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2024-04

Almalinux9.3_en

AlmaLinux9.3 ; Suricata , Tripwire , Chkrootkit

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 Tripwire 1.Installation # dnf install -y tripwire Chkrootkit ①Download and install chkrootkit
2024.04.17
Almalinux9.3_en
Rocky Linux9.3_en

Rocky Linux9.3 ; Logwatch , Disk Usage Check Script

1. Logwatch ①Install # dnf install logwatch ②Edit configuration file 2.Introduce disk usage check script 2.1 Script Creation # cd /var/www/system # vi disk_capacity_check.sh
2024.04.13
Rocky Linux9.3_en
Rocky Linux9.3_en

Rocky Linux9.3 ; SSL Certificate Acquisition( Let's Encrypt ) , Apache SSL , Mail SSL/TLS

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.
2024.04.12
Rocky Linux9.3_en
Rocky Linux9.3_en

Rocky Linux9.3 ; SSH connection with public key

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_ed25519.pub will be created in /home/(user name)/.ssh/. On the way, enter the password for the key.
2024.04.11
Rocky Linux9.3_en
Rocky Linux9.3_en

Rocky Linux9.3 ; Various settings after installation

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.
2024.04.11
Rocky Linux9.3_en
Ubuntu24.04_en

Ubuntu Server24.04 ; OS Install

Ubuntu Server 24.04 Download Installation Image The installation media for Ubuntu Server can be downloaded from the official site on the Internet. As long as you have a fast connection, you can download the OS itself in about 2 to 3 minutes. You will need to create an installation CD/DVD from the downloaded iso file. (approx. 2.7G) The iso file itself can be used for installation on a virtual machine using Vmware or other software. The iso file can be downloaded from the "Official Ubuntu Download Site". Ubuntu 24.04 (released on April 25, 2024) is supported until April 2029, so it is safer to install the LTS version of Ubuntu 24.04 in the production environment.
2024.04.30
Ubuntu24.04_en
Almalinux9.3_en

AlmaLinux9.3 ; OS Install

AlmaLinux 9.3 Install AlmaLinux 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 Download AlmaLinux 9.3 installation image can be downloaded from the following site https://almalinux.org
2024.04.15
Almalinux9.3_en
Rocky Linux9.3_en

Rocky Linux9.3 ; OS Install

Rocky Linux9.3 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. This time we will install Rocky Linux 9.3, released NOVEMBER 20, 2023.
2024.04.10
Rocky Linux9.3_en
Ubuntu24.04_en

Ubuntu Server24.04 ; Initial settings after OS installation

1. Set root password and use SU command In 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 available The 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 settings Ubuntu has vim installed by default 4.1 Change vim settings There 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.
2024.04.30
Ubuntu24.04_en
OracleLinux9.3_en

OracleLinux9.3 ; OS Install

OracleLinux9.3 Oracle Linux provides a 100% application binary compatible alternative to Red Hat Enterprise Linux and  CentOS Linux for both hybrid and multi-cloud environments. Since 2006, Oracle Linux has been completely free to download and use. Source code, binaries and updates are provided free of charge. It is freely redistributable. Free for use in production environments. This time, we will proceed with the latest Oracle Linux 9.3.(November 15, 2023 Release) １．Oracle Linux9.3 Download Oracle Linux 9.3 installation image (OracleLinux-R9-U3-x86_64-dvd.iso ) can be downloaded from the following site https://www.oracle.com/linux/
2024.04.19
OracleLinux9.3_en
Ubuntu24.04_en

Ubuntu Server24.04 ; SSH , Firewall(UFW)

1. SSH Service Security Settings The 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 User If 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
2024.04.30
Ubuntu24.04_en
Ubuntu24.04_en

Ubuntu Server24.04 ; SSH connection with authentication using public key cryptography

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_ed25519.pub will be created in /home/(user name)/.ssh/. On the way, enter the password for the key.
2024.04.30
Ubuntu24.04_en
fedora40_en

Fedora40 ; OS Install

Fedora40 ; Download(Released on April 24, 2024) Fedora40 can be downloaded from the following mirror https://ftp.riken.jp/Linux/fedora/releases/40/Server/x86_64/iso/ The file to download is the "Fedora-Server-dvd-x86_64-40-1.14.iso" image Create an installation disk from the downloaded "Fedora-Server-dvd-x86_64-40-1.14.iso" image on a USB disk and install it on the actual device. Fedora40 ; Install ①Change to boot from USB disk on the BIOS change screen of the PC and boot the PC. Select "Install Fedoara 40" at the top and press Enter
2024.04.26
fedora40_en
fedora40_en

Fedora40 ; Various settings after installation

1. SELinux Disable First, disable selinux. selinux is a feature that improves auditing and security in Linux, but when enabled, it can limit the behavior of services and the configuration considerably. Therefore, it is basically invalidated in many cases. You can disable it by doing the following。 2. System modernization & Services suspended due to security measures 2.1 System modernization 3.Network Settings 3.1 Set host name To set the hostname to "Lepard 4.Install NTP server and set up time synchronization service 4.1 Chrony Install 5.Set server time zone Set time zone to Japan (Tokyo) 6.Install and configure vim editor ①Installing the vim package
2024.04.26
fedora40_en
fedora40_en

Fedora40 ; SSH 、Firewalld

1.Remote connection by SSH SSH is a service for connecting remotely to a server, basically running immediately after OS installation, but the default settings are somewhat insecure. Configure the default settings to increase the security of ssh connections. 1.1 SSH service configuration file changes The SSH service configuration file is "/etc/ssh/sshd_config". Open the configuration file in a vi editor.
2024.04.26
fedora40_en
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