AmpLab Big Data Benchmark for Spark error on EC2 - amazon-ec2

Question

I am trying to run the Big Data benchmark on my EC2 cluster for my own Spark fork located here. It just modifies some files on the Spark core. My cluster contains 1 master and 2 slave nodes of type m1.large. I use the ec2 scripts bundled with Spark to launch my cluster. The cluster launched perfectly and I am able to successfully ssh into the master. However when I try to run the benchmarks from the master using the command
./runner/prepare-benchmark.sh --shark --aws-key-id=xxxxxxxx --aws-key=xxxxxxxx --shark-host=<my-spark-master> --shark-identity-file=/root/.ssh/id_rsa --scale-factor=1
I get the following error:
=== IMPORTING BENCHMARK DATA FROM S3 ===
bash: /root/ephemeral-hdfs/bin/hdfs: No such file or directory
Connection to ec2-54-201-169-165.us-west-2.compute.amazonaws.com closed.
bash: /root/mapreduce/bin/start-mapred.sh: No such file or directory
Connection to ec2-54-201-169-165.us-west-2.compute.amazonaws.com closed.
Traceback (most recent call last):
File "./prepare_benchmark.py", line 606, in <module>
main()
File "./prepare_benchmark.py", line 594, in main
prepare_shark_dataset(opts)
File "./prepare_benchmark.py", line 192, in prepare_shark_dataset
ssh_shark("/root/mapreduce/bin/start-mapred.sh")
File "./prepare_benchmark.py", line 180, in ssh_shark
ssh(opts.shark_host, "root", opts.shark_identity_file, command)
File "./prepare_benchmark.py", line 139, in ssh
(identity_file, username, host, command), shell=True)
File "/usr/lib64/python2.6/subprocess.py", line 505, in check_call
raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command 'ssh -t -o StrictHostKeyChecking=no -i /root/.ssh/id_rsa root#ec2-54-201-169-165.us-west-2.compute.amazonaws.com 'source /root/.bash_profile;
/root/mapreduce/bin/start-mapred.sh'' returned non-zero exit status 127
I have tried terminating the cluster and launching it again multiples times but the problem persists. What could be the issue?