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2024-04

Almalinux9.3_en

AlmaLinux9.3 : Anti-virus(Clamav) , Mail Server

clamav (anti-virus software] Install1.Clam AntiVirus install# dnf -y install clamav clamd clamav-update2.Clam AntiVirus  Configuration File EditMail Server Install1. Postfix1.1 InstallInstall Postfix and build an SMTP serverMail : Postfix + Clamav + clamav-milter+SpamAssassin1.Real-time scanning of e-mails①clamav-milter InstallVirus checks are performed on the mail server side using Clam AntiVirus.The mail server and Clam AntiVirus are linked using clamav-milter.
Almalinux9.3_en

AlmaLinux9.3 : WEB Server(Apache2) & Virtual Hosts

1.Apache2 Install , Virtual Host Configuration1.1 Apache2 install①httpd install# dnf -y install httpd1.3 Virtual Host SettingsAssign and configure the domain name [rocky.korodes.com] to the document root [/var/www/html/rocky.korodes.com] directory for virtual host operation2. Use of CGI Scripts①CGI availability check3. PHP installation and configuration1.PHP8 Install4. Digest authentication with Apache2Since 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
Almalinux9.3_en

AlmaLinux9.3 : FTP Server , Samba File Server

1.FTP Server1. 1 Vsftpd Install# dnf -y install vsftpd1.2 Configure VsftpdSave the unedited vsftpd.conf with .bak3. File server installation with SambaBuild a file server with access rights that requires user authentication with Samba.Installation Procedure①Create shared folders with access rights that require user authentication②Accessible group creation③Creation of users belonging to accessible groups④Configuration File Editing
Almalinux9.3_en

AlmaLinux9.3 : SSH connection with public key

SSH connection with authentication using public key cryptography Creation of public and private key pairsCreate 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_ed25519.pub will be created in /home/(user name)/.ssh/. On the way, enter the password for the key.
Almalinux9.3_en

AlmaLinux9.3 : SSH、Firewalld、NTP Server

1. SSH remote connectionSSH 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.2.How to set up a firewall (firewalld)In AlmaLinux, the firewall is set to firewalld by default and is enabled during OS installation.2.1 How to use the "firewall-cmd" command to control "firewalld"1)How to use the "firewall-cmd" command to control "firewalld"①Check firewalld operation status3.Remote connection from WindowsSetup in WindowsStart setting up a remote connection from Windows, using "Tera Term" as the terminal emulator.Start Tera Term, cancel the startup screen, and then select "New Connection" from "File" in the Tera Term menu.
Almalinux9.3_en

AlmaLinux9.3 : Various settings after installation

1. Disabling SELinuxFirst, 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 modesEnforcing : SELinux functionality is enabled and access control is enabledPermissive : SElinux will warn, but no access restrictions will be placeddisabled : Both SElinux function and access control are disabled2. System ModernizationUpdate packages as soon as possible after OS installation.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.
Almalinux9.3_en

AlmaLinux9.3 : OS Install

AlmaLinux 9.3 InstallAlmaLinux OS is a project launched by CloudLinux in the US as an alternative to CentOS. Currently, the AlmaLinux OS Foundation is the development parent organization.Following the general availability of Red Hat Enterprise Linux 9.0, AlmaLinux 9.0 was released on May 26, 2022.Like Red Hat Enterprise Linux 9, AlmaLinux 9 utilizes the same package versions as the Linux 5.14 kernel, GCC 11, Python 3.9, and RHEL9.Cockpit web management interface, enhanced kernel live patching, improved container and cloud integration, OpenSSL 3, and other security improvements.This time we will install AlmaLinux 9.3 with a minor upgrade on Nov 11, 2023.1.AlmaLinux 9.3 DownloadAlmaLinux 9.3 installation image can be downloaded from the following sitehttps://almalinux.org
Ubuntu24.04_en

Ubuntu Server24.04 : SSH , Firewall(UFW)

