PostgreSQL 12 High Availability Cookbook - Third Edition

How to do it...

For the purposes of this recipe, we will assume that the /dev/VG_DRBD/LV_DATA device already exists. The two PostgreSQL nodes for this example are named pg1 and pg2 and are located on the 10.0.30.0 subnet. Follow these steps as the root user on each server to add DRBD:

1. Create a file named /etc/drbd.d/pg.res with the following content:

resource pg { 
  device minor 0; 
  disk /dev/VG_DRBD/LV_DATA; 
  meta-disk internal; 
  on pg1 { 
    address 10.0.30.101:7788; 
  } 
  on pg2 { 
    address 10.0.30.102:7788; 
  } 
} 

2. Allocate the DRBD storage with this command:

drbdadm create-md pg

3. Enable and start the DRBD service:

systemctl enable drbd
systemctl start drbd

4. Use drbdadm on pg1 to invalidate the data on pg2:

drbdadm invalidate-remote pg

5. View the ...