Merge pull request #18989 from ceph/wip-luminous-rm22154

luminous: ceph-disk create deprecation warnings

Reviewed-by: Andrew Schoen <aschoen@redhat.com>

doc/ceph-volume/index.rst

@@ -17,6 +17,33 @@ that may have been deployed with ``ceph-disk``.
 * :ref:`ceph-volume-lvm`
 * :ref:`ceph-volume-simple`
 
+
+Migrating
+---------
+Starting on Ceph version 12.2.2, ``ceph-disk`` is deprecated. Deprecation
+warnings will show up that will link to this page. It is strongly suggested
+that users start consuming ``ceph-volume``.
+
+New deployments
+^^^^^^^^^^^^^^^
+For new deployments, :ref:`ceph-volume-lvm` is recommended, it can use any
+logical volume as input for data OSDs, or it can setup a minimal/naive logical
+volume from a device.
+
+Existing OSDs
+^^^^^^^^^^^^^
+If the cluster has OSDs that were provisioned with ``ceph-disk``, then
+``ceph-volume`` can take over the management of these with
+:ref:`ceph-volume-simple`. A scan is done on the data device or OSD directory,
+and ``ceph-disk`` is fully disabled.
+
+Encrypted OSDs
+^^^^^^^^^^^^^^
+If using encryption with OSDs, there is currently no support in ``ceph-volume``
+for this scenario (although support for this is coming soon). In this case, it
+is OK to continue to use ``ceph-disk`` until ``ceph-volume`` fully supports it.
+This page will be updated when that happens.
+
 .. toctree::
    :hidden:
    :maxdepth: 3

src/ceph-disk/ceph_disk/main.py

@@ -42,12 +42,23 @@
 import grp
 import textwrap
 import glob
+import warnings
 
 CEPH_OSD_ONDISK_MAGIC = 'ceph osd volume v026'
 CEPH_LOCKBOX_ONDISK_MAGIC = 'ceph lockbox volume v001'
 
 KEY_MANAGEMENT_MODE_V1 = 'ceph-mon v1'
 
+DEPRECATION_WARNING = """
+*******************************************************************************
+This tool is now deprecated in favor of ceph-volume.
+It is recommended to use ceph-volume for OSD deployments. For details see:
+
+    http://docs.ceph.com/docs/master/ceph-volume/#migrating
+
+*******************************************************************************
+"""
+
 PTYPE = {
     'regular': {
         'journal': {
@@ -5638,6 +5649,8 @@ def make_zap_parser(subparsers):
 
 
 def main(argv):
+    # Deprecate from the very beginning
+    warnings.warn(DEPRECATION_WARNING)
     args = parse_args(argv)
 
     setup_logging(args.verbose, args.log_stdout)
@@ -5657,10 +5670,20 @@ def main(argv):
     CEPH_PREF_GROUP = args.setgroup
 
     if args.verbose:
-        args.func(args)
+        try:
+            args.func(args)
+        except Exception:
+            # warn on any exception when running with verbosity
+            warnings.warn(DEPRECATION_WARNING)
+            # but still raise the original issue
+            raise
+
     else:
         main_catch(args.func, args)
 
+    # if there aren't any errors, still log again at the very bottom
+    warnings.warn(DEPRECATION_WARNING)
+
 
 def setup_logging(verbose, log_stdout):
     loglevel = logging.WARNING
@@ -5687,6 +5710,8 @@ def main_catch(func, args):
         func(args)
 
     except Error as e:
+        # warn on generic 'error' exceptions
+        warnings.warn(DEPRECATION_WARNING)
         raise SystemExit(
             '{prog}: {msg}'.format(
                 prog=args.prog,
@@ -5695,6 +5720,8 @@ def main_catch(func, args):
         )
 
     except CephDiskException as error:
+        # warn on ceph-disk exceptions
+        warnings.warn(DEPRECATION_WARNING)
         exc_name = error.__class__.__name__
         raise SystemExit(
             '{prog} {exc_name}: {msg}'.format(