1. SSH Service Security SettingsThe SSH service allows the root user to log in by default, and since the root user already knows the user name and can log in to the server with administrative privileges once the password is known, we will deny this setting.1.1 Creating a General UserIf you have created a general user when installing Ubuntu 24.04, this procedure is not necessary.If you have already created a user at the time of OS installation, this procedure is not necessary. If you have already created a user during OS installation, this procedure is not necessary.If you have already created a user during OS installation, this procedure is not necessary. The "-m" option creates a home directory and the "-p" option specifies the password.For example, to set "ubuntuuser" as the user account name and "123456" as the password, execute as follows
Ubuntu24.04_en

Ubuntu Server24.04 : Initial settings after OS installation

1. Set root password and use SU commandIn the default configuration of Ubuntu, the root user is unavailable because no password has been set.By setting a password for the root user, transitions using the traditional [su] command will be possible.3. Make locate command availableThe find command is often used to search for specific files throughout the Linux system, but find is somewhat confusing in terms of specifying options.The locate command can extract all files with a specified filename.4. vim editor settingsUbuntu has vim installed by default4.1 Change vim settingsThere may be cases where you do not want to allow vim settings for all users. In such cases, a ".vimrc" file can be created in each user's home directory to change the vim environment for each user.In this case, we will create a ".vimrc" file in the root user's home directory "/root/" and apply it to all users.
FreeBSD13.3_en

FreeBSD13.3 : WEB Server(Apache2) , MySQL8

1. Apache21.1 Install# cd /usr/ports/www/apache24# make configThere are many options, but we will proceed with the defaults2. MySQL InstallInstall MySQL before installing PHP# pkg install -y mysql80-client mysql80-server3. apache24 - PHP 8.03.1 PHP Install# cd /usr/ports/lang/php83# make config
FreeBSD13.3_en

FreeBSD13.3 : Initial setup (Vim , SSH , firewall, NTP server)

1. Vim InstallInstall Vim, which you are familiar with as an editor, as follows# pkg install -y vim2. SSH Connection Security Measures2.1 SSH port changed, root user login disabled3. Firewall SettingsFreeBSD has the following firewalls・pf・ipfw・ipfIn this case, we will use ipfw to configure the firewall4. NTP Server Settings4.1 Rewrite the referenced NTP server in /etc/ntp.conf. Add an appropriate server in Japan.
FreeBSD13.3_en

FreeBSD13.3 : Initial setting (Update binaries, Packages and Ports Collection)

After installing FreeBSD, we will start building the server, but it is difficult to work on the console screen, so we will change the SSH connection settings for now in order to operate the server from Windows using TeraTerm or other software.Enter the following command on the FreeBSD console screen# vi /etc/ssh/sshd_configLine 61.#PasswordAuthentication no → PasswordAuthentication yes Make the changes and reflect the settings with the following command# service sshd restartNow you can connect via SSH from TeraTerm on Windows (see the default settings for other operating systems for settings in TeraTerm).
OracleLinux9.3_en

OracleLinux9.3 : System Backup and Restore

1.Website data backup1-1.Backup under /var/www/html①Create backup script file2.MySQL database backup①Create backup script file# cd /var/www/system# vi db_my_backup.sh3.Restore backup files under html① Store HTML backup files in "/ (root)" directory# cd /var/www/backup/html_bak# cp html_back_20220610.tar.gz / ←Specify the backup file with the latest date4.Restore Mysql backup file①Save the database backup file to any directory and(In the example, the directory is "/var/www/backup/db_bak".)Extracting data# cd /var/www/backup/db_bak
OracleLinux9.3_en

OracleLinux9.3 : MySQL8 , WordPress Install

Mysql8 Install# dnf -y install mysql-serverCreate a new charset.cnf with the following contentsWordPress Install1. Create database for Word PressAs an example, assume database [wp_db] database user [wp_user] password [?W123456]
Almalinux9.3_en

AlmaLinux9.3 : Logwatch , Disk Usage Check Script

1. Logwatch①Install# dnf install logwatch②Edit configuration file2.Introduce disk usage check script2.1 Script Creation# cd /var/www/system# vi disk_capacity_check.sh