-ID: > > <CAEo= > [email protected]> > > Content-Type: text/plain; charset="utf-8" > > > > my ordering for solution: > > > > 1) bigger switch (big assumption is existing network is not overloaded > now) > > 2) add a secondary "smart" switch above the existing switch if the > existing > > switch supports "upstream" port > > 3) add a second switch downstream with a bonded or aggregate connection > for > > more bandwidth (if "smart" primary switch) > > 4) add a secondary switch with Gbit upstream and 100M ports and set > primary > > switch to 100M except for new switch port > > 5) add a secondary switch upstream with bonded/aggregate connections to > > multiple nics on server > > 6) add a second switch off second nic on separate subnet and split the > > load. This requires a split subnet with dual gateways (each nic) (no > smart > > switch required) > > > > > > On Mon, Feb 17, 2014 at 10:30 AM, William Fragakis <[email protected] > >wrote: > > > > > Our k12linux installation is out-growing our present, very primitive, > > > networking structure. > > > > > > Currently, our ltsp server - which also behaves as the firewall for a > > > number of kvm servers and their vms - connects to 16 or so thin > clients. > > > Between the clients, internal servers and printers, the switch to which > > > the ltsp server is connected to is at capacity (It's a basic 24 port > > > gigabit). > > > > > > We now need to add the n+1 client that exceeds switch capacity. Do we > > > buy > > > a) a larger switch to replace the current one > > > b) a second switch daisy chained to the current one > > > c) a second switch connected to a second NIC using the same internal > > > ip/dhcp range (and if so, the recommended manner) > > > d) a more obvious, elegant, simple, cheaper method that I haven't > > > considered because I don't know squat (American slang for "not much") > > > about this stuff. > > > > > > thanks to all, > > > William Fragakis > > > > > > _______________________________________________ > > > K12OSN mailing list > > > [email protected] > > > https://www.redhat.com/mailman/listinfo/k12osn > > > For more info see <http://www.k12os.org> > > > > > > > > > > > -- > > > _______________________________________________ > K12OSN mailing list > [email protected] > https://www.redhat.com/mailman/listinfo/k12osn > For more info see <http://www.k12os.org> > -- -- James P. Kinney III Every time you stop a school, you will have to build a jail. What you gain at one end you lose at the other. It's like feeding a dog on his own tail. It won't fatten the dog. - Speech 11/23/1900 Mark Twain *http://heretothereideas.blogspot.com/ <http://heretothereideas.blogspot.com/>* _______________________________________________ K12OSN mailing list [email protected] https://www.redhat.com/mailman/listinfo/k12osn For more info see <http://www.k12os.org>