Backup

Shutdown the Confluence server that you want to backup. Then execute the following commands

sudo -u postgres pg_dump confluence > confluence.sql
tar -czvf confluence.tar.gz /var/atlassian/application-data/confluence

Install Empty Confluence Server

Install a fresh confluence server in the target machine (choosing all defaults):

./atlassian-confluence-7.13.0-x64.bin

Install Postgres and create a empty confluence database

sudo apt-get install postgresql postgresql-contrib
sudo -u postgres psql
CREATE USER confluenceuser WITH PASSWORD 'password';
CREATE DATABASE confluence ENCODING 'UTF8' LC_COLLATE = 'en_US.UTF-8' LC_CTYPE = 'en_US.UTF-8' TEMPLATE template0;
grant all privileges on database confluence to confluenceuser;

Go through the Confluence wizard setup process:

• choose empty confluence

Restore Data onto Empty Confluence Server

Shutdown empty confluence server.

Restore Postgres data with confluence.sql

dropdb confluence_db_name_here
createdb confluence_db_name_here
sudo -u postgres psql confluence_db_name_here < confluence.sql

Restore Confluence home folder by replacing the whole directory /var/atlassian/application-data/confluence with confluence.tar.gz

tar -xf confluence.tar.gz
mv /var/atlassian/application-data/confluence /var/atlassian/application-data/confluence-initial
mv confluence /var/atlassian/application-data

Ensure all files and directories are owned by confluence user

sudo chown -R <confluence-user> <confluence-install-folder>
sudo chown -R <confluence-user> <confluence-home-folder>
sudo chmod -R u=rwx,g=rx,o=rx <confluence-install-folder>
sudo chmod -R u=rwx,g=rx,o=rx <confluence-home-folder>