HPL benchmark solves a randomly generated dense linear system of equations in double floating-point precision (IEEE 64-bit) arithmetic...
Download Intel Parallel Studio XE 2020 In this example Intel Parallel Studio XE 2020 Cluster Edition tar xf...
The STREAM benchmark is a simple synthetic benchmark program that measures sustainable memory bandwidth (in MB/s) and the corresponding...
Follow the steps below to compile and run HPC Challenge Benchmark on CentOS 8. Download and unarchive source code: yum...
Default vlan 1 does not behave as vlan 1 on mellanox. Best practice - do not use VLAN 1. But sometimes you need to use VLAN 1. Example...
1. Configure iSCSI target server and initiator clients 1.1. Servers Install 3 servers with following IP addresses. Storage server will...
"rpmbuild -tb" is not enough on CentOS 8.1 to build SLURM 18.x and 19.x rpms. yum install epel-release yum --enablerepo=PowerTools...
Starting with CentOS 7.4 package pcp-zeroconf is available. It will install and enable pmcd and pmlogger. yum -y install pcp-zeroconf...
Still there is no update for mutter package to fix this issue. Solution Example on CentOS 7.5 minimal: yum -y group install "Development...
This post shows 2 options: Self Signed Certificate without CA Self Signed Certificate with CA (Certificate Authority) Also it shows how...
AWX is the upstream project from which the Red Hat Ansible Tower offering is ultimately derived. Read more: AWX project FAQ Install...
This issue happens on some hardware nodes. After successful compute node install. First boot is hanging with message: TFTP prefix:...
Two examples: backup and restore GitLab docker container with volumes backup and restore only useful data Gitlab is running in Docker...
This example shows how to automate: Creation of two instances sequentially with Terraform on OpenStack cluster. Provisioning new...
RPM package is convenient way to automate consul installation on many RHEL or CentOS servers. But consul rpm is not provided by...
I followed this documentation: https://docs.openstack.org/newton/install-guide-rdo/ Below are mix of issue and how to fix them after...
You cannot create image from a volume in-use. Volume status must be "available" to create image. So: 1. stop instance 2. create...
This post shows how to switch Horizon to HTTPS. Before start you should have working OpenStack Horizon through HTTP. My setup: OS:...
Meaning of this post is to create first simple understanding of the yield. Yield is one of the topics that maybe hard to understand in...
This post is related to the previous one: Kubernetes – simple install on CentOS 7 with Web UI How to reset kubernetes configuration and...
This posts shows working kubernetes setup on CentOS 7.2.1511. Some steps are not covered in other articles on the internet. Current...
Example below shows how to backup on server A and restore docker containers on server B. As example I'll use container created in the...
This example shows LAMP + Wordpress all in one docker container. This setup is not going to scale. And all-in-one makes it easy to...
What we'll do: Install Slave Install Master Adding new slave node on jenkins master Create new project: get files from GitHub archive...
This post shows process of moving MediaWiki to multiple docker containers setup with MySQL master-slave replication. I'll skip MediaWiki...
RSYNC has option --partial (keep partially transferred files) or -P same as --partial --progress. Script below uploads file over ssh and...
Overview Very quick start on CentOS 7.x. Three servers: - master (puppet master) - web (puppet client, httpd and php will be installed)...
This post shows how to create copy of CentOS 7 repositories: base centosplus extras updates epel And configure internal repository...
Install packages: yum -y install httpd xinetd syslinux tftp-server dhcp Copy files from iso image: mount -o loop...
This post shows only commands and file modifications without explanation. It is based on...
Create base image from current CentOS 7 system with one command: tar --numeric-owner --exclude=/proc --exclude=/sys --exclude=/boot...
This post is related to previous post "Vagrant with multiple machines and ports". 1. Backup boxes Remove file 70-persistent-net.rules on...
This post is related to previous post "Vagrant with multiple machines and ports". We configure application and monitoring servers. And...
Vagrant environment: 1. Prepare host system 1.1. Install Unubtu 14.04 x64 on host system. Download page:...
Hadoop setup 3 servers with CentOS 7 minimal installation 64 bit. 192.168.0.100 master.example.com 192.168.0.101 slave01.example.com...
Download and unpack jetty wget http://ftp.heanet.ie/pub/eclipse/jetty/stable-9/dist/jetty-distribution-9.3.3.v20150827.tar.gz tar xzf...
