Several Useful Linux Tools

The following tools may have been installed in your Linux because some are basic tools. But, if we installed any Linux distribution from the Docker registry which is shipped with only minimal programs, these following tools may be not available by default.

net-tools
This tool provides tools for network-related tasks such as ifconfig.

software-properties-common
If you want to enable add-apt-repository command, this tool is required.

nano
This text editor is usually already available.

ca-certificates
A deb package that contains certificates provided by the Certificate Authorities. It also contains an updater tool that can be used as a cronjob if needed.

gnupg2
GNU Privacy Guard is GNU's tool that can be used to encrypt data and to create digital signatures. GnuPG is a complete replacement for PGP. It includes an advanced key management facility and is compliant with the proposed OpenPGP Internet standard.

openssh-client
Tools for generating authentication keys and others such as ssh-keygen

curl & wget
It can create HTTP-request.

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Installing APCu in PHP 7

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Configuring Swap Memory on Ubuntu Using Ansible

If we maintain a Linux machine with a low memory capacity while we are required to run an application with high memory consumption, enabling swap memory is an option. Ansible can be utilized as a helper tool to automate the creation of swap memory. A swap file can be allocated in the available storage of the machine. The swap file then can be assigned as a swap memory. Firstly, we should prepare the inventory file. The following snippet is an example, you must provide your own configuration. [server] 192.168.1.2 [server:vars] ansible_user=root ansible_ssh_private_key_file=~/.ssh/id_rsa Secondly, we need to prepare the task file that contains not only the tasks but also some variables and connection information. For instance, we set /swapfile as the name of our swap file. We also set the swap memory size to 2GB and the swappiness level to 60. - hosts: server become: true vars: swap_vars: size: 2G swappiness: 60 For simplicity, we only check the exi

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