Serveur avec baies de disques, simple attachement
=================================================

.. meta::
    :authors: Loïs Taulelle

Ceci est un exemple de configuration comprenant un serveur et trois baies de disques. Terminologie : :term:`NAS` + :term:`DAS`.

matériel :
----------

* Serveur :
    * Dell R740 (de l'année 2020),
    * 2x Intel Xéon Silver 4214R CPU @ 2.40GHz, 2 threads par coeur, soit 48 coeurs logiques,
    * 192 GiB de :term:`RAM`,
    * Carte :term:`BOSS` 250 GiB pour l':term:`OS`, Debian 11 Bullseye,
    * 2x 10Gib/s Ethernet Controller,
    * 8x emplacements 2,5\" :term:`SAS` libres,
    * 1x contrôleur :term:`HBA` externe.
* Baie(s)
    * 3x chassis MD1200,
    * 1x :term:`EMM` par chassis,
    * 12x disques 16 TiB :term:`SAS` par chassis.


configuration :
---------------

Cette disposition est la plus simple (avec une ou plusieurs baies) et ne nécessite aucune configuration particulière. Un fichier *vdev_id.conf* avec la liste des disques et c'est tout.

.. figure:: /_static/simple-chain.png
    :alt: DAS, simple, illustration Dell
    :align: center

    :term:`DAS`, simple attachement (illustration Dell)


- fichier ``/etc/modprobe.d/zfs.conf`` :

.. code-block:: bash

    options spl spl_kmem_cache_slab_limit=16384
    # ARC entre 96GiB et 144GiB
    options zfs zfs_arc_min=103079215104 zfs_arc_max=154618822656


- fichier ``/etc/zfs/vdev_id.conf`` :

.. code-block:: bash

    # baie 1
    alias B1D0 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy0-lun-0
    alias B1D1 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy1-lun-0
    alias B1D2 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy2-lun-0
    alias B1D3 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy3-lun-0
    alias B1D4 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy4-lun-0
    alias B1D5 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy5-lun-0
    alias B1D6 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy6-lun-0
    alias B1D7 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy7-lun-0
    alias B1D8 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy8-lun-0
    alias B1D9 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy9-lun-0
    alias B1D10 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy10-lun-0
    alias B1D11 pci-0000:60:00.0-sas-exp0x520474729a92cfff-phy11-lun-0
    # baie 2
    alias B2D0 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy0-lun-0
    alias B2D1 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy1-lun-0
    alias B2D2 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy2-lun-0
    alias B2D3 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy3-lun-0
    alias B2D4 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy4-lun-0
    alias B2D5 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy5-lun-0
    alias B2D6 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy6-lun-0
    alias B2D7 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy7-lun-0
    alias B2D8 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy8-lun-0
    alias B2D9 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy9-lun-0
    alias B2D10 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy10-lun-0
    alias B2D11 pci-0000:60:00.0-sas-exp0x520474729a9dbbff-phy11-lun-0
    # baie 3
    alias B3D0 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy0-lun-0
    alias B3D1 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy1-lun-0
    alias B3D2 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy2-lun-0
    alias B3D3 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy3-lun-0
    alias B3D4 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy4-lun-0
    alias B3D5 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy5-lun-0
    alias B3D6 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy6-lun-0
    alias B3D7 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy7-lun-0
    alias B3D8 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy8-lun-0
    alias B3D9 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy9-lun-0
    alias B3D10 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy10-lun-0
    alias B3D11 pci-0000:60:00.0-sas-exp0x500c04f210023cbf-phy11-lun-0


- commande ``zpool create`` :

.. code-block:: bash

    zpool create -f data \
    raidz2 B1D0 B1D1 B1D2 B1B3 B1D4 B1D5 \
    raidz2 B1D6 B1D7 B1D8 B1D9 B1D10 B1D11 \
    raidz2 B2D0 B2D1 B2D2 B2B3 B2D4 B2D5 \
    raidz2 B2D6 B2D7 B2D8 B2D9 B2D10 B2D11 \
    raidz2 B3D0 B3D1 B3D2 B3B3 B3D4 B3D5 \
    raidz2 B3D6 B3D7 B3D8 B3D9 B3D10 B3D11 \
    
    zfs set atime=off data
    zfs set compression=on data


- commande ``zpool status`` :

.. code-block:: bash

    zpool status
      pool: data
    state: ONLINE
      scan: scrub repaired 0 in 15h30m with 0 errors on Wed Dec  1 03:01:08 2021
    config:

        NAME        STATE     READ WRITE CKSUM
        data        ONLINE       0     0     0
          raidz2-0  ONLINE       0     0     0
            B1D0    ONLINE       0     0     0
            B1D1    ONLINE       0     0     0
            B1D2    ONLINE       0     0     0
            B1D3    ONLINE       0     0     0
            B1D4    ONLINE       0     0     0
            B1D5    ONLINE       0     0     0
          raidz2-1  ONLINE       0     0     0
            B1D6    ONLINE       0     0     0
            B1D7    ONLINE       0     0     0
        [ ... ]
          raidz2-5  ONLINE       0     0     0
            B3D6    ONLINE       0     0     0
            B3D7    ONLINE       0     0     0
            B3D8    ONLINE       0     0     0
            B3D9    ONLINE       0     0     0
            B3D10   ONLINE       0     0     0
            B3D11   ONLINE       0     0     0

    errors: No known data errors


.. todo:: avantages, inconvénients

-> en cas de problème sur la frontale, elle est peut être échangé sans "perdre" la baie.

zpool import, restauration des paramètres du partage NFS, fini.