Category: Documentation

Setting Up Infiniband in Centos 6.7

Installing Infiniband Drivers In Centos/RHEL, software support for Mellanox infiniband hardware is found in the package group “Infiniband Support”, which can be installed with yum: $yum -y groupinstall “Infiniband Support” This will install the required kernel modules, and the infiniband subnet manager opensm. Several optional packages are also available that make configuring and trouble shooting the network easier: $yum -y install infiniband-diags perftest gperf inifiniband-diags is a network diagnostic package containing useful analysis tools such as ibping and ibstat. perftest...

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How to Install CentOS 6 Minimum Without Internet

When I first installed CentOS 6 minimum, I couldn’t figure out how to install the OS without internet connection, but eventually, I figured it out. The OS that I’m using is CentOS 6.7 minimum, and normally, you’d need Internet connection while installing the OS because you would select URL for the installation method. To create the bootable USB flash drive, I’ve created a blog post for the instructions. Insert a bootable USB flash drive into the machine and boot into CentOS...

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How to Mount USB Flash Drive on CentOS 7

In this blog article, I’ll show you how to mount a USB Flash Drive on CentOS 7 terminal. In my case, I needed to mount a USB Flash Drive on my minimal CentOS 7 machine to copy a file to the USB Flash Drive. USB Flash Drive The file system of my USB flash drive is FAT32. I used a Windows 10 computer to create a folder called System Volume Information on the USB flash drive. Mounting First, go to your...

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How to Run HPL (LINPACK) Across Nodes – Guide

We’ve been working on a benchmark called HPL also known as High Performance LINPACK on our cluster. Our cluster is made of 6 nodes. The specs are: 6 x86 nodes each with an Intel(R) Xeon (R) CPU 5140 @ 2.33 GHz, 4 cores, and no accelerators. Our OS is CentOS 7. At first, we had difficulty improving HPL performance across nodes. For some reason, we would get the same performance with 1 node compared to 6 nodes. Here’s what we...

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How to Install Ansible on CentOS 7

Ansible is a useful configuration automation software that allows you to automate the setup of your machines. In comparison to other configuration automation out there like Chef or Puppet, I’ve found it to be much simpler to use for cluster setup. Installation First, I normally update the EPEL on CentOS 7 before installing ansible. yum install epel-release Afterwards, we can use yum install to setup ansible on our machine. If you have a cluster, install ansible on each individual node....

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How to Install Our Cluster Dependencies for CentOS 6 Locally

We’re going to ASC16 in China for a student cluster competition, but we won’t have internet access on the cluster, so we need to download all  the dependencies beforehand. First, we have a SSD that we’ll download all the things that we need for the server and clients. Install CentOS 6.7 minimum Make directories on the SSD Download dependencies for server and clients on SSD Install CentOS 6.7 minimum First, we installed CentOS 6.7 minimum before we left for the competition....

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How to Download and Install Yum Packages Locally

On CentOS, we sometimes need to install yum packages as RPMs locally because we may need them at a time when we don’t have internet access. How to Download Yum Packages Locally Option #1 I like to use yum-downloadonly to download packages locally. yum install yum-plugin-downloadonly Make a directory where you will download the RPMs. mkdir /nfs Now, we use –downloadonly to download all the RPMs of the package and its dependencies into the /nfs directory. yum install git -y...

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Sending Messages to Linux Users without Sudo

This may or may not work depending on the security preferences of the machine, but usually, you can use these commands even if you do not have sudo. To broadcast a message to all users: wall hello All users currently on the machine would receive: Broadcast message from root@domain (pts/2) (Wed Apr 6 12:53:22 2016): hello To send messages directly to a user: who winstonc pts/247 Apr 6 12:04 (107-46-41-155-wireless1x.bu.edu) huyle333 pts/249 Apr 6 12:07 (162-38-41-155-wireless1x.bu.edu) Let’s say that I’m...

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How to Install Slurm on CentOS 7 Cluster

Slurm is an open-source workload manager designed for Linux clusters of all sizes. It’s a great system for queuing jobs for your HPC applications. I’m going to show you how to install Slurm on a CentOS 7 cluster. Delete failed installation of Slurm Install MariaDB Create the global users Install  Munge Install Slurm Use Slurm Cluster Server and Compute Nodes I configured our nodes with the following hostnames using these steps. Our server is: buhpc3 The clients are: buhpc1 buhpc2...

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How to Add Subdomains on Namecheap

Adding subdomains on Namecheap is quick and easy. Let’s say that I have a remote computer with IP address, 128.197.115.158. I want to be able to SSH into this machine, but I hate needing to remember the IP address. Well, if you have purchased a website domain name on Namecheap like I have, just add a subdomain to your website! One of my websites that I have registered with Namecheap is http://buhpc.com, so I’ll be using that as the example.  ...

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