You can use self-signed certificates for internal use or testing of HTTPS web services. This means you don’t need to buy a certificate from a commercial CA or generate a free Let’s Encrypt certificate. This article describes how to use the OpenSSL tool to issue a self-signed certificate in Linux, bind it to the Nginx web server and add it to the trusted certificate list on the user’s computer.
Continue reading “Creating a Self-Signed Certificate in Linux with OpenSSL”
If you specified an incorrect hostname when you installed the Proxmox VE node, you can change it.
Continue reading “How to Change the Hostname of a Proxmox VE Node”
By default, the Proxmox VE hypervisor uses commercial (enterprise) repositories to obtain updates. These updates are only available with a paid subscription. If you try to get an APT update from a commercial repo without a subscription, you will get a package source error. You must switch to pve-no-subscription repositories to receive updates without a Proxmox VE subscription.
Continue reading “Enable Free (No-Subscription) Repositories in Proxmox VE”
Bash shell scripts in Linux are used in plaintext. Obfuscation allows you to hide a Bash script’s source code by compiling it into a binary. On Linux, you can use the shc tool to compile bash scripts. This tool can convert bash script code into C language and compile it. The output will be a binary file that can be run on almost any other Linux machine.
Continue reading “Linux: Compiling a Bash Script into Binary”
To track changes to the Linux file system and report changes to apps, the inotify kernel subsystem can be used. For example, when a file or directory is created, modified, read, or deleted, inotify allows a specific action (command, script) to be executed.
Continue reading “Monitor File or Directory Changes in Linux with Systemd”
When the Linux operating system is installed on a computer, a unique machine identifier is automatically generated and saved in the /etc/machine-id file. This is similar to the Computer Security Identifier (Machine SID) in Windows.
Continue reading “How to Reset the Machine-ID of a Linux VM”
In this article, we will look at how to connect to a Microsoft SQL Server database from a Linux host (Ubuntu in this example) using an ODBC driver.
Continue reading “Connect to MS SQL Server from Linux Using ODBC Driver”
In this article, we will look at how to completely disable system logging on Linux host (including /var/log, journald, and bash command history).
Some people find that they still get popup reminders for some events even after they have deleted some events from their Outlook calendar, or even after removing the entire calendar. The problem occurs with deleted and canceled meetings in the Outlook desktop client when you have mailboxes hosted on the Exchange Server or Microsoft 365.
Continue reading “Stop Receiving Reminders from Deleted Calendar in Outlook”
An error may occur when updating the apt deb package manager cache on Linux (Ubuntu or Debian distros):
$ apt-get updateW: There is no public key available for the following key IDs: 467B942D3A79BD29
W: GPG error: https://repo.mysql.com/apt/ubuntu focal InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 467B942D3A79BD29
Continue reading “Fix: apt-get – there is no public key available”