Mounting file shares on Ubuntu

Use these instructions to connect a Network File System (NFS) file share to an Ubuntu Linux®-based IBM Cloud® Compute instance.

Before you begin

If your file share was set up with VPC access mode, verify that the virtual server instance where you want to mount the share is in the same zone as the file share. If the file share was set up with Security group access mode, verify that the virtual server instance is part of the same security group. For more information, see Mount target access modes.
Confirm that a mount target for the share exists for the VPC that the instance resides in. If a new mount target is needed, follow the instructions in Creating file shares and mount targets.
Get the mount path of the file share from the mount target. Mount path information can be obtained from the File share details page in the UI, from the CLI, with the API, or Terraform.
If you want to use encryption in transit, you need to obtain an IPsec certificate from the Instance Metadata service. Ensure that encryption in transit is enabled for the mount target. Plus, mount the file share with a secure connection. This feature is only available for file shares with dp2 profiles and security group access mode. For more information, see Encryption in transit - Securing mount connections between file share and host.

Install and run the mount helper utility to mount file shares with encryption in transit or without an encrypted connection.

File Storage for VPC service requires NFS versions v4.1 or higher.

Mounting the file share

Follow these steps to mount a file share on an Ubuntu host. Examples are based on Ubuntu 20.04.

SSH into the Compute instance where you want to mount the file share, then continue with these steps:

Update and upgrade the distribution:
```
apt update && apt upgrade
```
Create a /mnt/nfs directory.
```
mkdir -p /mnt/nfs
```
Install nfs-common:
```
apt install nfs-common
```
Restart your instance:
```
reboot
```

Mount the remote file share:

mount -t nfs4 -o <options> <host:/mount_target> /mnt/nfs

See following example.

mount -t nfs4 -o sec=sys,nfsvers=4.1 fsf-dal2433a-dz.adn.networklayer.com:/nxg_s_voll_mz0726_c391f0ba-50ed-4460-8704-a36032c96a4c /mnt/nfs

Verify that the mount was successful by using the disk file system command df -h:

$ df -h
Filesystem                                                                                    Size  Used Avail Use% Mounted on
/dev/root                                                                                      97G  1.6G   96G   2% /
devtmpfs                                                                                      3.9G     0  3.9G   0% /dev
tmpfs                                                                                         3.9G     0  3.9G   0% /dev/shm
tmpfs                                                                                         798M  508K  797M   1% /run
tmpfs                                                                                         5.0M     0  5.0M   0% /run/lock
tmpfs                                                                                         3.9G     0  3.9G   0% /sys/fs/cgroup
/dev/vda15                                                                                    105M  9.2M   96M   9% /boot/efi
/dev/loop0                                                                                     56M   56M     0 100% /snap/core18/1885
/dev/loop1                                                                                     71M    71M     0 100% /snap/lxd/16922
/dev/loop2                                                                                     31M   31M     0 100% /snap/snapd/9279
tmpfs                                                                                         798M     0  798M   0% /run/user/0
fsf-dal1099a-fz.adn.networklayer.com:/voll_58fd55a_685c_4ccd_b42e_25d5b61129e2   95G  256K   95G   1% /mnt/nfs

Go to the mount point to create a test file and list all files to verify that the share is mounted as read/write.

touch /mnt/nfs/test.txt

ls -al /mnt/nfs

touch /mnt/nfs/test.txt
ls -al /mnt/nfs
total 12
drwxr-xr-x   2 nobody nobody 4096 Apr 28 15:52 .
dr-xr-xr-x. 22 root   root   4096 Apr 28 14:30 ..
-rw-r--r--   1 nobody nobody    0 Apr 28 15:52 test.txt

Make the configuration persistent by editing the file systems table (/etc/fstab). Add the remote share to the list of entries that are automatically mounted on startup:
```
sudo nano /etc/fstab
```
Add a line with the following syntax to the end of the file.
```
(hostname):/(mount_point) /mnt/nfs nfs_version defaults 0 0
```
Example
```
fsf-dal2433a-dz.adn.networklayer.com:/nxg_s_voll_mz0726_c391f0ba-50ed-4460-8704-a36032c96a4c /mnt/nfs nfsvers=4.1 defaults 0 0
```
Verify that the configuration file has no errors.
```
mount -fav
```
If the command completes with no errors, your setup is complete.

For NFS 4.1, add sec=sys to the mount command to prevent file ownership issues. Use _netdev to wait for the storage to be mounted until after all network components are started.

Unmounting the file system

To unmount any currently mounted file system on your host, run the umount command with disk name or mount point name.

umount /dev/sdb

umount /mnt/nfs