Rocky Linux9.1_en

1.Disabling SELinux First, disable selinux. selinux is a feature that improves auditing and security in Linux, but when enabled, it places considerable restrictions on the behavior of services and on what can be configured. Therefore, it is basically disabled in many cases. SELinux operating modes Enforcing : SELinux functionality is enabled and access control is enabled Permissive : SElinux will warn, but no access restrictions will be placed disabled : Both SElinux function and access control are disabled 2.System Modernization Package updates are performed as soon as possible immediately after OS installation. However, when a dnf update is performed, a kernel update is also performed at the same time. A kernel update may require rebooting the system or stopping services, or worse, a kernel panic may occur and the system may not boot. It is wiser to exclude the kernel from the update. The kernel can be excluded from updates by running dnf -y update with "--exclude=kernel*" after it.

SSH connection with authentication using public key cryptography Creation of public and private key pairs Create a public/private key pair for a user connecting to the Linux server using OpenSSH. Use ssh-keygen to create key pairs. Creation of public/private key pairs is performed with remote login user privileges。 If you do not specify the destination and file name, id_ed25519 and id_eed25519.pub will be created in /home/(user name)/.ssh/. On the way, enter the password for the key.

1. Logwatch ①Install # dnf install logwatch ②Edit configuration file 2. DiCE Whenever the global IP changes, which happens when the network is disconnected or the router is disconnected and rebooted, the dynamic DNS must be accessed to inform the user that the global IP has changed. DiCE does this automatically! 3.Introduce disk usage check script 3.1 Script Creation # cd /var/www/system # vi disk_capacity_check.sh

Rocky Linux9.0 The Rocky Release Engineering team announced the latest version of Rocky Linux 9.0 on July 14, 2022. Rocky Linux is a Linux distribution compatible with Red Hat Enterprise Linux; Rocky Linux 9 is a compatible release with RHEL 9 released in May and will be supported until the end of May 2032. In security, password-based root user authentication via SSH is now disabled by default. SSH keys can be used to access remote systems instead of root passwords. OpenSSL supports version 3.0.1, enhanced support for HTTPS clients, and a new FIPS module.

1.Apache2 Install , Virtual Host Configuration 1.1 Apache2 install ①httpd install # dnf -y install httpd 1.3 Virtual Host Settings Assign and configure the domain name [rocky.korodes.com] to the document root [/var/www/html/rocky.korodes.com] directory for virtual host operation 2. Use of CGI Scripts ①CGI availability check 3. PHP installation and configuration 1.PHP8 Install 4. Digest authentication with Apache2 Since Basic Authentication, a well-known authentication authorization method for http, sends authentication information in plain text, there is a risk of ID and password leakage if the packet is intercepted. On the other hand, Digest Authentication encrypts and transmits authentication informa

clamav (anti-virus software] Install 1.Clam AntiVirus install # dnf -y install clamav clamd clamav-update 2.Clam AntiVirus  Configuration File Edit Mail Server Install 1. Postfix 1.1 Install Install Postfix and build an SMTP server

1.Website data backup 1-1.Backup under /var/www/html ①Create backup script file # cd /var/www/system # vi backup_html.sh 2.MySQL database backup ①Create backup script file # cd /var/www/system # vi db_my_backup.sh 3.Restore backup files under html ①Store HTML backup files in "/ (root)" directory 4.Restore Mysql backup file ①Save the database backup file to any directory and （In the example, the directory is "/var/www/backup/db_bak".）Extracting data

Suricata SURICATA IDS/IPS is an open source IDS that monitors communications on the network and detects suspicious traffic. The basic mechanism is signature-based, so it can detect predefined unauthorized communications. Suricata is also characterized by its ability to provide protection as well as detection. 1.advance preparation ①Activate the EPEL Repository # dnf -y install epel-release Tripwire 1.Download and installation # cd /usr/local/src # wget https://rpmfind.net/linux/epel/9/Everything/x86_64/Packages/t/tripwire-2.4.3.7-13.el9.x86_64.rpm # rpm -Uvh tripwire-2.4.3.7-13.el9.x86_64.rpm Chkrootkit ①Download and install chkrootkit # cd /usr/local/src # wget https://launchpad.net/chkrootkit/main/0.55/+download/chkrootkit-0.55.tar.gz # tar xvf chkrootkit-0.55.tar.gz

Mysql8 Install ＃ dnf -y install mysql-server charset.cnf   Create a new one with the following contents WordPress Install 1. Create database for Word Press As an example, assume database [wp_db] database user [wp_user] password [?W123456]

1.Obtain an SSL certificate ( Let's Encrypt ) Install the latest open ssl # dnf install openssl-devel 1.1 advance preparation 1.Package management system Snappy installed Since the SSL certificate issuing tool "certbot" of Let's Encrypt is recommended to be installed using "snap" after 2021, install Snapd first.(Can also be installed the traditional way with dnf or yum) 2. Converting Apache to https Install the following just in case # dnf -y install mod_ssl 3. SSL/TLS (Let's Encrypt) settings on the mail server 3.1 Obtaining a certificate for the mail server Obtain a certificate for the mail server, but it cannot be obtained in the same way as above, so the following with the "--standalone" option fails.

1.FTP Server 1. 1 Vsftpd Install # dnf -y install vsftpd 1.2 Configure Vsftpd Save the unedited vsftpd.conf with .bak 3. File server installation with Samba Build a file server with access rights that requires user authentication with Samba. Installation Procedure ①Create shared folders with access rights that require user authentication ②Accessible group creation ③Creation of users belonging to accessible groups ④Configuration File Editing

1.Remote connection via SSH SSH is a service for connecting remotely to a server and is basically running immediately after the OS is installed, but the default settings are somewhat insecure. Here we will configure the default settings to increase the security of ssh connections. 1.1 Edit SSH service configuration file Modify the configuration file to change the SSH service settings. The SSH service configuration file is "/etc/ssh/sshd_config". 2.Firewall (firewalld) settings The firewall is set to firewalld as default and is enabled during OS installation. 4.NTP Server Build an NTP server to synchronize the server time with Japan Standard Time