27.2 Adding UFS Disks

This section describes how to add a new NVMe Solid-State Drive (SSD) to a computer that currently has only one disk. First, power off the computer and install the disk according to the instructions from the computer, controller, and disk manufacturers. Restart the system and switch to the root user.

Check the /var/run/dmesg.boot file to ensure the new disk has been recognized.

nda1 at nvme0 bus 0 scbus2 target 0 lun 2
nda1: <VMware Virtual NVMe Disk 1.4 VMware NVME_0000>
nda1: Serial Number VMware NVME_0000
nda1: nvme version 1.4
nda1: 10240MB (20971520 512 byte sectors)

...other irrelevant output omitted...

In this example, the newly added 10G NVMe disk appears as nda1.

Creating a Partition Table

This example creates a single partition on the new disk. The GPT partition scheme is preferred over the less flexible MBR scheme.

Note

If the disk to be added is not empty, you can use gpart delete to remove old partition information.

Example 1 Delete partition 1 on disk nda1:

# gpart delete -i 1 nda1

Example 2 Destroy the entire partition table and all partitions on disk nda1:

# gpart destroy -F nda1

Create a GPT partition table for nda1:

# gpart create -s GPT nda1

Creating a Single Partition

Then add a partition. To improve performance on disks with larger hardware block sizes, the partition is aligned to a 1MB boundary:

# gpart add -t freebsd-ufs -a 1M nda1

Tip

The -t option here only writes the partition type GUID; it does not perform actual formatting and is unrelated to the file system being formatted.

You can use gpart show to view disk partition information:

# gpart show -p nda1
=>      40  20971440    nda1  GPT  (10G)
        40      2008          - free -  (1004K)
      2048  20967424  nda1p1  freebsd-ufs  (10G)
  20969472      2008          - free -  (1004K)

The above commands created a GPT partition table and a new 10G disk partition nda1p1 using the UFS file system.

Creating Multiple Partitions

For convenience, multiple partitions can be created.

The following creates 4 partitions on disk nda1 with capacities of 1GB, 2GB, 3GB, and 4GB respectively. Use the -s parameter to specify partition sizes (supports units such as G and M).

• Create the 1st partition: 1G

# gpart add -t freebsd-ufs -a 1M -s 1G nda1

• Create the 2nd partition: 2G

# gpart add -t freebsd-ufs -a 1M -s 2G nda1

• Create the 3rd partition: 3G

# gpart add -t freebsd-ufs -a 1M -s 3G nda1

• Create the 4th partition using all remaining capacity:

# gpart add -t freebsd-ufs -a 1M nda1

You can use gpart show to view disk partition information:

# gpart show -p nda1
=>      40  20971440    nda1  GPT  (10G)
        40      2008          - free -  (1004K)
      2048   2097152  nda1p1  freebsd-ufs  (1.0G)
   2099200   4194304  nda1p2  freebsd-ufs  (2.0G)
   6293504   6291456  nda1p3  freebsd-ufs  (3.0G)
  12584960   8384512  nda1p4  freebsd-ufs  (4.0G)
  20969472      2008          - free -  (1004K)

The above commands created partitions nda1p1, nda1p2, nda1p3, and nda1p4 respectively.

Formatting the File System

Create a file system on the new partition of the new disk:

# newfs -U /dev/nda1p1

Format /dev/nda1p1, /dev/nda1p2, /dev/nda1p3, and /dev/nda1p4 all at once:

# for i in 1 2 3 4; do newfs -U /dev/nda1p$i; done

Mounting the File System

Create an empty directory as a mount point, which is the location in the original disk's file system where the new disk will be mounted:

# mkdir -p /mnt/newdisk

Temporarily mount /dev/nda1p3 to /mnt/newdisk:

# mount /dev/nda1p3 /mnt/newdisk

Perform a write test:

# cd /mnt/newdisk && touch test.txt
/mnt/newdisk # ls -al
total 9
drwxr-xr-x  3 root wheel    512 May 30 17:42 .
drwxr-xr-x  4 root wheel      4 May 30 17:39 ..
drwxrwxr-x  2 root operator 512 May 30 17:32 .snap
-rw-r--r--  1 root wheel      0 May 30 17:42 test.txt

Finally, add an entry in /etc/fstab to automatically mount the new disk at startup:

/dev/nda1p3     /mnt/newdisk    ufs     rw              0       0

You can manually mount the new disk without restarting the system:

# mount /mnt/newdisk

Verify the mount:

Use the mount command to verify (without any arguments)

# mount
/dev/nda1p3 on /mnt/newdisk (ufs, local, soft-updates)

...other output omitted...

You can also use the df command to verify the mount:

# df -hl
/dev/nda1p3           2.9G    8.0K    2.7G     0%    /mnt/newdisk

...other output omitted...

View the contents of the mounted file system:

# ls /mnt/newdisk/
/mnt/newdisk/.snap/    /mnt/newdisk/test.txt