For NetApp's Insight 2023, I did a session demonstrating how to create a truly global namespace utilizing NetApp FlexCache® and Linux autofs. I am providing the steps here for reference.

In this demo, I will be RHEL 9.3. The steps will be similar for different Linux variants. This demo also assumes that this is a fresh setup, and you don't already have autofs configured on your Linux client. If you already have autofs configured, it is up to you not to blow away your current config by following these steps.

Prerequisites

  • Two NFS servers. I'm using NetApp ONTAP and NetApp ONTAP's included feature FlexCache
  • DNS is configured to resolve the hostnames of the two NFS servers
  • nfs-utils package is already installed on client(s)

Environment

  • NFS server 1 mount path: redrock-nas:/flexcache
  • NFS server 2 mount path: colosseum-nas:/flexcache
  • NFS client local NFS mountpoint: /mnt/insight23.lab/demo

Steps

  1. Login to your Linux box with a user who has sudo rights
  2. Install the autofs package: sudo yum install autofs
  3. Add the appropriate entry to /etc/auto.master: sudo echo '/mnt/insight23.lab /etc/auto.nfs' >> /etc/auto.master
  4. Create /etc/auto.nfs and add appropriate entry: sudo echo 'demo -fstype=nfs,rw colosseum-nas,redrock-nas:/flexcache
  5. Enable and start the autofs service: sudo systemctl enable --now autofs
  6. Create the /mnt/insight23.lab folder structure: sudo mkdir -p /mnt/insight23.lab. Notice that I omitted the demo folder creation – autofs will take care of this part
  7. cd into /mnt/insight23.lab/demo: cd /mnt/insight23.lab/demo

When you execute step 7, autofs will detemine which of the two NFS servers, colosseum-nas or redrock-nas in this example, responds the quickest, and will mount that. You can see which server it chose by running mount -t nfs | grep 'insight23.lab'