Anthony, > In regards to different locations of the HADOOP home this is low > priority more for testing not production. I was trying to install HADOOP > for testing over 2 machines with only a Windows XP machine running > Cygwin and a Mac running Darwin. Not a priority. > > In regards to my last question about operating in a detached fashion, we > are trying to factor in what happens when the link between both sites is > cut. Will both sites operate independently until the connection is > re-established? Is there any particular setup required to ensure we can > cover this scenario or is it an out-of-the-box feature?
When you say 'sites', do you mean two different Hadoop installations ? In general, each site is independent. So, I am unable to understand where the link comes in. > > Anthony > > > -----Original Message----- > From: Hemanth Yamijala [mailto:[email protected]] > Sent: Tuesday, 25 May 2010 12:08 PM > To: [email protected] > Subject: Re: Active-Active Performance > > Anthony, > > I'm new to Hadoop and I've been given the task to see how we might > utilise >> Hadoop and HBase to implement an Active-Active site layer for sharing >> information across a distributed application. >> >> >> >> I've been able to: >> >> * Install and get Hadoop running on a single node and am in > the >> process of configure a 2 node setup. >> >> * Install HBase on a single node and create a table and > mapping as >> well as insert data into the system >> >> >> >> Once I've got the mutli-node configured I hope to run some tests as > well. >> >> >> >> I've noticed that trying to start Hadoop in distributed mode, the > slave >> will ssh to the master to start it as well (bin/start-all.sh) provided > the >> same path is setup on the remote machine. >> >> >> >> Questions: >> >> Can I configure the system IF the Hadoop installation is not in the > same >> location per machine? >> > > I would think configuring and managing such a system would get very > complex > - for e.g. if you'll want to add nodes to expand in future. You would > also > not be able to take advantage of the very helpful scripts that come with > Hadoop. Is there a reason why you want to do this ? > >> If the master node goes down (say due to electrical fault or system > fault) >> how do the slave nodes react? Will they continue to run? Will the > nodes be >> back in sync once the master starts again? >> > > Hadoop slaves will continue. They will enter a retry loop trying to > connect > to the master until it comes up. In doing so, they could fill up log > files > very fast though. If the master starts with the same configuration, > (same > host, ports), they should be able to connect and resume. > >> Would I require a particular configuration to ensure that both our > sites >> can operate within the cluster as well as in a detached fashion (due > to >> maintenance or network issues)? >> >> >> > I did not quite follow this. Can you explain a little more about how you > want to setup your system ? > > Thanks > Hemanth > > _____________________________________________________________________ > This e-mail has been scanned for viruses by MCI's Internet Managed > Scanning Services - powered by MessageLabs. For further information > visit http://www.mci.com > > ********************************************************************** > This e-mail message and any attachments are intended only for the use of the > addressee(s) named above and may contain information that is privileged and > confidential. If you are not the intended recipient, any display, > dissemination, distribution, or copying is strictly prohibited. If you > believe you have received this e-mail message in error, please immediately > notify the sender by replying to this e-mail message or by telephone to (02) > 9646 9222. Please delete the email and any attachments and do not retain the > email or any attachments in any form. > ********************************************************************** >
