I have created/launched Amazon Machine Image (AMI) instance powered by a CentOS/RHEL/Red Hat Enterprise Linux. How can I connect to my instance using OpenSSH Linux/Unix/OSX ssh client?
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I am a new Unix shell programer. How can I extract the directory name from a full path (say /nas01/data/backups/file.tar.gz)? How do I get directory name from its path on a Linux or Unix-like system?
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I am a new Linux user. I use scp to upload files to net-storage provided CDN company. I do not want to overwrite the existing files. How can I prevent overwriting of files when using scp command under Linux, Mac OS X or Unix like operating systems?
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I am a new vi / vim text editor user and I know how to quit without saving changes. What if I want to wipe out all of the edits I have made in a session and get back to the original file? How do I wipe all changes since opening a file?
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How do I use rsync command to sync files to a remote host called web-42.vps running VSFTPD ftp server? Can you give me rsync ftp example for Unix like operating systems?
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I‘m setting up server on an Amazon EC2 compute instance powered by Suse Enterprise Linux server. I am using the following command to login into the my EC2 compute from Mac OS X/Ubuntu Linux desktop:

ssh -i suse-ec2-server-jp.pem root@ec2-xx-yy-zzz-yyy.compute-1.amazonaws.com

I am getting the following error:
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: UNPROTECTED PRIVATE KEY FILE! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
Permissions 0440 for 'suse-ec2-server-jp.pem' are too open.
It is recommended that your private key files are NOT accessible by others.
This private key will be ignored.
bad permissions: ignore key: suse-ec2-server-jp.pem
Password:

How do I fix this problem and login using ssh command?
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