# Updating standalone PostgreSQL 12 and lower to version 18

> [HTML Version](upgrading-postgresql-standalone-10-to-15.html)

When updating PostgreSQL to a major version, the utility \[OBJECT\] is used. It allows updating the data stored in PostgreSQL data files to a later version of PostgreSQL.

The update of standalone PostgreSQL consists of six steps:

1. [Database backup](#database-backup).

2. [Installation of PostgreSQL 18](#install-postgresql15).

3. [Updating data in the database directory](#updating-data).

4. [Configuration update](#updating-configuration).

5. [Post-installation check](#check-after-installing).

## Step 1. Database backup

Before performing any actions related to the update, create a backup of the data and PostgreSQL configuration. Read more about how to do this in [Backup and recover databases](database-backup-and-recovery.md).

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начало внимание

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If there are third-party databases on the PostgreSQL server, their backups also need to be created.

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конец внимание

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Backup of the PostgreSQL database without using the brix365-backupper utility

  
You can create a backup of the \[OBJECT\] database using the \[OBJECT\]:



````
sudo -u postgres pg\_dump brix365 -Fc > path/to/brix365.bak 
````

## ````
Step 2. Installation of PostgreSQL 18

Use the package manager of your operating system to install PostgreSQL 18 on the server where version 12 or lower is installed:

````
sudo apt install postgresql-18

## ````
Step 3. Updating data in the database directory

1. Stop PostgreSQL to keep its data inaccessible during the update. In this example version 12 is updated to version 18:

````
sudo systemctl stop postgresql@12 postgresql@18

2. ````
Ensure that both PostgreSQL 12 or lower and PostgreSQL 18 clusters are stopped:

````
pg\_lsclusters

3. ````
On the server, perform a check for database configuration compatibility:

````
sudo -iu postgres /usr/lib/postgresql/18/bin/pg\_upgrade \\  
\-o "-c config\_file=/etc/postgresql/12/main/postgresql.conf" \\  
\-O "-c config\_file=/etc/postgresql/18/main/postgresql.conf" \\  
\--old-datadir=/var/lib/postgresql/12/main/ \\  
\--new-datadir=/var/lib/postgresql/18/main/ \\  
\--old-bindir=/usr/lib/postgresql/12/bin \\  
\--new-bindir=/usr/lib/postgresql/18/bin --check

````
Where:

- \[OBJECT\] and \[OBJECT\] are the paths to the binary files of PostgreSQL versions 12 and 18.

- \[OBJECT\] and \[OBJECT\] are the paths to the data directories.

4. On the server, perform the transfer of data from PostgreSQL 12 or lower to PostgreSQL 18:

````
sudo -iu postgres /usr/lib/postgresql/18/bin/pg\_upgrade \\  
\-o "-c config\_file=/etc/postgresql/12/main/postgresql.conf" \\  
\-O "-c config\_file=/etc/postgresql/18/main/postgresql.conf" \\  
\--old-datadir=/var/lib/postgresql/12/main/ \\  
\--new-datadir=/var/lib/postgresql/18/main/ \\  
\--old-bindir=/usr/lib/postgresql/12/bin \\  
\--new-bindir=/usr/lib/postgresql/18/bin

````
Where:

- \[OBJECT\] and \[OBJECT\] are the paths to the binary files of PostgreSQL versions 12 and 18.

- \[OBJECT\] and \[OBJECT\] are the paths to the data directories.

## Step 4. Configuration update

1. Update the PostgreSQL 18 configuration settings according to the configuration used in PostgreSQL 12 or lower:

````
sudo nano /etc/postgresql/18/main/postgresql.conf  
sudo nano /etc/postgresql/18/main/pg\_hba.conf

2. ````
Run PostgreSQL 18:

````
sudo systemctl start postgresql@18

## ````
Step 5. Post-installation check

1. Check PostgreSQL database status:

````
sudo systemctl status postgresql

2. ````
Ensure that PostgreSQL server is ready to receive connections from clients: 

````
sudo pg\_isready
````