The following command opens an ssh connection with the master instance in a cluster with the cluster ID ``j-3SD91U2E1L2QX``:: aws emr ssh --cluster-id j-3SD91U2E1L2QX --key-pair-file ~/.ssh/mykey.pem The key pair file option takes a local path to a private key file. Output:: ssh -o StrictHostKeyChecking=no -o ServerAliveInterval=10 -i /home/local/user/.ssh/mykey.pem hadoop@ec2-52-52-41-150.us-west-2.compute.amazonaws.com Warning: Permanently added 'ec2-52-52-41-150.us-west-2.compute.amazonaws.com,52.52.41.150' (ECDSA) to the list of known hosts. Last login: Mon Jun 1 23:15:38 2015 __| __|_ ) _| ( / Amazon Linux AMI ___|\___|___| https://aws.amazon.com/amazon-linux-ami/2015.03-release-notes/ 26 package(s) needed for security, out of 39 available Run "sudo yum update" to apply all updates. -------------------------------------------------------------------------------- Welcome to Amazon Elastic MapReduce running Hadoop and Amazon Linux. Hadoop is installed in /home/hadoop. Log files are in /mnt/var/log/hadoop. Check /mnt/var/log/hadoop/steps for diagnosing step failures. The Hadoop UI can be accessed via the following commands: ResourceManager lynx http://ip-172-21-11-216:9026/ NameNode lynx http://ip-172-21-11-216:9101/ -------------------------------------------------------------------------------- [hadoop@ip-172-31-16-216 ~]$