In this
article, I have explained about PostgreSQL Database 12.1 installation in Red
Hat Linux / CentOS
·
PostgreSQL is
an open-source database management system.
·
It is designed
to run on different platforms.
·
Its source
code is available under PostgreSQL license.
- PostgreSQL supports both SQL for relational and NoSQL
for non-relational queries.
- Rpm, yum, source installation methods are explained in the PostgreSQL database
2
The Hardware Requirement
2.1
Memory Requirement
The minimum requirement of physical RAM is 2GB.
RAM Memory:
The minimum requirement for memory.
$ grep MemTotal /proc/meminfo
Swap
Memory:
$ grep SwapTotal /proc/meminfo
2.2
System architecture
The
system architecture of the OS is 64bit
$ uname -m
2.3
Disk space Requirement
The tmp directory
should contain a free disk space of 1GB or more.
$ df -h /tmp
3
The Software Requirement
3.1
Operating system Requirement
The
OS version is Red Hat Enterprise Linux 7/8 and centos.
The kernel version is 2.6.32
$ cat /proc/version
3.2
Package Requirement
The
following are the installed packages with version.
(In PostgreSQL Database 12 prior
to release 12.1.0, package both 64-bit and 32-bit shown in the following table
is required.)
$ Rpm-q package
postgres
rpm -ivh
postgresql12-libs-12.1-1 PGDG.rhel7.x86_64.rpm
rpm -ivh
postgresql12-12.1-1PGDG.rhel7.x86_64.rpm
rpm -ivh
postgresql12-contrib-12.1-1PGDG.rhel7.x86_64.rpm
rpm -ivh
postgresql12-server-12.1-1PGDG.rhel7.x86_64.rpm
4
Installation
We can install PostgreSQL using any one of the below types.
(1) RPM-Manual
Installation
If you cannot, or do not want to, use the yum-based
installation method, all the RPMs that are in the yum repository are available
for direct
download and manual installation
as well.
(2) YUM
-Online Installation
The PostgreSQL Yum Repository will integrate with your normal systems and patch
management, and provide automatic updates for all supported versions of
PostgreSQL throughout the supported lifetime of PostgreSQL.
The PostgreSQL Yum Repository
currently supports:
·
Red Hat
Enterprise Linux
·
CentOS
·
Scientific
Linux
·
Postgres Linux
·
Fedora*
(3) SOURCE
- Requirement Installation
Using make, make all commands
we can create new source based on our requirement
4.1
Rpm Installation
4.1.1 Pre-request
(Enter the root user)
1)Data path and user creation:
Create “postgres“user
Useradd postgres
Passwd postgres
Create data path /var/lib/data12pgsql
Chmod -R 755 data12pgsql/
Chown -R postgres. data12pgsql/
2).bin path creation:
Created bin path automatically in /usr while initdb start
4.1.2 Postgresql 12.1 Installation steps
Step:1 Download and
install Repo
Link : https://yum.postgresql.org/12/redhat/rhel-7-x86_64/
[root@svgen Software]# rpm -ivh
pgdg-redhat-repo-42.0-11.noarch.rpm
Preparing... ################################# [100%]
Step:2 Download the needed
“Rpm”from below link
Link:https://download.postgresql.org/pub/repos/yum/12/redhat/rhel-7-x86_64/
[root@gokul Postgres_sw]# Rpm are
saved in the “Postgres_sw” directory
rpm -ivh postgresql12-libs-12.1-1
PGDG.rhel7.x86_64.rpm
rpm -ivh
postgresql12-12.1-1PGDG.rhel7.x86_64.rpm
rpm -ivh
postgresql12-contrib-12.1-1PGDG.rhel7.x86_64.rpm
rpm -ivh
postgresql12-server-12.1-1PGDG.rhel7.x86_64.rpm
Step:3
Switch user su - postgres
[postgres@gokul ~]$
/usr/pgsql-12/bin/initdb -D /var/lib/data12pgsql
The files belonging to this database system will be owned
by user "postgres".
This user must also own the server process.
The database cluster will be initialized with locale
"en_US.UTF-8".
The default database encoding has accordingly been set to
"UTF8".
The default text search configuration will be set to
"english".
Data page checksums are disabled.
