This article is intended for Hostwinds clients who have chosen to install CentOS 7 to begin configuring and customizing server using the command line interface. We highly recommend taking a snapshot backup before making any modifications in case you need to restore it at any time. Below are some basic configurations you can view and configure to fit your needs. This article is meant to offer our Unmanaged clients with some basic commands and information to help you get started with a clean install of CentOS 7 on your Instance.
Any commands that are preceded with a # is suggeseted to be using root user access. Commands preceded with a $ indicate that a regular user can perform these tasks.
Basic System Configuration
Date and Time
Displaying Current Date and Time using one of the following commands
Changing Local Time
$ timedatectl list-timezones
# timedatectl set-timezone [time_zone]
Change [time_zone] to the time zone you prefer to use for your local time from an option on the list-timezones results
List all available locales
$ localectl list-locales
Show current locale setting
# localectl status
Set or change system locale
# localectl set-locale LANG=[locale]
Replace [locale] above with the locale setting of your choice
Manage Software using Yum
List all enabled repositories
$ yum repolist
Search for a package using yum
$ yum search [string]
Replace [string] above with what you are searching for
Install a package
# yum install [package_name]
Replace [package_name] above with the package name
Update all packages and their dependencies
# yum update
Enable a service on boot
# systemctl enable [service]
Disable a service on boot
# systemctl disable [service]
Replace [service] with the name of the service.
Install ConfigServer Security & Firewall (CSF) or Firewalld
If you decide to use CSF instead of firewalld, here are the installation instructions:
# cd /usr/src
# rm -fv csf.tgz
# wget https://download.configserver.com/csf.tgz
# tar -xzf csf.tgz
# cd csf
# sh install.sh
Enable csf and lfd using your favorite text editor so that it can be started and taken out of testing. Just open the /etc/csf/csf.conf file and replace TESTING = “1” with TESTING = “0” and save this file.
Next, start csf:
# systemctl start csf
# systemctl start lfd
Now, enable csf and lfd to begin on startup:
# systemctl enable csf
# systemctl enable lfd
You can then configure csf and lfd by reading the documentation and configuration files in /etc/csf/csf.conf and /etc/csf/readme.txt directly or through the csf User Interface.
If you prefer to use firewalld with SELinux and not csf, the instructions are below:
# yum install firewalld
Start Firewalld and begin on system startup
# systemctl enable firewalld
To set SELinux to permanently enforcing so that SELinux polices are enforced, modify the /etc/selinux/config configuration file using your favorite text editor and set this to enforcing as seen below and save these changes.
Generate SSH Keys
If you have not already generated a key when creating your instance, of if you would like to add another key pair, you can do so with the help of the guide to Create a Strong SSH Key in Linux
Manage User Accounts
Create a new user
# useradd [options] [user_name]
Use useradd –help to see the options to replace in [options] above and also replace [user_name] with the username you would like to create.
Assign a password to a user
# passwd [user_name]
Replace [user_name] above with the username.
Add a User to a Group
# usermod -a -G [group_name] [user_name]
Replace [group_name] with the group name you want to assign the user to and the [user_name] with the desired user name you would like to assign to a group.
If you are having any trouble with our Managed Services, or have any questions, please let us know so that we can help you.