Linux Server Hardening Security Tips 2. Craft. Securing your Linux server is important to protect your data, intellectual property, and time, from the hands of crackers hackers. Screenshot-from-2017-01-05-174917.png' alt='Install Openvz On Centos 7 Change' title='Install Openvz On Centos 7 Change' />Operatingsystemlevel virtualization, also known as containerization, refers to an operating system feature in which the kernel allows the existence of multiple. Hp Color Laserjet Cp5525 Printer Driver. Sometimes the situation might come up where a device that was working flawlessly before will stop doing so, even if you try everything replugging it, reinstalling. The system administrator is responsible for security of the Linux box. In this first part of a Linux server security series, I will provide 4. Linux system. Linux Server Hardening Checklist and Tips. The following instructions assume that you are using Cent. Many folks who need web hosting these days want the simplest method for managing servers. To many, it is expected that graphicaluserinterfaces GUIs are provided. Migrating a DHCP from Server 2012 R2 to Server 2016 involves only two commands. The first command is to export the DHCP data and is run on Server 2012 R2. The second. A webbased interface for system administration for Unix. Setup user accounts, DNS, file sharing and the program is freeware. OSRHEL or UbuntuDebian based Linux distribution. Encrypt Data Communication. All data transmitted over a network is open to monitoring. Adobe Flex Pros And Cons more. Encrypt transmitted data whenever possible with password or using keys certificates. Use scp, ssh, rsync, or sftp for file transfer. You can also mount remote server file system or your own home directory using special sshfs and fuse tools. Gnu. PG allows to encrypt and sign your data and communication, features a versatile key management system as well as access modules for all kind of public key directories. Install Openvz On Centos 7 Change' title='Install Openvz On Centos 7 Change' />Open. VPN is a cost effective, lightweight SSL VPN. Another option is to try out tinc that uses tunneling and encryption to create a secure private network between hosts on the Internet or private insecure LAN. Lighttpd SSL Secure Server Layer Https Configuration And Installation. Apache SSL Secure Server Layer Https modssl Configuration And Installation. How to configure Nginx with free Lets Encrypt SSL certificate on Debian or Ubuntu Linux2 Avoid Using FTP, Telnet, And Rlogin Rsh Services. Under most network configurations, user names, passwords, FTP telnet rsh commands and transferred files can be captured by anyone on the same network using a packet sniffer. The common solution to this problem is to use either Open. SSH, SFTP, or FTPS FTP over SSL, which adds SSL or TLS encryption to FTP. Type the following yum command to delete NIS, rsh and other outdated service yum erase xinetd ypserv tftp server telnet server rsh server. If you are using a DebianUbuntu Linux based server, try apt get commandapt command to remove insecure services sudo apt get purge remove xinetd nis yp tools tftpd atftpd tftpd hpa telnetd rsh server rsh redone server3 Minimize Software to Minimize Vulnerability. Do you really need all sort of web services installed Avoid installing unnecessary software to avoid vulnerabilities in software. Use the RPM package manager such as yum or apt get andor dpkg to review all installed set of software packages on a system. Delete all unwanted packages. Name yum remove package. Name. OR dpkg list dpkg info package. Name apt get remove package. Name4 One Network Service Per System or VM Instance. Run different network services on separate servers or VM instance. This limits the number of other services that can be compromised. For example, if an attacker able to successfully exploit a software such as Apache flow, he or she will get an access to entire server including other services such as My. SQLMaria. DBPGSql, e mail server and so on. See how to install Virtualization software for more info 5 Keep Linux Kernel and Software Up to Date. Applying security patches is an important part of maintaining Linux server. Linux provides all necessary tools to keep your system updated, and also allows for easy upgrades between versions. All security update should be reviewed and applied as soon as possible. Again, use the RPM package manager such as yum andor apt get andor dpkg to apply all security updates. OR apt get update apt get upgrade. You can configure Red hat Cent. OS Fedora Linux to send yum package update notification via email. Another option is to apply all security updates via a cron job. Under Debian Ubuntu Linux you can use apticron to send security notifications. It is also possible to configure unattended upgrades for your DebianUbuntu Linux server using apt get commandapt command sudo apt get install unattended upgrades apt listchanges bsd mailx6 Use Linux Security Extensions. Linux comes with various security patches which can be used to guard against misconfigured or compromised programs. If possible use SELinux and other Linux security extensions to enforce limitations on network and other programs. For example, SELinux provides a variety of security policies for Linux kernel. SELinux. I strongly recommend using SELinux which provides a flexible Mandatory Access Control MAC. Under standard Linux Discretionary Access Control DAC, an application or process running as a user UID or SUID has the users permissions to objects such as files, sockets, and other processes. Running a MAC kernel protects the system from malicious or flawed applications that can damage or destroy the system. See the official Redhat documentation which explains SELinux configuration. User Accounts and Strong Password Policy. Use the useradd usermod commands to create and maintain user accounts. Make sure you have a good and strong password policy. For example, a good password includes at least 8 characters long and mixture of alphabets, number, special character, upper lower alphabets etc. Most important pick a password you can remember. Use tools such as John the ripper to find out weak users passwords on your server. Configure pamcracklib. Password Aging. The chage command changes the number of days between password changes and the date of the last password change. This information is used by the system to determine when a user must change hisher password. The etclogin. defs file defines the site specific configuration for the shadow password suite including password aging configuration. To disable password aging, enter chage M 9. Name. To get password expiration information, enter chage l user. Name. Finally, you can also edit the etcshadow file in the following fields user. Name password lastpasswdchanged Minimumdays Maximumdays Warn Inactive Expire Where,Minimumdays The minimum number of days required between password changes i. Maximumdays The maximum number of days the password is valid after that user is forced to change hisher password. Warn The number of days before password is to expire that user is warned that hisher password must be changed. Expire Days since Jan 1, 1. I recommend chage command instead of editing the etcshadow file by hand chage M 6. W 7 user. Name. Recommend readings 1. Restricting Use of Previous Passwords. You can prevent all users from using or reuse same old passwords under Linux. The pamunix module parameter remember can be used to configure the number of previous passwords that cannot be reused. Locking User Accounts After Login Failures. Under Linux you can use the faillog command to display faillog records or to set login failure limits. It also can be used for maintains failure counters and limits. To see failed login attempts, enter faillog. To unlock an account after login failures, run faillog r u user. Name Note you can use passwd command to lock and unlock accounts lock accountpasswd l user. Name unlocak accountpasswd u user. Name1. 2 How Do I Verify No Accounts Have Empty Passwords Type the following command awk F 2 print etcshadow. Lock all empty password accounts passwd l account. Name1. 3 Make Sure No Non Root Accounts Have UID Set To 0. Only root account have UID 0 with full permissions to access the system.