Success. You can now start the database server using:
/usr/pgsql-12/bin/pg_ctl -D
/var/lib/data12pgsql -l logfile start
Step:4
Start the service
/usr/pgsql-12/bin/pg_ctl -D
/var/lib/data12pgsql status
/usr/pgsql-12/bin/pg_ctl -D
/var/lib/data12pgsql start
/usr/pgsql-12/bin/pg_ctl -D
/var/lib/data12pgsql stop
[postgres@gokul ~]$ /usr/pgsql-12/bin/pg_ctl -D
/var/lib/data12pgsql start
server started
Step:5 Connect the database
4.1.3 Post
Installation – Configuration
cd /var/lib/data12pgsql
vi pg_hba.conf
# IPv4 local connections:
host all all ::1/128 ident
host all all 0.0.0.0/0 trust
vi postgresql.conf
listen_addresses
= '10.1.4.45' # what IP
address(es) to listen on;
port =
5432 # (change requires restart)
max_connections
= 100 # (change
requires restart)
Note:After
configuration file edited we must restart the service for changes replication.
Step:7 Remote Access
4.2
Yum Installation
To use the PostgreSQL Yum
Repository, follow these steps:
/usr/pgsql-12/bin/postgresql-12-setup initdb
systemctl enable postgresql-12.service
systemctl start postgresql-12.service
4.2.1 Post
Installation – Configuration
cd
/var/lib/psql/12/datal
vi pg_hba.conf
# IPv4
local connections:
host all all ::1/128 ident
host all all 0.0.0.0/0 trust
vi postgresql.conf
listen_addresses
= '10.1.4.78' # what IP
address(es) to listen on;
port =
5432 # (change requires restart)
max_connections
= 300 # (change
requires restart)
Note:After configuration
file edited we must restart the service for changes replication.
Remote
Access
4.3
Source Installation
Step:1:
Step:2
STEP:3
Place the file in
/opt/source location.
[root@postgres source]# pwd
/opt/source
Unzip the tar file:
[root@ postgres source]# tar -zxvf postgresql-12.0.tar.gz
Step:4
[root@postgres source]# ll
drwxrwxrwx. 6 1107 1107 4096
Jan 31 14:43 postgresql-12.0
-rw-r--r--. 1 root root 26393892
Jan 31 13:01
postgresql-12.0.tar.gz
[root@postgres source]# cd postgresql-12.0/
Step:5
[root@postgres postgresql-12.0]#
ll
total 1204
drwxrwxrwx. 2 1107 1107 4096 Oct
1 01:39 config
Step:6
./configure --prefix=/var/lib/pg1sql
Step:7
make
make install
Step:8
mkdir /var/lib/data
chmod 700 /data
chown -R postgres. Data
Step:9
su - postgres
cd /var/lib/pg1sql/bin
-bash-4.2$ cd pg1sql/
-bash-4.2$ ll
drwxr-xr-x. 2 root root 4096 Jan 31 14:50 bin
-bash-4.2$ cd bin/
-bash-4.2$ ll
-rwxr-xr-x. 1 root root 142520
Jan 31 14:50 initdb
Step:10
.-bash-4.2$ ./initdb -D /var/lib/data
Step:11
-bash-4.2$ ./pg_ctl --help
pg_ctl is
a utility to initialize, start, stop, or control a PostgreSQL server.
Usage:
pg_ctl init[db] [-D DATADIR]
[-s] [-o OPTIONS]
pg_ctl start [-D DATADIR] [-l FILENAME] [-W] [-t SECS]
[-s]
[-o OPTIONS] [-p PATH] [-c]
pg_ctl stop [-D DATADIR] [-m SHUTDOWN-MODE] [-W] [-t
SECS] [-s]
pg_ctl restart [-D DATADIR] [-m SHUTDOWN-MODE] [-W] [-t
SECS] [-s]
[-o OPTIONS] [-c]
pg_ctl reload [-D DATADIR] [-s]
pg_ctl status [-D DATADIR]
pg_ctl promote [-D DATADIR] [-W] [-t SECS] [-s]
pg_ctl logrotate [-D DATADIR] [-s]
pg_ctl kill SIGNALNAME PID
Common options:
-D, --pgdata=DATADIR location of the database storage area
-s, --silent only print errors, no informational
messages
-t, --timeout=SECS seconds to wait when using -w option
-V, --version output version information, then exit
-w, --wait wait until operation completes
(default)
-W, --no-wait do not wait until operation completes
-?, --help show this help, then exit
If the -D
option is omitted, the environment variable PGDATA is used.
