Rocky Linux Administration Memo: Essential Commands and Configuration Notes

How to Change the SSH Connection Port

For example, if you want to change the SSH connection port from 22 to 50022, in /etc/ssh/sshd_config, change the following

#Port 22

as shown below and

Port 50022

restart the service.

# systemctl restart sshd

# semanage port -a -t ssh_port_t -p tcp 50022

# firewall-cmd --permanent --zone=public --add-port=50022/tcp
# firewall-cmd --reload

If you want to use Wi-Fi

If you want to use Wi-Fi, install the NetworkManager-wifi package.

# dnf install NetworkManager-wifi

How to set password complexity

Edit the following file.

/etc/security/pwquality.conf

The contents of the file are as follows.

# The check is disabled if the value is 0.
# maxclassrepeat = 0
#
# Whether to check for the words from the passwd entry GECOS string of the user.
# The check is enabled if the value is not 0.
# gecoscheck = 0
#
# Whether to check for the words from the cracklib dictionary.
# The check is enabled if the value is not 0.
# dictcheck = 1
#
# Whether to check if it contains the user name in some form.
# The check is enabled if the value is not 0.
# usercheck = 1
#
# Length of substrings from the username to check for in the password
# The check is enabled if the value is greater than 0 and usercheck is enabled.
# usersubstr = 0
#
# Whether the check is enforced by the PAM module and possibly other
# applications.
# The new password is rejected if it fails the check and the value is not 0.
# enforcing = 1
#
# Path to the cracklib dictionaries. Default is to use the cracklib default.
# dictpath =
#
# Prompt user at most N times before returning with error. The default is 1.
# retry = 3
#
# Enforces pwquality checks on the root user password.
# Enabled if the option is present.
# enforce_for_root
#
# Skip testing the password quality for users that are not present in the
# /etc/passwd file.
# Enabled if the option is present.
# local_users_only

How to install in text mode

• When the following screen appears, enter e.

• Add inst.text.
• Press Ctrl + X or F10.

• Enter 2.

• The installation will proceed in text mode.