Check health status on OSS # cat /proc/fs/lustre/health_check device lustre-OST0000 reported unhealthy device lustre-OST0001 reported...
OS: CentOS 6.5 Compile MPICH. yum install gcc gcc-gfortran gcc-c++ mkdir /lustre/software cd /lustre/software/ wget...
Install compiler sudo yum install gcc gcc-gfortran gcc-c++ Compile and install MPICH wget...
Manage Active Directory from Linux. Changes on Windows Server 2008 r2 Add new role - Active Directory Certificate Services in Windows...
OS: RHEL 6.x, CentOS 6.x Simultaneous chrooted home via SSH, SFTP and FTP SSHD changes in file /etc/ssh/sshd_config #Subsystem sftp...
OS: CentOS 6.3 MGS server: lustre-mgs IP 192.168.0.1 OSS server: lustre-oss-01 IP 192.168.0.2 Storage: local drive on OSS server...
LVM is not supported by Rocks. But it is possible with additional manual work OS: Rocks 6 Add to a file...
Contents Intro HPL + Intel MKL + Intel MPI HPL + ATLAS + MPICH2 HPL + GotoBLAS2 + Open MPI 0. Intro HPL is a portable implementation of...
Python script executes SQL request and prints output Basic example #!/usr/bin/python import MySQLdb db_connect = MySQLdb.connect(host =...
rrdtool - store and graph data. This example graph memory usage. Source data: free -m total used free shared buffers cached Mem: 499 214...
Network testing without special tools like iperf, netperf and other. On 10 GigE NICs single dd + netcat are limited by one CPU core....
There are special modules for Perl/Python for SSH connection. For example: Net::SSH2::Expect Net::SSH::Expect In BASH can be used SSH...
1. Solaris physical memory usage Script to get free/unused memory on Solaris can be found with command vmstat. Without options, vmstat...
To compare script language for administration tasks. - connect to FTP server in passive mode - delete file - send file in binary mode...
OpenSSH 4.9p1 and higher support user chrooting SSH and SFTP. Latest stable:...
OS: SUSE Linux Enterprise Server 10.2 (x86_64) SF_HS version: 5.0MP3 1. Preinstallation Network: On linux-001 eth0 10.10.10.1 eth1...
To compare script language for administration tasks. Using default installation on Linux (RHEL 5, 6), Solaris (10/9), Mac OS X (10.6.7)....
1. For "HP Smart Array 5i/6i Controller" $ lspci -m | grep RAID 02:02.0 "RAID bus controller" "Compaq Computer Corporation" "Smart Array...
OS: RHEL6 Protocol: TCP Default port: 2049 By default NFS packages are installed. System A (server) IP: 10.10.10.1 $ cat /etc/exports...
OS: RHEL6 Protpcol: UDP Default port: 123 NTP installed by default. System A (server), IP 10.10.10.1 Edit /etc/ntp.conf: # Hosts on...
OS: RHEL 6 Protocol: tcp or/and udp Default port: 514 By default RHEL 6 use rsyslog. System A (server), IP 10.10.10.1 Uncomment lines in...
iSCSI (Internet Small Computer System Interface) - an Internet Protocol (IP)-based to provide data storage over network. Protocol: tcp...
OS: RHEL 6 There is script /usr/sbin/khmel.sh Simple way to build RPM file, that will install this scrip on another systems. Install yum...
Encrypt disk: cryptsetup luksFormat /dev/sdb Create mapper device and file system: cryptsetup luksOpen /dev/sdb testdisk mkfs.ext3...
If user entered his password incorrectly several times his account can be locked. sudo faillog -u khmel Username Failures Maximum Latest...
Backup and restore database, reset password...
1. Scan for new SAN or VMware disk echo "- - -" > /sys/class/scsi_host/host0/scan Replace host0 with actual value. You can find...
Crete Private and Public key on serverA.khmel.org user "phn": ssh-keygen -t rsa without phrase. Simple copy to serverB.phn.org.ua with...
On RHEL 5 with default installed openssh chroot will not allow to login via ssh. (Solution: run separate sshd on another port). To use...
Example: [phn.org.ua ~]$ sudo cat /etc/modprobe.conf . . . alias bond0 bonding file /etc/sysconfig/network-scripts/ifcfg-bond0...
Installation and configuration in command line without GUI. Install yum install xen virt-manager kernel-xen chkconfig xend on reboot...
