BTW: This scenario's combination has another portion for us like as below. High Availability Server Clustering without ILB(Internal Load Balancer) (MEMO) http://slidesha.re/1vld6uB
-- Naoto MATSUMOTO On Mon, Feb 16, 2015 at 12:23 PM, NAOTO MATSUMOTO <[email protected]> wrote: > Hi Dan and ken. > > I respect your great works. > > Certainly, our scenario was network classics and it just does not "one > size fits all" network architecture. > Many people tried to built centralized and decentralized networks many > years ago, some guys output > implementation like this. > > > Interconnect of K computer (torus fusion) > > https://www.fujitsu.com/global/Images/fujitsu-hpc-roadmap-beyond-petascale-computing.pdf > > > I agree with you point. Our approach have to do more simple way on > physical and logical > network engineering, and change the mindset, I think. > (e.g. network cabling procedure and troubleshooting and handling) > > But, some guys need more cost effective server cluster environment and > they does't care > network latency like Low-End Web Hosting. > > > e.g. Intel Diversity of Server workloads http://bit.ly/1BgFH65 [JPG]. > > > Now, Many people do not use Dijkstra and automaton theory on the server > side, > but it is great mechanism for network durability if they controlled. > > The Ethernet NIC's bandwidth is increasing day by day, the cost is > decreasing too. > > I say again, our scenario is not "one size fits all" network architecture, > but we believe that something will happen for some guys works. ;-) > > best regards, > > -- > Naoto MATSUMOTO > > > > On Sat, Feb 14, 2015 at 7:08 AM, Dan Eckert <[email protected]> > wrote: > >> I'm having a hard time seeing how this reduces cable costs or increases >> network durability. Each individual server is well connected to 3-4 other >> servers in the rack, but the rack still only has two uplinks. For many >> servers in the rack you're adding 3-4 routing hops between an end node and >> the rack uplink. >> >> Additionally, with only 2 external links tied to 2 specific nodes, you >> introduce more risks. If one of the uplink nodes fails, you've got to >> re-route all of the nodes that were using it as the shortest path to now >> exit through the other uplink node -- the worst case in the example then >> increases from the original 4-hops-to-exit to now 7-hops-to-exit. >> >> As far as cable costs go, you might have slightly shorter cables, but far >> more complex wiring pattern -- so in essence you're trading off a small >> amount of cable cost for a higher amount of installation and >> troubleshooting cost. >> >> Also, using this layout, you dramatically reduce the effective bandwidth >> available between devices, since per-device links now have to be used for >> backhaul/transport in addition to device-specific traffic. >> >> Finally, you have to manage per-server routing service configurations to >> make this work -- more points of failure and increased >> setup/troubleshooting cost. In a ToR switch scenario, you do one config on >> one switch, plug in the cables, and you're done -- problems happen, you go >> to the one switch, not chasing a needle through a haystack of >> interconnected servers. >> >> If your RU count is worth more than the combination of increased >> installation, server configuration, troubleshooting, latency, and capacity >> costs, then this is a good solution. Either way, it's a neat idea and a >> fun thought experiment to work through. >> >> Thanks! >> Dan >> >> >> -----Original Message----- >> From: NANOG [mailto:[email protected]] On Behalf Of NAOTO MATSUMOTO >> Sent: Wednesday, February 11, 2015 11:32 PM >> To: [email protected] >> Subject: FYI: An Easy way to build a server cluster without top of rack >> switches (MEMO) >> >> Hi all! >> >> We wrote up TIPS memo "an easy way to build a server cluster without top >> of rack switches" concept. >> >> This model have a reduce switches and cables costs and high network >> durability by lightweight and simple configuration. >> >> if you interest in, please try to do yourself this concept ;-) >> >> >> An Easy way to build a server cluster without top of rack switches (MEMO) >> http://slidesha.re/1EduYXM >> >> >> Best regards, >> -- >> Naoto MATSUMOTO >> > >
