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Troubleshooting

How To Find Hard Disk SATA Link Speed On FreeBSD

I know how to find out my SATA link speed such as 3.0 or 6.0 Gbps on Linux operating system. How do I find out my SATA link speed on FreeBSD Unix operating system? How do I make sure my sata hard disk is working at 6Gbps speed and how do I verify this on a FreeBSD server hardware?
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Sysadmin because even developers need heroes!!!

How to find out information about a LXC (Linux container) CPU & Memory Usage

How can I find out information about a Linux container (LXC) such as CPU usage and memory usage from the command prompt? Is there is top command like a tool for lxc to monitor memory and cpu usage?
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FreeBSD Unix Find Out Which Programs Are Listening On a Given Port Number

I‘m a new FreeBSD Unix system user. How can I find out the process/programs names listing on a certain port on a FreeBSD Unix systems using command line? How do I lookup the process which is currently bound to the given network port on a FreeBSD server?
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Use ssh-copy-id with an OpenSSH Server Listening On a Different Port

My OpenSSH server listening on TCP port number 2222. How can I use ssh-copy-id with an sshd server with listening on a different port on a Linux or Unix-like systems?
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I need to tunnel X Window securely over SSH bases session so that I run X program on my remote Linux/Unix server/workstation and get back display to my Apple Macbook pro laptop. I tried the ssh -X user@server1 and ssh -Y user@server2 commands on both OS X Mountain Lion and Apple OS X Mavericks/Yosemite. But, I am unable to use the ssh command with X11.

How do I fix this problem on OS X and enable X11 forwarding with ssh command? How do I install XQuartz (X11.app) server on Apple OS X Mountain Lion or Mavericks or Yosemite?
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I‘m installing FreeBSD 10 Xorg and xfce4 desktop. But, getting the following error:

(EE) Failed to load module “fbdev” (module does not exist, 0)

How do I fix this problem on FreeBSD 10 amd64 based system?
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Linux / Unix – crontab: no crontab for user using an empty one error and solution

I am trying to set cronjob on a Unix systems by running the crontab -e command. But, I’m getting the following error:

crontab: no crontab for veryv – using an empty one
crontab: “/usr/bin/vi” exited with status 1

How do I fix this issue on a Linux or Unix-like systems?
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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 1.2.3.4

How do I fix “X11 forwarding request failed on channel 0” on Linux or Unix-like systems?
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CentOS: rpmdb: PANIC: fatal region error detected; run recovery error and solution

I am using a CentOS Linux v6.5 on my home server and I am getting the following error when I execute yum command:

rpmdb: PANIC: fatal region error detected; run recovery
error: db3 error(-30974) from dbenv->open: DB_RUNRECOVERY: Fatal error, run database recovery
error: cannot open Packages index using db3 – (-30974)
error: cannot open Packages database in /var/lib/rpm
CRITICAL:yum.main:

Error: rpmdb open failed

How do I fix this problem on a CentOS / RHEL based system?
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