Linux & Windows Tips, Tutorials, , Ideas

Proxmox/OpenVZ Can’t umount (unmount) device or resource busy

proxmox Recently when working on an OpenVZ container I was attempting to create a backup.  While doing so I kept running into a problem where the server wouldn’t let me unmount the container in order to create the backup.  The error you may see in this instance would say “Can’t umount /var/lib/vz/root/OpenVZID device or resource busy”, or “Can’t umount /var/lib/vz/root/100: Device or resource busy TASK ERROR: command ‘vzctl umount 100’ failed: exit code 51″, in this case the container being 100.  Here’s how I was able to fix it …

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How to Changing a file’s “Date Created” and “Last Modified”

faqHow to Changing a file’s “Date Created” and “Last Modified”

you can use the touch command along with the -r switch to apply another file’s attributes to a file.

NOTE: There is no such thing as creation date in Unix, there are only access, modify, and change. See this U&L Q&A titled: get age of given file for further details.

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How to resolve “Account creation failed” related errors in cPanel when creating account

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Everyone has come across the frustraiting and annoying issue of trying to create an account and receiving an error during installation relating to the account creation failed existing already. The errors can vary but are all along the same lines: User already exists, This system already has a database owner named <blank>, etc etc. There are a million tutorials on this, but almost all of them lack all of the steps needed to fully remove an account with this problem. This usually happens because you were trying to previously create an account and stopped the process before letting it finished, or a backup restoration didnt completely finish and left remnants of the account behind.

 

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Block Port With IPtables

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How do I block port number with iptables under Linux operating systems?

Port numbers which are recognized by Internet and other network protocols, enabling the computer to interact with others. Each Linux server has a port number (see /etc/services file). For example:

 

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A New DDoS Reflection Attack: Portmapper; An Early Warning to the Industry

dos-attack

The faster those of us in the security and network operator space can detect a new attack vector, the faster we can come up with ways to slow or stall the growth of that method. To accomplish this, Level 3 monitors threat indicators across our network and looks for trends in attacks that we mitigate for our customers. We are also in a unique position as a global backbone operator to often see multiple stages of the attack, not just the final stage targeting the victim. This allows us to block ….

 

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How to make WHM & cPanel configuration

cpanelwhm

Note: If you haven’t installed cPanel & WHM on your server yet, you may follow How to install WHM & cPanel on CentOS 6 Linux server to learn how to install cPanel & WHM on Linux CentOs server.
After you have done your cPanel & WHM installation on your server, you may access your control panel via https://youripaddress:2087 address. You should make some configuration for your first run.

 

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