With 10 machines, if you want, you can just build 1 rack. What you might loose is rack awareness of Hadoop. Meaning all your data will be in one rack, so a rack lose is cluster loss.
Network topology depends on the following factors: 1. Your replication factor requirement for HDFS blocks 2. How much concurrency you want for Map task w.r.t failures, power and disk lose. 3. Also, your workloads plays a critical component - how much data is shuffled. Building a rack costs you money. Since you have only 10 machines, you can have one rack with a rack switch connected to all the nodes. My suggestion would be to take a phased approach: build - observe and iterate for your workload. -Bharath 2012/2/3 Jinyan Xu <[email protected]> > Hi Alex, sorry for my fuzzy description. > > I mean the physical link(network topological structure) for 10 machines. > > Thank you! > > -----Original Message----- > From: alo alt [mailto:[email protected]] > Sent: 2012年2月3日 15:56 > To: [email protected] > Subject: Re: 10 nodes how to build the topological graph > > Hi Rock, > > you mean rack awareness. > > http://hadoop.apache.org/common/docs/r0.17.2/hdfs_user_guide.html#Rack+Awareness > > Here you find examples: > http://wiki.apache.org/hadoop/topology_rack_awareness_scripts > > best, > Alex > > > -- > Alexander Lorenz > http://mapredit.blogspot.com > > On Feb 3, 2012, at 8:03 AM, Jinyan Xu wrote: > > > Hi , > > > > I have 10 machines to build a small cluster, how to build the > topological graph between these machines? > > > > I mean how to build the rack use 10 machines. > > > > Thanks ! > > > > -Rock > > > > ________________________________ > > The information and any attached documents contained in this message > > may be confidential and/or legally privileged. The message is > > intended solely for the addressee(s). If you are not the intended > > recipient, you are hereby notified that any use, dissemination, or > > reproduction is strictly prohibited and may be unlawful. If you are > > not the intended recipient, please contact the sender immediately by > > return e-mail and destroy all copies of the original message. > > > The information and any attached documents contained in this message > may be confidential and/or legally privileged. The message is > intended solely for the addressee(s). If you are not the intended > recipient, you are hereby notified that any use, dissemination, or > reproduction is strictly prohibited and may be unlawful. If you are > not the intended recipient, please contact the sender immediately by > return e-mail and destroy all copies of the original message. >