OS: CentOS 5.4 mdadm — software RAID management tool Raid device names partitions in raid: /dev/md0, /dev/md1 disks in raid: /dev/md_d0,...
Content: Preparation DNS MySQL Postfix with MySQL + SASL2 Dovecot Apache + PostfixAdmin Web Interface (Roundcube) Install Amavisd-new,...
1. Names dn - Distinguished Names cn - Common Name dc - domain component ou - organizational unit uid - user id 2. Install OpenLDAP 2.1....
1. Update ports tree portsnap fetch extract update 2. Install Tomcat 5.5 If TZUPDATE option was chosen, 2 packets should be downloaded...
Special runlevels "s", "emergency", "init=/bin/sh" and single user mode (runlevel 1) Runlevel "1" — will run /etc/rc.d/rc1.d Runlevel...
1. Commands and files: getenforce, setenforce - get and set SELinux mode: Enforcing, Permissive, Disabled....
1. Close all ports except 5130 and 21 IPTABLES='/sbin/iptables' $IPTABLES -A FORWARD -s 192.168.10.164 -p tcp -m tcp --dport 5190 -j...
OS: CentOS 5.4 as XEN guests Command line installation and configuration Disable SELinux abd Firewall: system-config-securitylevel-tui...
To track root actions after: 1. # sudo -s 2. # sudo -i 3. # sudo su - 4. # sudo mc (with \^o) 5. And if some script “vi test.sh” was...
RHEL 6, installation: Citrix client, VPNC, Java, Virtual Box guest drivers. Create repository for Installation DVD [root@localhost ~]#...
Script below will generate HTML report. Report will be sent as HTML email. #!/bin/sh echo "To: phn@khmel.org" > /home/phn/`date...
In log file /var/log/khmel.org.log can be message like: 16.10.2010 00:05:59 KHMEL.ORG site find AASSxxRR0111 connection To convert date...
Example with auto creating user on several servers: ./sshauto.sh ip-list.txt 'hostname; sudo useradd -m -c "PHN user2" -G phn phnname2...
This script add to HTML file strings from another file. And check if these strings already exist. #!/bin/bash AddNewString() {...
#!/bin/bash HOST='phn.org.ua' USER='phn' PASSWD='PhnPassw0rd!' ftp -p -n -v $HOST << EOT ascii user $USER $PASSWD prompt cd www # Only...
Contents Configuration files Configuration tools Network console tools Firewall files and tools Enable temporary telnet connection on...
Without public key GPG # encrypt gpg -c khmel.tar.gz # decrypt gpg khmel.tar.gz.gpg OpenSSL # encrypt openssl des3 -salt -in...
First LVM commands to get overview on server: pvs # report information about physical volumes vgs # report information about volume...
Install: yum install vsftpd Change settings /etc/vsftpd/vsftpd.conf: anonymous_enable=YES local_enable=YES write_enable=YES...
Install mpd: pkg_add -r mpd # or cd /usr/ports/net/mpd make && make install If external IP: 123.123.123.123 VPN IP: 10.10.10.0...
Step-by-step operations in command line to setup Soft RAID. Before setup: sysctl kern.geom.debugflags=16 To create mirroring on disk...
Solution #1: firewall rules: FwCMD="/sbin/ipfw" outip="123.123.123.123" httpserver="192.168.1.2" NetIn="192.168.1.0" NetMask="24"...
Server Install cd /usr/ports/security/openvpn make install Add to /etc/rc.conf openvpn_enable="YES" Configuration file cd...
OS: Debian 3.1 r4 We need latest stable kernel source to compile modified kernel, now it is linux-2.6.19.1 cd /usr/src ftp...
Secure data transferring via Web OS: Debian GNU/Linux 3.1 r0a "Sarge" FreeBSD 5.4-RC1-i386 Packages: OpenSSL apache+mod_ssl Create SSL...
Linux Reset root password on Linux (RHEL/CentOS). Grub or Lilo should be without password or you should know that password. In GRUB menu...
/etc/bind/named.conf options { listen-on port 53 { 127.0.0.1; 192.168.2.1; server-ip; }; allow-recursion { 127.0.0.1; 192.168.2.0/24; };...
Example: mail box me\@khmel.org, login: "me", password: "testpass". 1. Send e-mail # Connect to server on TCP 25 port $ telnet...
Postfix Main config file /etc/postfix/main.cf, with only 2 lines: mydestination = khmel.org home_mailbox = Maildir/ Create user test:...