Add LVM NVMe support
This patch adds NVMe LVM support to the existing iSCSI LVM configuration
support.
We deprecate the CINDER_ISCSI_HELPER configuration option since we are
no longer limited to iSCSI, and replace it with the CINDER_TARGET_HELPER
option.
The patch also adds another 3 target configuration options:
- CINDER_TARGET_PROTOCOL
- CINDER_TARGET_PREFIX
- CINDER_TARGET_PORT
These options will have different defaults based on the selected target
helper. For tgtadm and lioadm they'll be iSCSI,
iqn.2010-10.org.openstack:, and 3260 respectively, and for nvmet they'll
be nvmet_rdma, nvme-subsystem-1, and 4420.
Besides nvmet_rdma the CINDER_TARGET_PROTOCOL option can also be set to
nvmet_tcp, and nvmet_fc.
For the RDMA transport protocol devstack will be using Soft-RoCE and
creating a device on top of the network interface.
LVM NVMe-TCP support is added in the dependency mentioned in the footer
and LVM NVMe-FC will be added in later patches (need os-brick and cinder
patches) but the code here should still be valid.
Change-Id: I6578cdc27489b34916cdeb72ba3fdf06ea9d4ad8
diff --git a/doc/source/configuration.rst b/doc/source/configuration.rst
index 757b400..0d8773f 100644
--- a/doc/source/configuration.rst
+++ b/doc/source/configuration.rst
@@ -669,6 +669,35 @@
or ``CINDER_QUOTA_SNAPSHOTS`` to the desired value. (The default for
each is 10.)
+DevStack's Cinder LVM configuration module currently supports both iSCSI and
+NVMe connections, and we can choose which one to use with options
+``CINDER_TARGET_HELPER``, ``CINDER_TARGET_PROTOCOL``, ``CINDER_TARGET_PREFIX``,
+and ``CINDER_TARGET_PORT``.
+
+Defaults use iSCSI with the LIO target manager::
+
+ CINDER_TARGET_HELPER="lioadm"
+ CINDER_TARGET_PROTOCOL="iscsi"
+ CINDER_TARGET_PREFIX="iqn.2010-10.org.openstack:"
+ CINDER_TARGET_PORT=3260
+
+Additionally there are 3 supported transport protocols for NVMe,
+``nvmet_rdma``, ``nvmet_tcp``, and ``nvmet_fc``, and when the ``nvmet`` target
+is selected the protocol, prefix, and port defaults will change to more
+sensible defaults for NVMe::
+
+ CINDER_TARGET_HELPER="nvmet"
+ CINDER_TARGET_PROTOCOL="nvmet_rdma"
+ CINDER_TARGET_PREFIX="nvme-subsystem-1"
+ CINDER_TARGET_PORT=4420
+
+When selecting the RDMA transport protocol DevStack will create on Cinder nodes
+a Software RoCE device on top of the ``HOST_IP_IFACE`` and if it is not defined
+then on top of the interface with IP address ``HOST_IP`` or ``HOST_IPV6``.
+
+This Soft-RoCE device will always be created on the Nova compute side since we
+cannot tell beforehand whether there will be an RDMA connection or not.
+
Keystone
~~~~~~~~