Monthly Archives: June 2018

How to install ElasticSearch on CentOS 7

“Elasticsearch is a search engine based on Lucene. It provides a distributed, multitenant-capable full-text search engine with an HTTP web interface and schema-free JSON documents. Elasticsearch is developed in Java and is released as open source under the terms of the Apache License”

This tutorial will show you how to install ElasticSearch on CentOS 7. The version of ElaistcSearch we use is, 1.7.3.

Step 1

We download openJDK by running:

sudo yum install java-1.8.0-openjdk.x86_64

Step 2

Next we will get the elasticsearch package by running:

sudo wget https://download.elastic.co/elasticsearch/elasticsearch/elasticsearch-1.7.3.noarch.rpm

Step 3

We will then install it by running the following command:

sudo rpm -ivh elasticsearch-1.7.3.noarch.rpm

Step 4

We will then start and configure the elasticsearch service by running the following commands.

sudo service elasticsearch start
sudo service elasticsearch status
sudo chkconfig elasticsearch on

Step 5

We will now check that elasticsearch is working as we expect. We will navigate to localhost over port 9200 (the default port for elasticsearch)

sudo wegt localhost:9200
cat index.html

The output of this file should look similar to the below.

{
"status" : 200,
"name" : "Lockjaw",
"cluster_name" : "elasticsearch",
"version" : {
"number" : "1.7.3",
"build_hash" : "05d4530971ef0ea46d0f4fa6ee64dbc8df659682",
"build_timestamp" : "2015-10-15T09:14:17Z",
"build_snapshot" : false,
"lucene_version" : "4.10.4"
},
"tagline" : "You Know, for Search"
}

A full video tutorial can be found here:

How to run a command on Startup on Linux (works on CentOS & Ubuntu)

4 Replies

Hi there,

In this example I had a need to record boot up times in a file that i could access easily. To do so I decided to run a command on startup. This tutorial tool place on CentOS but the commands should also work on Ubuntu.

Step 1

Edit the rc.local file in vi by running:

sudo vi /etc/rc.local

Step 2

Add the following line to the file, update the home directory to represent your home directory.

Press i to go into insert mode
Enter the line:
- echo “the computer booted up at” `date` >> /home/darren/bootup.log
Press ESC and then wq! and enter to save and quit the file.

Step 3

Give the executable permission to the rc.local file by running the following command:

chmod +x /etc/rc.d/rc.local

Step 4

Reboot the system by running:

sudo init 6

Step 5

When the machine reboots run the following command to insure the file has been created and that there is content in the file:

cat /home/darren/bootup.log

A full video tutorial can be found here:

How to install VirtualBox on Windows Server 2016 / Windows 10

VirtualBox host only adaptor disappeared (Interface (‘VirtualBox Host-Only Ethernet Adapter’) is not a Host-Only Adapter interface (VERR_INTERNAL_ERROR) SOLVED

6 Replies

Hi there,

After recently updating Windows 10, none of my VMs in VirtualBox would power on. I kept receiving an error that read:

(Interface (‘VirtualBox Host-Only Ethernet Adapter’) is not a Host-Only Adapter interface (VERR_INTERNAL_ERROR) SOLVED

After looking around the settings of my Windows 10 machine I noticed that the host only adaptor was missing. To fix it I added a new adaptor by doing the following:

Step 1

I clicked file and then Host Network Manager

Step 2

In the screen that appears I then clicked Create, to create a new Host Only Network.

Step 3

I then right clicked on the VM i wanted to start and clicked settings.

Step 4

I then did the following:

Clicked on Network.
Selected the checkbox to enable Network adaptor.
Assigned the Host only adaptor I created.
I then clicked ok.

The VM then booted without issue.

A full video Tutorial can be found here: