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--- nas:build_a_linux_nas:prepare_the_raid_disks [2021/09/25 15:49] – created peter
+++ nas:build_a_linux_nas:prepare_the_raid_disks [2021/10/12 20:36] (current) – [Test the Disks] peter
@@ Line 1: / Line 1: @@
 ====== NAS - Build a Linux NAS - Prepare the RAID Disks ======
+===== Determine the available disks =====
+<code bash>
+lsblk
+</code>
+returns:
+<code bash>
+NAME                   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
+sda                      8:0    0 232.9G  0 disk
+├─sda1                   8:1    0  1007K  0 part
+├─sda2                   8:2    0   512M  0 part /boot/efi
+├─sda3                 253:28   0     8G  0 part [SWAP]
+├─sda4                 253:29   0    58G  0 part /
+sdb                      8:32   0  14.6T  0 disk
+sdc                      8:48   0  14.6T  0 disk
+sdd                      8:64   0  14.6T  0 disk
+</code>
+<WRAP info>
+**NOTE:**  This shows:
+  * **sda**:  The boot disk of the host OS. Leave this alone!
+  * **sdb**:  A free disk.
+  * **sdc**:  A free disk.
+  * **sdd**:  A free disk.
+The free disks do not have any partitions yet and will be included into a RAID.
+</WRAP>
+----
+===== Obtain the Serial Numbers of the Disks =====
+<code bash>
+hdparm -i /dev/sdd | grep SerialNo
+</code>
+returns:
+<code bash>
+Model=ST16000NM001G-2KK103, FwRev=SB30, SerialNo=WL2091XL
+</code>
+<WRAP important>
+**IMPORTANT:**  Obtain the serial number for every disk; and keep a record of this somewhere safe.
+</WRAP>
+<WRAP info>
+**NOTE:**  Many disks also have the serial number written on the disk.
+The reason for recording the serial number of each disk is that in the case of a disk failure, there needs to be a way to determine which disk has failed and needs to be replaced.
+  * The enclosure being used for the disks may not support hot-swapping and there may not be a separate light for each disk, so there may not be a straight-forward way to determine which specific disk has failed.
+</WRAP>
+----
+===== Test the Disks =====
+All hard drives, both new and old, should be tested before adding them to an array.
+See S.M.A.R.T. to view smart data and run smart tests.
+Do a short smart test:
+<code bash>
+smartctl -t short /dev/sdb [-d sat]
+</code>
+Do a long smart test:
+<code bash>
+smartctl -t long /dev/sdb [-d sat]
+</code>
+Check all smart attributes:
+<code bash>
+smartctl -a /dev/sdb [-d sat]
+</code>
+Do a random readwrite test:
+<code bash>
+sudo fio --filename="/dev/sdb --name=randwrite --ioengine=sync --iodepth=1 --rw=randrw --rwmixread=50 --rwmixwrite=50 --bs=4k --direct=0 --numjobs=8 --size=300G --runtime=7200 --group_reporting
+</code>
+<WRAP info>
+**NOTE:** The smartmontools package might be needed to be installed:
+<code bash>
+sudo apt install smartmontools
+</code>
+  * **-d sat**:  Sata disks.
+See:  https://www.smartmontools.org/
+</WRAP>
+----
+===== Initialize the free disks =====
+<code bash>
+sudo fdisk /dev/sdb
+</code>
+returns:
+<code bash>
+Welcome to fdisk (util-linux 2.36.1).
+Changes will remain in memory only, until you decide to write them.
+Be careful before using the write command.
+Device does not contain a recognized partition table.
+The size of this disk is 14.6 TiB (16000900661248 bytes). DOS partition table format cannot be used on drives for volumes larger than 2199023255040 bytes for 512-byte sectors. Use GUID partition table format (GPT).
+Created a new DOS disklabel with disk identifier 0xc778227a.
+Command (m for help):
+</code>
+----
+==== Create a GPT Partition ====
+<code bash>
+Command (m for help): g
+</code>
+returns:
+<code bash>
+Created a new GPT disklabel (GUID: 6D811672-A5FE-BA4F-8F79-D17E0285C5E1).
+</code>
+<WRAP info>
+**NOTE:**  GPT (GUID Partition Table) is much better than MBR (Master Boot Record) partitions:
+  * GPT supports much larger disks.
