Shutdown in Linux and Solaris CLI

To shut a system down, one of two commands are typically used: shutdown or init. Both commands perform a clean shutdown of the system. Both start processes that write all file system changes to disk and terminate all system services, processes, and the OS. The following table describes the various shutdown commands used in Linux / Solaris OS and provides … Read more

Server Memory(DIMM) Population rules for HPE Gen10 Servers

HPE SmartMemory DIMMs and HPE NVDIMM-Ns may be populated in many permutations that are allowed but may not provide optimal performance. The system ROM reports a message during the power on self-test if the population is not supported or is not balanced. Table 2 shows the population guidelines for HPE SmartMemory DIMMs in HPE Gen10 … Read more

Create Custom or Disable DST(daylight-saving time) in Oracle Solaris 10

A few weeks ago, it is announced (by The Energy and Natural Resources Ministry of Iran) that DST will be permanent and GMT+3:30(IRST) will be used forever in the country. From 2023, Iran will not set their clocks forward for Daylight Saving Time (DST) but remain on standard time permanently. Based on following manual, we … Read more

Create a Custom or Disable DST(daylight-saving time) in RHEL/CentOS Linux

A few weeks ago, it is announced (by The Energy and Natural Resources Ministry of Iran) that DST will be permanent and GMT+3:30(IRST) will be used forever in the country. From 2023, Iran will not set their clocks forward for Daylight Saving Time (DST) but remain on standard time permanently. Based on following manual, we … Read more

Install VNC Server to connect with GUI in RHEL/CentOS Linux

Virtual network computing (VNC) is a type of remote-control software that makes it possible to control another computer over a network connection. Keystrokes and mouse clicks are transmitted from one computer to another. ### Install VNC Server [root@testos ~]# yum install -y tigervnc-server ### If firewalld is running, allow VNC service [root@testos ~]# firewall-cmd –add-service=vnc-server … Read more

Package Management in RHEL/CentOS 7,8 Linux

RPM is a command-line utility for managing packages on Unix/Linux systems. It allows you to install, query, update, verify and remove RPM packages.It is the default package manager for Red Hat based systems and only works with the .rpm format. You can install such packages using the rpm or the yum command.The package management tool … Read more

Working with Services in RHEL/Centos 7

### It’s possible to check all services like follow: # the list of all services [root@testos]# systemctl list-unit-files -t service UNIT FILE STATE abrt-ccpp.service enabled abrt-oops.service enabled abrt-pstoreoops.service disabled abrt-vmcore.service enabled abrt-xorg.service enabled abrtd.service enabled arp-ethers.service disabled atd.service enabled auditd.service disabled auth-rpcgss-module.service static autofs.service disabled autovt@.service enabled blk-availability.service disabled brandbot.service static certmonger.service enabled chrony-dnssrv@.service static … Read more

Enable SSL/TLS for vsftpd to use Secure FTP(SFTP) connections in RHEL/Centos

### Create self-signed certificate. [root@testos ~]# cd /etc/pki/tls/certs[root@testos certs]# openssl req -x509 -nodes -newkey rsa:2048 -keyout vsftpd.pem -out vsftpd.pem -days 365Generating a 2048 bit RSA private key……++++++…….++++++ writing new private key to ‘/etc/pki/tls/certs/vsftpd.pem’ You are about to be asked to enter information that will be incorporatedinto your certificate request.What you are about to enter is … Read more

Install and configure vsftpd to configure FTP Server in RHEL/Centos

### Configure Vsftpd [root@testos ~]# yum -y install vsftpd ### Edit/Update vsftpd Configuration file [root@testos ~]# vi /etc/vsftpd/vsftpd.conf # line 12: no anonymous anonymous_enable=NO # line 82,83: uncomment ( allow ascii mode ) ascii_upload_enable=YES ascii_download_enable=YES # line 100, 101: uncomment ( enable chroot ) chroot_local_user=YES chroot_list_enable=YES # line 103: uncomment ( specify chroot list ) … Read more