OCFS2 on GCP with Multi-Writer Disks

This repository contains code to deploy a two node OCFS2 cluster on Google Cloud using multi-writer persistent disks.

Usage

To deploy the demo:

Create a new Google Cloud project

Open the Cloud Shell for your project and clone the demo repository:

git clone https://github.com/zencore-dev/gcp-pd-multiwriter.git

Change into the terraform code directory:

  cd gcp-pd-multiwriter/terraform

Run Terraform:

terraform init
terraform apply

Access each instance via SSH and run the following commands on both:

# switch to root
sudo -i

# Install the OCFS2 tools and kernel module for the current kernel version:
GCP_KERNEL_VERSION=$(uname -r)
apt install -y ocfs2-tools linux-modules-extra-${GCP_KERNEL_VERSION}

Run the following command in the first instance only, to format the filesystem:

mkfs.ocfs2 -b 4k -C 32K -L "ocfs2" -N 2 /dev/sdb

Run the following commands on both instances:

mkdir /data
dpkg-reconfigure ocfs2-tools

Choose Yes to enable OCFS2 at startup. Accept defaults for the other questions.

Edit /etc/ocfs2/cluster.conf on both VMs and configure the node definitions:

nano /etc/ocfs2/cluster.conf

Add the following to the file:

node:
    ip_port = 7777
    ip_address = 10.0.0.2 
    number = 1
    name = nas-1
    cluster = ocfs2

node:
    ip_port = 7777
    ip_address = 10.0.0.3
    number = 2
    name = nas-2
    cluster = ocfs2

cluster:
    node_count = 2
    name = ocfs2

Finally, register the cluster and mount the shared disk:

o2cb register-cluster ocfs2
mount /dev/sdb /data

You should have a shared filesystem mounted at /data on both instances.

License

This project is licensed under the Apache 2.0 License - see the LICENSE file for details.