Configure NFS mounts

Azure CycleCloud provides built-in support for mounting a simple Network File System (NFS). CycleCloud can manage the NFS as a resource, or the NFS can be an external resource.

Default Templates - Network Attached Storage Settings

The default cluster templates for each scheduler include a section for configuring NFS options when creating a cluster.

The /shared/ directory for each cluster is an NFS share by default. The NFS Type dropdown in this configuration section provides options for this NFS share to be either exported from the cluster headnode (the Builtin option), or mounted from an NFS server.

If you select Builtin, you create the NFS share on an Azure Managed Disk (Standard SSD) mounted onto the headnode of the cluster. Use the Size option to specify the size of the provisioned disk.

If you specify the External NFS option, you see extra fields where you can enter the IP address or hostname of the NFS server and other NFS mount options. Use the External NFS option to mount endpoints such as NFS on Azure Files Storage, Azure HPC Cache, Azure NetApp Files, or NFS on Azure Blob Storage.

If you need another NFS mount point, such as a /data resource for all users, select the Add NFS Mount option. You see extra fields where you can add another mount.

Mount an NFS filesystem

To mount an existing NFS filesystem, use the following code:

[[[configuration cyclecloud.mounts.nfs_data]]]
type = nfs
mountpoint = /mnt/exports/nfs_data
export_path = /mnt/exports/data

The export_path is the path on the server. The mountpoint is the path where you mount the share on the client. You can export the mounted NFS filesystem from a node in the same CycleCloud cluster, a node in another CycleCloud cluster, or a separate NFS filesystem that allows simple mounts. If a node in the local cluster exports the filesystem, CycleCloud uses search to discover the address automatically. If a node in a different CycleCloud cluster exports the filesystem, you can specify the cluster_name attribute in the mount configuration to instruct CycleCloud to search the cluster with that name:

[[[configuration cyclecloud.mounts.other_cluster_fs]]]
type = nfs
mountpoint = /mnt/exports/other_cluster_fs
export_path = /mnt/exports/data
cluster_name = filesystem_cluster

To specify the location of the filesystem explicitly (required for mounting non-CycleCloud filesystems), add the address attribute with the hostname or IP of the filesystem in the mount configuration:

[[[configuration cyclecloud.mounts.external_filer]]]
type = nfs
mountpoint = /mnt/exports/external_filer
address = 54.83.20.2

Default shares

By default, most CycleCloud cluster types include at least one shared drive mounted at /shared and /mnt/exports/shared. For clusters that need a simple shared filesystem, this mount is often sufficient.

Many cluster types also include a second NFS mount at /sched and /mnt/exports/sched which is reserved for use by the chosen scheduler. In general, applications shouldn't access this mount.

The mount configurations for the default shares reserve filesystem names cyclecloud.mounts.shared and cyclecloud.mounts.sched. You can modify the default configurations for these shares, but changing them might cause unexpected behavior because many cluster types rely on the default mounts.

Disabling NFS mounts

You can disable Azure CycleCloud NFS mounts by setting the disabled attribute to true. You can also disable the default shares this way:

[[[configuration]]]
    cyclecloud.mounts.sched.disabled = true
    cyclecloud.mounts.shared.disabled = true
    cshared.server.legacy_links_disabled = true

Many clusters assume a shared storage device is available cluster-wide at /shared. If you use these configurations, enable a file server and mount it on each cluster node with:

[[[configuration cyclecloud.mounts.external_shared]]]
    type = nfs
    mountpoint = /shared
    export_path = /mnt/raid/export
    address = 54.83.20.2

Mount an Azure Managed Lustre Filesystem

Azure CycleCloud clusters have built-in support for mounting Azure Managed Lustre.

To create a new Azure Managed Lustre Filesystem (AMLFS) for use in your cluster, see the AMLFS documentation.

To mount an existing AMLFS:

[[[configuration cyclecloud.mounts.lustre_data]]]
type = lustre
address = 10.4.0.14
mountpoint = /lustre_data

The required address attribute specifies the hostname or IP of the AMLFS. The required mountpoint attribute specifies the path to mount the AMLFS on the cluster nodes.

Optionally, use the export_path attribute to mount existing subdirectories within the AMLFS. For a newly created AMLFS, the only existing path is /. If you don't set export_path, it defaults to tcp:/lustrefs/ (AMLFS mount points must be prefixed with tcp:/lustrefs).

For example, if you create the /data path in your Lustre filesystem, you can mount data as follows:

[[[configuration cyclecloud.mounts.lustre_data]]]
type = lustre
address = 10.4.0.14
mountpoint = /lustre_data
export_path = tcp:/lustrefs/data/
options = noatime, flock

Use the optional options attribute to add mount options for an AMLFS mount. If you don't specify options, it defaults to noatime, flock.

[!NOTE] Lustre performs best if nodes unmount the filesystem before shutting down. We strongly recommend that you enable Termination Notifications for nodes that mount an AMLFS filesystem. CycleCloud registers a shutdown script that cleanly unmounts the filesystem when a node terminates. The script runs if you enable Termination Notifications.

Mount configuration options

Option	Definition
type	REQUIRED Set the type attribute to nfs for NFS mounts or lustre for AMLFS mounts. This setting differentiates these mounts from volume mounts and other shared filesystem types.
export_path	Set the location of the export on the remote filesystem. The export_path must already exist on the remote filesystem. If you don't specify an export_path, the mountpoint of the mount is used as the export_path.
mountpoint	Set the location where the filesystem is mounted after applying any additional configuration. If the directory doesn't already exist, it's created.
cluster_name	Set the name of the CycleCloud cluster that exports the filesystem. If you don't set this option, the node's local cluster is assumed.
address	The explicit hostname or IP address of the filesystem. If you don't set this value, the search process tries to find the filesystem in a CycleCloud cluster.
options	Any non-default options to use when mounting the filesystem.
disabled	If set to true, the node doesn't mount the filesystem.

Note

Most schedulers don't support changing the hostname scheme.

Further Reading

• How to Mount a Disk
• How to Create a File Share and File Server