William:
As mentioned, do be sure to
a) add the server’s public key to root’s “authorized_keys” on your node
b) as root, run the “ssh localhost” command and answer “yes” to any questions about unknown server keys, etc. to ensure “localhost” is part of known_hosts
c) ensure the permissions on ~root/.ssh are 700 and on ~root/.ssh/authorized_keys is 600
d) when installing the cluster, use “localhost” as the server address; otherwise, you must perform step 2 for the hostname or IP you do use
If the above fails, it may be helpful to run an ssh command as if it were running remotely, or the scp command, while using the -v option to show verbose output. This might assist in understanding why Ambari’s passwordless access may be failing. Sample commands might look something like this
# ssh -vv host.domain.example.com /bin/date
# scp -vv /var/tmp/some.file.txt root@host.domain.example.com:/var/tmp/some.file.transfered.txt
Happy hadooping,
Bryce Ryan