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I‘m a new Unix system user. How can I manage process on a FreeBSD operating systems?
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Connect To Amazon AWS EC2 Instance From a CentOS / RHEL Using SSH Client

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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Fix: /bin/dbus-launch terminated abnormally without any error message and solution

I am a new Linux server user. I need to tunnel X over ssh. I type the following command on a CentOS/RHEL based remote host to get display on a local desktop:

ssh -X user@server1.cyberciti.biz
xeyes &
firefox &

But, I am getting an error that read as follows:

**error**: Failed to contact configuration server; some possible causes are that you need to enable TCP/IP networking for ORBit, or you have stale NFS locks due to a system crash. See http://projects.gnome.org/gconf/ for information. (Details – 1: Failed to get connection to session: /bin/dbus-launch terminated abnormally without any error message)

How do I fix this error on a newly formatted/installed RHEL or CentOS Linux 6.x server?
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X11 forwarding request failed on channel 0 Error and Solution

I am a new Linux server user. I need to tunnel X over ssh. I type the following command from OS X Unix terminal to login into far_away_machine (a centos server):

ssh -X -o options -A -p 22 user@centos-far-away-server

But, I am getting the following error on screen:

X11 forwarding request failed on channel 0
Last login: Sun Mar 23 15:58:51 2014 from

How do I fix “X11 forwarding request failed on channel 0” on Linux or Unix-like systems?
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How To Setup SSH Keys on a Linux / Unix System

I recently read that SSH keys provide a secure way of logging into a Linux and Unix-based server. How do I set up SSH keys on a Linux or Unix based systems? In SSH for Linux/Unix, how do I set up public key authentication?
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CentOS Linux 5/6: Change OpenSSH Port Number

I am a new CentOS Linux user. How do I change default sshd tcp port # 22 to 2022 on CentOS Linux version 5/6?
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OpenBSD: Reload / Restart / Stop dhcpd Server Command

I manage MS-Windows server and recently started to play with OpenBSD server. How do I reload or restart the dhcpd server on OpenBSD using shell command line option?
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Change Password Using passwd Command Over SSH Based Session

I‘m a new Ubutnu Linux user. I backup files to our corporate Unix backup server using the rsync command. The server only allow to upload/download files. I am unable to login to the server. How do change my password using the passwd command over ssh based session?
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OpenSSH Config File Examples

How do I create and setup an OpenSSH config file to create shortcuts for servers I frequently access under Linux or Unix desktop operating systems?
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OpenBSD: Mount An ISO Image Command

How do I mount an ISO image in OpenBSD operating systems using command line options?
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