Audience
This article is for experienced Linux users who are familar with environment variables such as
$HOME and $USER. These are the Linux users who are familiar with the
command line.
Problem and Solution
Here is an example not to use /home/$USER:
[gpeddie-games@epcotcenter ~]$ su - gpadmin
Password:
mkdir: cannot create directory ‘/home/gpadmin’: Permission denied
touch: cannot touch '/home/gpadmin/Templates/Text file': No such file or directory
mkdir: cannot create directory ‘/home/gpadmin’: Permission denied
-bash: /home/gpadmin/.local/share/DaVinciResolve/configs/.version: No such file or directory
Welcome. All activities monitored at all times.
Unauthorized access is strictly prohibited.
gpadmin@epcotcenter
~
$
And here's the script (/etc/profile) that illustrates an example:
# fix gnome missing 'New file' option
if [ ! -f /home/$USER/Templates/"Text file" ]
then
mkdir -p /home/$USER/Templates
touch /home/$USER/Templates/"Text file"
fi
# ...
# this is a hack to bypass the Davinci Resolve new install Welcome/Onboarding screen since it does not render properly and is not required.
if [ ! -f /home/$USER/.local/share/DaVinciResolve/configs/.version ];then
mkdir -p /home/$USER/.local/share/DaVinciResolve/configs/
echo "Onboarding.Version=10" > /home/$USER/.local/share/DaVinciResolve/configs/.version
fi
To fix this issue, simply replace all instances of /home/$USER with $HOME.
I am familiar with a text editor called Vim. It's a program that runs inside a terminal, similar to the
Command Prompt or PowerShell in Windows.
Before we proceed any further, let's create a backup copy of /etc/profile:
sudo cp /etc/profile /etc/profile.bak
If anything goes wrong, you now have a backup. You can simply use the cp (copy) command to
restore from the backup. Now let's begin.
First, open the Terminal (Konsole in KDE).
As root (or with sudo privileges), type the following command:
sudo vim /etc/profile
Type in the following command, starting with a colon:
:%s/\/home\/$USER/$HOME/g
The syntax for search and replace in Vim is as follows:
:%s/search/replace/g
Let's not concern ourselves with g at the end for now. Basically this command replaces
"search" with the next text "replace." In other words, we want to replace /home/$USER with
$HOME.
Let's have a look at the script again:
# fix gnome missing 'New file' option
if [ ! -f $HOME/Templates/"Text file" ]
then
mkdir -p $HOME/Templates
touch $HOME/Templates/"Text file"
fi
# ...
# this is a hack to bypass the Davinci Resolve new install Welcome/Onboarding screen since it does not render properly and is not required.
if [ ! -f $HOME/.local/share/DaVinciResolve/configs/.version ];then
mkdir -p $HOME/.local/share/DaVinciResolve/configs/
echo "Onboarding.Version=10" > $HOME/.local/share/DaVinciResolve/configs/.version
fi
So why would we want to replace /home/$USER with $HOME? That
/home/$USER should still work!
Let's look at the output again after we save the changes.
Save the changes to the /etc/profile file.
:wq
A : begins a command. w writes changes to the file and q
quits Vim
If you don't want to make changes to the file, then all you have to do is type :q! to
exit without saving any changes.
As I mentioned, let's look at the output again when I log into my administrator account from a user
account.
[gpeddie-games@epcotcenter ~]$ su - gpadmin
Password:
mkdir: cannot create directory ‘/home/gpadmin’: Permission denied
touch: cannot touch '/home/gpadmin/Templates/Text file': No such file or directory
mkdir: cannot create directory ‘/home/gpadmin’: Permission denied
-bash: /home/gpadmin/.local/share/DaVinciResolve/configs/.version: No such file or directory
Welcome. All activities monitored at all times.
Unauthorized access is strictly prohibited.
gpadmin@epcotcenter
~
$
Now, let's see the new output when I log back in as an administrator.
[gpeddie-games@epcotcenter ~]$ su - gpadmin
Password:
Last login: Sat Mar 18 11:13:52 EDT 2023 on pts/0
Welcome. All activities monitored at all times.
Unauthorized access is strictly prohibited.
gpadmin@epcotcenter
~
$
I have covered more explanation regarding
how this works and I have discussed a scenario in my article.
Article published: 2023-03-18 15:37
Categories: The World of Computers, Computers, Information Technology, Scripting and Programming
Audience and Prerequisites
Skip to scenario if you want to jump into the main article.
This is for anyone who currently host their WordPress or ClassicPress in a virtual private server such as DigitalOcean, Linode, or any other VPS providers. Any Linux user with knowledge of command line can perform backups and restoration tasks. You must be familiar with Linux and you know how to connect to your production server via SSH.
Plus, this article assumes that you have installed and configured WordPress in your VPS server. In addition, this article assumes you can perform basic database administration tasks such as adding a new database along with creating a new user for WordPress or ClassicPress. If your hosting provider provides managed WordPress or ClassicPress hosting, then this article may not apply to you. And because this article is for those who currently run a VPS server, I am going to have to assume that you have some hands-on experience with the Linux command line. This article need not apply to non-technical Linux, Mac, and Windows users. When I say non-technical Linux users, I'm talking about those who wanted to get away from Windows or Mac and simply wanted to use Linux just to browse the Internet and not deal with the command line.