Options for stop or restart:
-m,
--mode=MODE MODE can be
"smart", "fast", or "immediate"
Shutdown modes are:
Smart -
quit after all clients have disconnected
Fast -
quit directly, with proper shutdown (default)
Immediate - quit without
complete shutdown; will lead to recovery on restart
Allowed signal names for kill:
ABRT HUP INT KILL
QUIT TERM USR1 USR2
Step:12
HOW TO
STOP SERVICE:
-bash-4.2$ pwd
/var/lib/pg1sql/bin
postgres-# \q
-bash-4.2$ ./pg_ctl -D /var/lib/data stop
waiting for server to shut down.... done
server stopped
Step:13
HOW TO
START SERVICE:
-bash-4.2$ ./pg_ctl -D /var/lib/data start
waiting for server to start....2020-02-03 17:57:07.810 IST [10281]
LOG: starting PostgreSQL 12.0 on
x86_64-pc-linux-gnu, compiled by gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-39),
64-bit
2020-02-03 17:57:07.810 IST [10281] LOG: listening on IPv4 address "10.1.4.88",
port 5432
2020-02-03 17:57:07.811 IST [10281] LOG: listening on Unix socket
"/tmp/.s.PGSQL.5432"
2020-02-03 17:57:07.820 IST [10282] LOG: database system was shut down at 2020-02-03
17:54:01 IST
2020-02-03 17:57:07.826 IST [10281] LOG: database system is ready to accept
connections
done
server started
Step:14
HOW TO
STATUS SERVICE:
-bash-4.2$ ./pg_ctl -D /var/lib/data status
pg_ctl: server is running (PID: 10281)
/var/lib/pg1sql/bin/postgres "-D" "/var/lib/data"
Step:15
postgres 7125 7124 0 14:34 pts/1 00:00:00 -bash OS LEVEL FIND OUT SERVICE
STATUS
[root@postgres source]# ps -ef
|grep postgres
postgres 10281 1
0 17:57 ? 00:00:00
/var/lib/pg1sql/bin/postgres -D /var/lib/data
Step:16
-bash-4.2$ ./pg_ctl -D /var/lib/data status
pg_ctl: server is running (PID: 10281)
/var/lib/pg1sql/bin/postgres "-D" "/var/lib/data"
-bash-4.2$ ./psql -p 5432
psql (12.0)
Type "help" for help.
postgres=#
Step:17
postgres=# \l
List of database
postgres=# \dn
List of schemas
4.3.1 Post Installation –
Configuration
cd /var/lib/psql/12/datal
vi pg_hba.conf
# IPv4 local connections:
host all all ::1/128 ident
host all all 0.0.0.0/0 trust
vi postgresql.conf
listen_addresses = '10.1.4.78'
# what IP address(es) to listen on;
port = 5432
# (change requires restart)
max_connections = 300 # (change requires
restart)
Note: After the configuration file is edited we must restart the service for changes replication.
Remote
Access
5
Postgresql Uninstall
Pre-Request for uninstalling
1). Enter
the Postgres user and we need to stop the postmaster service.
2).
Remove the list of rpm
3).
Remove the bin path and data-path
4).
Remove the Postgres user
Step:1 stop the service
[postgres@gokul ~]$ /usr/pgsql-11/bin/pg_ctl -D /var/lib/datapg11.7 status
pg_ctl: server is running (PID: 2236)
/usr/pgsql-11/bin/postgres
"-D" "/var/lib/datapg11.7"
[postgres@gokul ~]$ /usr/pgsql-11/bin/pg_ctl -D /var/lib/datapg11.7 stop
waiting for server to shut down....
done
server
stopped
Step:2 remove rpm from gokul Environment
[root@gokul ~]# rpm -qa | grep postgres
postgresql11-libs-11.7-1PGDG.rhel7.x86_64
postgresql11-11.7-1PGDG.rhel7.x86_64
postgresql11-server-11.7-1PGDG.rhel7.x86_64
postgresql11-contrib-11.7-1PGDG.rhel7.x86_64
[root@gokul ~]#rpm -e postgresql11-11.7-1PGDG.rhel7.x86_64
[root@gokul ~]#rpm -e postgresql11-server-11.7-1PGDG.rhel7.x86_64
[root@gokul ~]#rpm -e
postgresql11-libs-11.7-1PGDG.rhel7.x86_64
[root@gokul ~]#rpm -e
postgresql11-contrib-11.7-1PGDG.rhel7.x86_64
Step:3 Enter the “root” user remove the bin path and data
path from gokul environment
Bin path removal:
[root@gokul ~]# cd /usr
[root@gokul usr]# rm -rf pgsql-11
Data path removal:
[root@gokul ~]# cd /var/lib
[root@gokul lib]# rm -rf datapg11.7
Step: 4 Removal of postgres user
[root@gokul ~]# userdel -r postgres
Successfully
uninstalled 11.7 version
