For security reason, we need to keep our server kernel keep updated. Those server has DRBD installed, the DRBD need to rebuild with the updated kernel version. In this tutorial, we will be update one of our cluster hosting, NS82.

Let’s start with secondary server of MySQL server, 183.81.162.6

– SSH to the server
– Verify the drbd role, make sure it is Secondary

[root@ns82-2 ~]# drbdadm status
......
drbd0 role:Secondary
  disk:UpToDate
  ns82-1 role:Primary
    peer-disk:UpToDate
......

– Disconnect the drbd connection

[root@ns82-2 ~]# drbdadm disconnect drbd0

– Stop the drbd service

[root@ns82-2 ~]# systemctl stop drbd

– Update the kernel, kernel-devel and kernel-headers

[root@ns82-2 ~]# yum update kernel kernel-devel kernel-headers

– Reboot the server once the update completed

[root@ns82-2 ~]# init 6

– Once the server up, we need to download the latest version of drbd. During this tutorial written, the latest version is 9.0.16-1

[root@ns82-2 ~]# cd /opt
[root@ns82-2 ~]# wget http://www.linbit.com/downloads/drbd/9.0/drbd-9.0.16-1.tar.gz
[root@ns82-2 ~]# tar xvf drbd-9.0.16-1.tar.gz
[root@ns82-2 ~]# cd drbd-9.0.16
[root@ns82-2 ~]# make 
[root@ns82-2 ~]# make install

– Start the drbd service

[root@ns82-2 ~]# modprobe drbd
[root@ns82-2 ~]# systemctl start drbd

– Verify the status of drbd with

[root@ns82-2 ~]# drbadm status
......
drbd0 role:Secondary
  disk:UpToDate
  ns82-m1 role:Primary
    peer-disk:UpToDate
......