psql: FATAL: Ident authentication failed for user (Centos 7)

What's up?

In this article you will know how to fix this error:

psql: FATAL:  Ident authentication failed for user "username"

which happens when you try to connect as follows:

psql -U username -h 127.0.0.1 -d postgres

How to install/upgrade postgresql server from 9.2 to 9.6 on Centos 7

Hello!

This tutorial includes detailed steps on how to upgrade from old 9.2 postgresql server to new 9.6 postgresql server, with data migration. But you can also use this article if you want to install fresh 9.6 version - you just need to skip migration steps. You can also check this link for more information.

1. install PGDG RPM file for new postgresql server

sudo yum install https://download.postgresql.org/pub/repos/yum/9.6/redhat/rhel-7-x86_64/pgdg-centos96-9.6-3.noarch.rpm

(for the list of all options, check this link: https://yum.postgresql.org/repopackages.php)

How to install latest version of nginx in Centos 7

As of now current nginx version in centos 7 repo is 1.12.2, but latest version of stable nginx is 1.14.1.

In this article we will install latest nginx/1.14.1 in Centos 7.

1. Remove current version of nginx (1.12.2)

sudo yum remove nginx*

How to install python 3.5 in CentOS 7 from source

At the time of writing, repository of Centos 7 contains python 3 of version 3.4, which is not the newest. And sometimes it's useful to have newer version. For example, I needed python 3.5. And here I will show you how to install it. We will be installing it from source.

1. Update repositories and install couple packages:

sudo yum update
sudo yum install zlib-devel openssl-devel