I tried following the instructions for a single-node cluster (as mentioned
in the link). I am facing a strange roadblock.
In the hadoop-site.xml, I have set the value of hadoop.tmp.dir to
After doing this, I run bin/hadoop namenode -format, and this now creates a
hadoop-sridhar folder at under workspace. This is fine as the user I've
logged on as is "sridhar".
Then I start my cluster by running bin/start-all.sh. When I do this, the
output I get is as mentioned in this
but a new folder called hadoop-SYSTEM is created under workspace.
And then when I run bin/stop-all.sh, all that I get is a "no tasktracker to
stop, no datanode to stop, ...". Any idea why this can happen?
Another point is that after starting the cluster, I did a netstat. I found
multiple entries of localhost:9000 and all had LISTENING. Is this also
On Wed, Apr 23, 2008 at 9:13 PM, Norbert Burger wrote:
Yes, this is the suggested configuration. Hadoop relies on password-less
SSH to be able to start tasks on slave machines. You can find
on creating/transferring the SSH keys here:http://www.michael-noll.com/wiki/Running_Hadoop_On_Ubuntu_Linux_%28Multi-Node_Cluster%29
On Wed, Apr 23, 2008 at 4:39 AM, Sridhar Raman wrote:
Ok, what about the issue regarding the users? Do all the machines need to
be under the same user?
On Wed, Apr 23, 2008 at 12:43 PM, Harish Mallipeddi <
On Wed, Apr 23, 2008 at 3:03 PM, Sridhar Raman <
After trying out Hadoop in a single machine, I decided to run a MapReduce
across multiple machines. This is the approach I followed:
(A doubt here: Can my Master also be used to execute the Map/Reduce
If you add the master node to the list of slaves (conf/slaves), then
master node run will also run a TaskTracker.
To do this, I set up the masters and slaves files in the conf
sshd in both the machines, and was able to ssh from one to the
I tried to run bin/start-dfs.sh. Unfortunately, this asked for a password
for user1@slave, while in slave, there was only user2. While in
user1 was the logged on user. How do I resolve this? Should the
accounts be present in all the machines? Or can I specify this
circos.com : poundbang.in/blog/