From 5455a00a4bdc95a7906934e5356c3ee5fce23dcc Mon Sep 17 00:00:00 2001 From: Charalampos Kominos <Charalampos.Kominos@enea.com> Date: Mon, 7 May 2018 10:41:57 +0200 Subject: [docs] add info about block storage support Adding volumes in openstack by default uses virtio_blk which limits the amount of disks that can be attached. Here we inform about this shortcoming and supply a workaround. JIRA: ARMBAND-376 Change-Id: I711df5c19befca7a3abfdce9fe9b2b0bb38853ac Signed-off-by: Charalampos Kominos <Charalampos.Kominos@enea.com> --- docs/release/userguide/userguide.rst | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'docs/release/userguide') diff --git a/docs/release/userguide/userguide.rst b/docs/release/userguide/userguide.rst index fd9dfa736..34a797d18 100644 --- a/docs/release/userguide/userguide.rst +++ b/docs/release/userguide/userguide.rst @@ -270,6 +270,37 @@ to make. The images for the above operating systems can be found in their respective websites. + +================= +OpenStack Storage +================= + +OpenStack Cinder is the project behind block storage in OpenStack and Fuel@OPNFV supports LVM out of the box. +By default x86 supports 2 additional block storage devices and ARMBand supports only one. +More devices can be supported if the OS-image created has additional properties allowing block storage devices +to be spawned as SCSI drives. To do this, add the properties below to the server: + + .. code-block:: bash + + openstack image set --property hw_disk_bus='scsi' --property hw_scsi_model='virtio-scsi' <image> + +The choice regarding which bus to use for the storage drives is an important one. Virtio-blk is the default +choice for Fuel@OPNFV which attaches the drives in /dev/vdX. However, since we want to be able to attach a +larger number of volumes to the virtual machines, we recommend the switch to SCSI drives which are attached +in /dev/sdX instead. Virtio-scsi is a little worse in terms of performance but the ability to add a larger +number of drives combined with added features like ZFS, Ceph et al, leads us to suggest the use of virtio-scsi in Fuel@OPNFV for both architectures. + +More details regarding the differences and performance of virtio-blk vs virtio-scsi are beyond the scope +of this manual but can be easily found in other sources online like `4`_ or `5`_. + +.. _4: https://mpolednik.github.io/2017/01/23/virtio-blk-vs-virtio-scsi/ + +.. _5 : https://www.ovirt.org/develop/release-management/features/storage/virtio-scsi/ + +Additional configuration for configuring images in openstack can be found in the OpenStack Glance documentation. + + + =================== Openstack Endpoints =================== @@ -372,3 +403,5 @@ References 1) :ref:`fuel-release-installation-label` 2) `Saltstack Documentation <https://docs.saltstack.com/en/latest/topics>`_ 3) `Saltstack Formulas <http://salt-formulas.readthedocs.io/en/latest/>`_ +4) `Virtio performance <https://mpolednik.github.io/2017/01/23/virtio-blk-vs-virtio-scsi/>`_ +5) `Virtio SCSI <https://www.ovirt.org/develop/release-management/features/storage/virtio-scsi/>`_ -- cgit