Last, but not least, I am also going to assume that you know how to configure your Apache server as well. Both Apache and NGINX (pronounced Engine-X) configurations won't be covered here, including backing up and copying certificates that you get from your hosting provider.
If you are interested in learning Linux, a tutorial from Guru99 will help get you started on learning Linux.
Are you ready? Then let's get started!
Scenario
You have your own VPS server that is running ClassicPress. Your domain name is exmaple.com and your SSH port number is (insert your TCP port number here). You have a development server for developing your own custom ClassicPress theme and you want to use your development server to backup everything from your production server.
Article published: 2022-11-17 08:47
Categories: The World of Computers, Information Technology, Internet, Networking, Scripting and Programming
If you promoted your server to a domain controller, you won't be able to change the hostname for Windows Server Domain Controller without inputting commands in the command prompt. Basically, you need to open the command prompt, add a new alternate hostname, make the domain controller your primary hostname, reboot your server, and then remove the old hostname. This is useful if the server's hostname was not changed before the server gets promoted as a domain controller. The order of commands along with the syntax is as follows:
netdom computername oldcomputername.yourlocaldomain.lan /add:newcomputername.yourlocaldomain.lan
netdom computername oldcomputername.yourlocaldomain.lan /makeprimary:newcomputername.yourlocaldomain.lan
shutdown /r /t 0
netdom computername newcomputername.yourlocaldomain.lan /remove:oldcomputername.yourlocaldomain.lan
netdom computername- The command to execute.
oldcomputername- Old hostname (example:
WIN-R61PT45).
yourlocaldomain.lan- Local domain name (example:
graysonpeddie.lan)
newcomputername- New hostname (example:
grayson-dc1)
/add- Adds a new hostname to the domain controller as an alternate hostname. For this example,
newcomputername will be added as an alternate hostname for the domain controller.
/makeprimary- Makes a hostname a primary name for the domain controller.
newcomputername will be the primary name for the domain controller and the oldcomputername will be the alternate hostname for the domain controller.
/remove- Deletes the hostname from the domain controller. In this case, the
/remove flag removes the oldcomputername from the domain controller.
/enumerate- Although not shown in the order of commands above this list of commands, parameters, and flags, this will enumerate the list of hostnames assigned to the domain controller. This flag does not require a parameter, so the colon after the enumerate flag is not needed.
shutdown /r /t 0- This command reboots the server (hence,
/r) immediately (/t 0. The /t 0 flag and parameter is a timer.
dcdiag- Not shown in the list of commands above. This command runs a diagnostic for the domain controller to make sure everything in the domain controller is working fine. There might be some errors and warnings, but if computers can login to the domain controller, it should be fine.
Because I did not know the commands myself, I must give credit to "The ICT Guy" (Twitter profile) for writing an article titled Correctly renaming a Domain Controller for a seamless easy migration. That article has been of great help to me since I am testing Windows Server 2016 Essentials edition as part of my virtual homelab setup. For example, I wanted to test the domain joining functionality in macOS and test an Active Directory integration in Nextcloud using an LDAP/AD integration app. LDAP stands for Lightweight Directory Access Protocol and is used for managing users and groups.
I hope I can be of help to Windows administrators.
Article published: 2022-09-25 01:15
Categories: The World of Computers, Information Technology
When creating Linux containers for the purpos of joining them to an Active Directory Domain Controller, make sure the checkbox after the "Unprivileged Container" is unchecked. The "unprivileged container" checkbox is after the "Hostname" edit box. Unprivileged Linux containers won't be able to join to an Active Directory. Essentially, I forgot to uncheck the "Unprivileged Container" and wasted hours of my time, but I consider time well spent when learning the hard way.
Bear in mind that privileged containers are not safe for businesses when it comes to attackers exploiting privileged Linux containers. And yes, it's all about vulnerabilities and exploits when it comes to escaping Linux containers and causing damage to the host; however, for homelab purposes, a privileged Linux container is fine for my needs. If you are concerned about the security of Linux containers, spin up virtual machines instead of Linux containers in Proxmox. Of course, depending on your security hygiene, virtual machines can be as unsafe as privileged and unprivileged Linux containers if you do not have security precautions in place. For more details, learn more about privileged and unprivileged containers.
Article published: 2022-09-22 06:27
Categories: The World of Computers, Computers, Information Technology
Instructions
- From your smartphone (not your desktop or laptop computer), open the Uber application.
- Tap Account. The Account button is located at the bottom right of your smartphone's screen.
- Tap your avatar to the right of your name.
- Tap your email address to change your email address. Skip to step 6 if you do not make use of unique email addresses for every account that you signed up for.
- Once you change your email address, tap Update. Go into your email account and look for an email from Uber. Enter the verification code that Uber gave you.
- Tap your password. You will need to verify your password first before you generate your new password from a password manager.
And you are done! Congratulations! You have successfully changed your unique email address and password! Stay safe!
Here's a link to the full article about why I changed my email address for Uber.
Article published: 2022-09-17 12:16
Categories: The World of Computers, Information Technology, Security
