Tagged: CentOS 7

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...


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....


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...


How to Install GlusterFS on CentOS 7

GlusterFS is a scale-out network-attached storage file system. In this tutorial, we’ll be setting up GlusterFS on a cluster with CentOS 7.  Our cluster has 6 nodes connected through a switch. I’ll be using all 6 nodes as servers for distributed replicated storage with opportunity for more nodes to be clients that can access files from the GlusterFS servers. How does GlusterFS work In a GlusterFS, servers are used to store data in a distributed manner, and clients can access...


How to Install Ganglia on CentOS 7

Ganglia is a scalable distributed monitoring system for high-performance computing systems such as clusters and Grids. Ganglia is useful when monitoring nodes of a cluster. Setting up Ganglia on CentOS 7 with a bunch of nodes can be confusing. In this blog, I’ll show you how to setup Ganglia and its web interface properly. Our cluster has 6 nodes connected through a switch. Cluster Server and Clients I configured our nodes with the following hostnames using these steps. Our server...


How to Fix yum Could not resolve host: repo Unknown error

You may receive a problem with yum not being able to resolve hosts when you try to install a yum package. I’m using CentOS 7. yum install wget

If you already have Internet connection and can ping, the likely problem is that you don’t have nameservers in your /etc/resolv.conf. vi /etc/resolv.conf If /etc/resolv.conf does not have any nameservers, you can add this line somewhere in the file: nameserver Note: if you have used dhclient command, you should...


How to Change hostname on CentOS 7

The best way to change hostname on CentOS 7 is editing the actual file that controls the hostname. vi /etc/hostname Originally, it is: localhost.localdomain But, we’ll delete that line and change it to: buhpc2 buhpc is our hostname, but it also has the subdomain, 2.buhpc.com, that I have configured. Now, the second file that we also have to change is /etc/hosts. vi /etc/hosts The original file looks like:

You create a new line with IP address hostname subdomain. If...


How to Set Static IP Address on CentOS 7

This blog post will show you how to set a static IP address on CentOS 7 from scratch with no prior knowledge of any information about the network. See if NetworkManager is running. NetworkManager is a network daemon that handles our network interfaces dynamically, but we’ll change our network scripts to set static configurations. We should stop this service. systemctl status NetworkManager systemctl stop NetworkManager Check what interfaces are available. nmcli d

Connect your Ethernet cable into the computer.  ...


How to Install CentOS 7 Minimal Without a Mouse on Troubleshooting Basic Graphics Mode

Here are the list of steps to install CentOS 7 minimal without a mouse on a node or computer with no apparent graphics card. Why do we have to use troubleshooting mode? Without the graphics card, the node or machine tends to freeze at setup because there is no graphics card to render the setup properly, so we have to use troubleshooting mode and take advantage of installing CentOS 7 in basic graphics mode.   Steps First, follow Create Bootable USB...


How to Create Bootable USB Flash Drive of CentOS 7 Minimal ISO

This article will provide the step to step instructions to create a bootable USB flash drive of CentOS 7 Minimal ISO on Windows, Mac, or Linux. The CentOS instance that we will install onto the bootable USB flash drive is CentOS-7-x86_64-Minimal-1503-01.iso.   Requirements Windows: You will need to use a program like Cygwin. I have another blog post, teaching how to install Cygwin on Windows machines. Macs and Linux: Your terminal will have the command already as a part of the...