+  * GPT allows for a nearly unlimited number of partitions.
+  * GPT also stores cyclic redundancy check (CRC) values to check that its data is intact.
+    * If the data is corrupted, GPT can notice the problem and attempt to recover the damaged data from another location on the disk.
+</WRAP>
+----
+==== Create a Linux RAID Partition ====
+<code bash>
+Command (m for help): n
+Partition number (1-128, default 1):
+First sector (2048-31251759070, default 2048):
+Last sector, +/-sectors or +/-size{K,M,G,T,P} (2048-31251759070, default 31251759070):
+</code>
+returns:
+<code bash>
+Created a new partition 1 of type 'Linux filesystem' and of size 14.6 TiB.
+</code>
+<WRAP info>
+**NOTE:** Just taking the default values uses the entire disk.
+</WRAP>
+----
+==== Print the Partition ====
+<code bash>
+Command (m for help): p
+</code>
+returns:
+<code bash>
+Disk /dev/sdb: 14.55 TiB, 16000900661248 bytes, 31251759104 sectors
+Disk model: ST16000NM001G-2K
+Units: sectors of 1 * 512 = 512 bytes
+Sector size (logical/physical): 512 bytes / 4096 bytes
+I/O size (minimum/optimal): 4096 bytes / 4096 bytes
+Disklabel type: gpt
+Disk identifier: 6D811672-A5FE-BA4F-8F79-D17E0285C5E1
+Device     Start         End     Sectors  Size Type
+/dev/sdb1   2048 31251759070 31251757023 14.6T Linux filesystem
+</code>
+<WRAP info>
+**NOTE:** This shows that there is a single partition, /dev/sdb1, using the entire disk.
+</WRAP>
+----
+==== Change the Partition Type ====
+<code bash>
+Command (m for help): t
+Selected partition 1
+Partition type or alias (type L to list all): 29
+</code>
+returns:
+<code bash>
+Changed type of partition 'Linux filesystem' to 'Linux RAID'.
+</code>
+<WRAP info>
+**NOTE:** The type is changed to Linux RAID, which is type 29.
+</WRAP>
+----
+==== Print the Partition again ====
+<code bash>
+Command (m for help): p
+</code>
+returns:
+<code bash>
+Disk /dev/sdd: 14.55 TiB, 16000900661248 bytes, 31251759104 sectors
+Disk model: ST16000NM001G-2K
+Units: sectors of 1 * 512 = 512 bytes
+Sector size (logical/physical): 512 bytes / 4096 bytes
+I/O size (minimum/optimal): 4096 bytes / 4096 bytes
+Disklabel type: gpt
+Disk identifier: EAA2F832-9810-AA45-9DDB-8ED531C20139
+Device     Start         End     Sectors  Size Type
+/dev/sdd1   2048 31251759070 31251757023 14.6T Linux RAID
+</code>
+<WRAP info>
+**NOTE:** This shows the Type has been changed to **Linux RAID**.
+</WRAP>
+----
+==== Write the Partition Table ====
+<code bash>
+Command (m for help): w
+</code>
+returns:
+<code bash>
+The partition table has been altered.
+Calling ioctl() to re-read partition table.
+Syncing disks.</code>
+----
+===== Partition other Disks =====
+<WRAP info>
+**NOTE:** Repeat the above instructions for the other free disks.
+</WRAP>
+----
+===== Check the available disks again =====
+<code bash>
+lsblk
+</code>
+returns:
+<code bash>
+NAME                   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
+sda                      8:0    0 232.9G  0 disk
+├─sda1                   8:1    0  1007K  0 part
+├─sda2                   8:2    0   512M  0 part /boot/efi
+├─sda3                 253:28   0     8G  0 part [SWAP]
+├─sda4                 253:29   0    58G  0 part /
+sdb                      8:32   0  14.6T  0 disk
+├─sdb1                   8:33   0  14.6T  0 part
+sdc                      8:48   0  14.6T  0 disk
+├─sdc1                   8:49   0  14.6T  0 part
+sdd                      8:64   0  14.6T  0 disk
+├─sdd1                   8:65   0  14.6T  0 part
+</code>
+<WRAP info>
+**NOTE:**  This shows the original free disks all now have partitions.
+  * At this point, these disks can be tied together as a RAID array.
+</WRAP>