2023-10

SSH connection with authentication using public key cryptographyCreation 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_eed25519.pub will be created in /home/(user name)/.ssh/. On the way, enter the password for the key.

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

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

Snort3 InstallSnort is an open source network intrusion detection system capable of performing real-time traffic analysis and packet logging on IP networks.It can perform "protocol analysis," "content search," and "matching," and can be used to detect a variety of attacks, including "buffer overflows," "stealth port scans," "CGI attacks," "SMB probes," "OS fingerprinting attempts," "semantic URL attacks," and "server message block probes.MiracleLinux8 does not have a Snort3 repository, so build, compile and install Snort3 from source code1. Advance preparation①Install required build tools and libraries

1.Website data backup1-1.Backup under /var/www/html①Create backup script file# cd /var/www/system# vi backup_html.sh2.MySQL database backup①Create backup script file# cd /var/www/system# vi db_my_backup.sh3.Restore backup files under html①Store HTML backup files in "/ (root)" directory4.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

Snort3 InstallSnort is an open source network intrusion detection system capable of performing real-time traffic analysis and packet logging on IP networks.It can perform "protocol analysis," "content search," and "matching," and can be used to detect a variety of attacks, including "buffer overflows," "stealth port scans," "CGI attacks," "SMB probes," "OS fingerprinting attempts," "semantic URL attacks," and "server message block probes.MiracleLinux8 does not have a Snort3 repository, so build, compile and install Snort3 from source code1. Advance preparation①Install required build tools and libraries

chkrootkit Install①chkrootkit Download and installation# cd /usr/local/src# wget https://launchpad.net/chkrootkit/main/0.55/+download/chkrootkit-0.55.tar.gz# tar xvf chkrootkit-0.55.tar.gz➁Create /root/bin directory and move chkrootkit command to that dirLogwatch①Install# dnf install logwatch②Edit configuration file# cat /usr/share/logwatch/default.conf/logwatch.conf >> /etc/logwatch/conf/logwatch.conf# vi /etc/logwatch/conf/logwatch.confPer Line 45Set "MailTo = root" as a comment and set the email address you want to receive notifications to the line below it.#MailTo = rootMailTo = [Mail address]Per Line 79Set the level of detail for log notifications#Detail = LowDetail = High③Output Logwatch reports# logwatch --output stdout

2. Vsftpd over SSL/TLSLS2.1 Create self-signed certificatesThis work is not required if you are using a trusted, legitimate certificate such as Let's Encrypt.3. 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

SSH public key cipher setting1.Create a key pairCreate a public/private key pair for a user connecting to a Linux server using OpenSSH.Use ssh-keygen to create the key pair.The creation of a public/private key pair must be done as a user with remote login 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.

MiracleLinuxMIRACLE LINUX is a Japanese Linux distribution provided by Cybertrust Corporation.Development was started by Miracle Linux (now Cybertrust), a company established by Oracle Japan and NEC in June 2000 to ensure stable operation of the Oracle Database for business to enterprise use.It has been built as a RHEL base since Version 2.0 released in May 2001, and as a complete RHEL clone since Version 6.0 released in January 2012.The latest version is 8.8, released on October 05, 2023, but can be installed just like 8.4.MIRACLE LINUX, a well-known domestic RHEL clone, was initially a commercial OS with a paid license, but following the demise of CnetOS8, it was announced that it would be offered free of charge starting with the latest 8.4 version. Therefore, this OS is currently in the limelight as a candidate for migration from CentOS8.

1. Disable 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. If you build a server while browsing a website and it does not work as expected, it may be due to the fact that selinux is enabled. Therefore, do not forget to disable it after installation.You can disable it by doing the following

1.Setting up a remote connection via SSHSSH 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 SSH service configuration file changesModify the configuration file to change the SSH service settings.The SSH service configuration file is "/etc/ssh/sshd_config".

1.Apache2 Install , Virtual Host Configuration1.1 Apache2 install2. Use of CGI Scripts①CGI availability check3. PHP installation and configuration4. 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 information, so there is almost no risk of information leakage.

1.SSL Certificate Acquisition ( Let's Encrypt )Install the latest open ssl# dnf install openssl-devel1.1 advance preparation1.Package management system Snappy installationSince 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 httpsInstall the following# dnf -y install mod_ssl3. SSL/TLS (Let's Encrypt) settings on the mail server3.1 Obtaining a certificate for the mail serverObtain 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.

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]