openstack/ironic
Code Issues Proposed changes

Software RAID: Add documentation

Browse Source 
Update the RAID documentation in the admin guide with the IPA
support for Software RAID.

Change-Id: I3383e4b4b3c5a887e6795043ad8126d4d4a216d2
Story: #2004581
Task: #33643
This commit is contained in:
Arne Wiebalck 2019-06-21 17:16:43 +02:00
parent 46533ebea2
commit 2f5ac84211
1 changed files with 59 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

69
doc/source/admin/raid.rst
View File

@ -30,11 +30,16 @@ command ``openstack baremetal node validate <node-uuid>``.
Build agent ramdisk which supports RAID configuration
=====================================================
For doing in-band RAID configuration, Ironic needs an agent ramdisk bundled
with a hardware manager which supports RAID configuration for your hardware.
For example, the :ref:`DIB_raid_support` should be used for HPE
For doing in-band hardware RAID configuration, Ironic needs an agent ramdisk
bundled with a hardware manager which supports RAID configuration for your
hardware. For example, the :ref:`DIB_raid_support` should be used for HPE
Proliant Servers.
.. note::
For in-band software RAID, the agent ramdisk does not need to be bundled
with a hardware manager as the generic hardware manager in the Ironic
Python Agent already provides (basic) support for software RAID.
RAID configuration JSON format
==============================
The desired RAID configuration and current RAID configuration are represented
@ -134,6 +139,8 @@ The RAID properties can be split into 4 different types:
The values for these properties are hardware dependent.
- ``controller`` - The name of the controller as read by the RAID interface.
In order to trigger the setup of a Software RAID via the Ironic Python
Agent, the value of this property needs to be set to "software".
- ``physical_disks`` - A list of physical disks to use as read by the
RAID interface.
@ -144,6 +151,11 @@ The RAID properties can be split into 4 different types:
will fail (because the appropriate backing physical disks could
not be found).
.. note::
For software RAID as provided by the generic hardware manager that ships
with the Ironic Python Agent, only the mandatory properties (plus the
required ``controller`` property) are currently supported.
Examples for ``target_raid_config``
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@ -224,6 +236,22 @@ HDD::
]
}
*Example 5*. Software RAID with two RAID devices::
{
"logical_disks": [
{
"size_gb": 100,
"raid_level": "1",
"controller": "software"
},
{
"size_gb": "MAX",
"raid_level": "0",
"controller": "software"
}
]
}
Current RAID configuration
--------------------------
@ -243,7 +271,8 @@ Workflow
========
* Operator configures the bare metal node with a hardware type that has
a ``RAIDInterface`` other than ``no-raid``.
a ``RAIDInterface`` other than ``no-raid``. For instance, for Software RAID,
this would be ``agent``.
* For in-band RAID configuration, operator builds an agent ramdisk which
supports RAID configuration by bundling the hardware manager with the
@ -254,11 +283,11 @@ Workflow
`Target RAID configuration`_. The target RAID configuration is set on
the Ironic node::
openstack baremetal --os-baremetal-api-version 1.15 node set <node-uuid-or-name> \
openstack baremetal node set <node-uuid-or-name> \
--target-raid-config <JSON file containing target RAID configuration>
The CLI command can accept the input from standard input also:
openstack baremetal --os-baremetal-api-version 1.15 node set <node-uuid-or-name> \
openstack baremetal node set <node-uuid-or-name> \
--target-raid-config -
* Create a JSON file with the RAID clean steps for manual cleaning. Add other
@ -283,13 +312,33 @@ Workflow
* Bring the node to ``manageable`` state and do a ``clean`` action to start
cleaning on the node::
openstack baremetal --os-baremetal-api-version 1.15 node clean <node-uuid-or-name> \
openstack baremetal node clean <node-uuid-or-name> \
--clean-steps <JSON file containing clean steps created above>
* After manual cleaning is complete, the current RAID configuration can be
viewed using::
* After manual cleaning is complete, the current RAID configuration is
reported in the ``raid_config`` field when running::
openstack baremetal --os-baremetal-api-version 1.15 node show <node-uuid-or-name>
openstack baremetal node show <node-uuid-or-name>
Current Limitations of Software RAID
====================================
There are certain limitations to be aware of when setting up a Software RAID via the
Ironic Python Agent:
* There is no way to select the disks which are used to set up the software RAID,
so the Ironic Python Agent will use all available disks. This seems appropriate
for servers with 2 or 4 disks, but needs to be considered when disk arrays are
attached.
* The number of created Software RAID devices must be 1 or 2. If there is only one
Software RAID device, it has to be a RAID-1. If there are two, the first one has
to be a RAID-1, while the RAID level for the second one can 0, 1, or 1+0. As the
first RAID device will be the deployment device, enforcing a RAID-1 reduces the
risk of ending up with a non-booting node in case of a disk failure.
* There is no support for partition images, only whole-disk images are supported with
Software RAID.
Using RAID in nova flavor for scheduling
========================================