Install and Enable EPEL Repository for CentOS 7.x

The EPEL is an acronym for Extra Packages for Enterprise Linux. The EPEL repository used by the following Linux Distributions:

  • Red Hat Enterprise Linux (RHEL)
  • CentOS
  • Oracle Linux

On the Terminal,

Install EPEL Repository

# yum -y install epel-release

Refresh EPEL Repository

# yum repolist

Install Packages from EPEL Repository

# yum install -y htop

Search and install Package (E.g. htop)

# yum --disablerepo="*" --enablerepo="epel" list available | grep 'htop'

Basic CURL Commands

curl is a command line tool to transfer data to or from a server. It is able to use any of the supported protocols like HTTP, FTP, IMAP, POP3, SCP, SFTP, SMTP, TFTP, TELNET, LDAP or FILE. This tool is very useful for automation, since it is designed to work without user interaction. Furthermore, curl can transfer multiple file at once.

Basic Single URL Usage

% curl https://thelinuxcluster.com/

2a. Save the Download File with a preferred file name

Save the Download File on the local machine with the name provided with the parameter.

% curl -o test.o https://thelinuxcluster.com/test.output

2b. Save the Download File

% curl -O https://thelinuxcluster.com/test.output

2c. Download Multiple Files. Just Multiple -O

% curl -O https://thelinuxcluster.com/CentOS1.iso -O https://thelinuxcluster.com/CentOS2.iso -O https://thelinuxcluster.com/CentOS3.iso

3a. Display a Progress Meter

% curl --progress-bar -o test.o https://thelinuxcluster.com/test.output 

3b. Do not display a Progressive Bar

% curl --silent -o test.o https://thelinuxcluster.com/test.output

4 Limit Rate of Data Transfer

% curl --limit-rate 1000K -o test.o https://thelinuxcluster.com/CentOS1.iso

5a Uploading a File to the FTP Server

% curl -u username:userpassword -T myfile ftp://ftp.thelinuxcluster.com/

5b. Appending the File to the FTP Server

% curl -u username:userpassword -a -T myfile ftp://ftp.thelinuxcluster.com/

5c Downloading the File to the File Server

% curl ftp:/ftp.thelinuxcluster.com/CentOS79.iso --user username:userpassword -o myCentOS79.iso

6a. Verifying SSL Certificate

% curl --cacert server.crt https://thesupersecureserver.com

6b. Ignoring SSL Certificate

% curl -k https://thesupersecureserver.com/

7a Proxy Server

% curl -x proxy_name:proxy_port https://thelinuxcluster.com

7b Proxy Server which requires authentication

% curl --user username:userpassword -x proxy_name:proxy_port https://thelinuxcluster.com 

8 Sending Email

% curl --url "smtps"//smtp.thelinuxcluster.com:465: --ssl-reqd --mail-from "sender@thelinuxcluster.com" --mail-rcpt "receiver@thelinuxcluster.com" --upload-file maincontent.txt --user "sender@thelinuxcluster.com:password" --insecure

References:

  1. Learn to use CURL command with examples
  2. Curl command in Linux with Examples

No-Cost, Self-Supported RHEL up to 16 systems under Individual Developer Subscription for RHEL

From RHEL, “No-cost RHEL for small production workloads and customer development teams

We’re addressing this by expanding the terms of the Red Hat Developer program so that the Individual Developer subscription for RHEL can be
used in production for up to 16 systems. That’s exactly what it sounds like: for small production use cases, this is no-cost, self-supported RHEL.
You need only to sign in with a free Red Hat account (or via single sign-on through GitHub, Twitter, Facebook, and other accounts) to download
RHEL and receive updates. Nothing else is required. This isn’t a sales program and no sales representative will follow up. An option will exist within
the subscription to easily upgrade to full support, but that’s up to you.

……

The updated Individual Developer subscription for RHEL will be available no later than February 1, 2021.