charm-cinder-ceph/hooks/charmhelpers/contrib/storage/linux/ceph.py

384 lines
11 KiB
Python

#
# Copyright 2012 Canonical Ltd.
#
# This file is sourced from lp:openstack-charm-helpers
#
# Authors:
# James Page <james.page@ubuntu.com>
# Adam Gandelman <adamg@ubuntu.com>
#
import os
import shutil
import json
import time
from subprocess import (
check_call,
check_output,
CalledProcessError
)
from charmhelpers.core.hookenv import (
relation_get,
relation_ids,
related_units,
log,
INFO,
WARNING,
ERROR
)
from charmhelpers.core.host import (
mount,
mounts,
service_start,
service_stop,
service_running,
umount,
)
from charmhelpers.fetch import (
apt_install,
)
KEYRING = '/etc/ceph/ceph.client.{}.keyring'
KEYFILE = '/etc/ceph/ceph.client.{}.key'
CEPH_CONF = """[global]
auth supported = {auth}
keyring = {keyring}
mon host = {mon_hosts}
"""
def install():
''' Basic Ceph client installation '''
ceph_dir = "/etc/ceph"
if not os.path.exists(ceph_dir):
os.mkdir(ceph_dir)
apt_install('ceph-common', fatal=True)
def rbd_exists(service, pool, rbd_img):
''' Check to see if a RADOS block device exists '''
try:
out = check_output(['rbd', 'list', '--id', service,
'--pool', pool])
except CalledProcessError:
return False
else:
return rbd_img in out
def create_rbd_image(service, pool, image, sizemb):
''' Create a new RADOS block device '''
cmd = [
'rbd',
'create',
image,
'--size',
str(sizemb),
'--id',
service,
'--pool',
pool
]
check_call(cmd)
def pool_exists(service, name):
''' Check to see if a RADOS pool already exists '''
try:
out = check_output(['rados', '--id', service, 'lspools'])
except CalledProcessError:
return False
else:
return name in out
def get_osds(service):
'''
Return a list of all Ceph Object Storage Daemons
currently in the cluster
'''
version = ceph_version()
if version and version >= '0.56':
return json.loads(check_output(['ceph', '--id', service,
'osd', 'ls', '--format=json']))
else:
return None
def create_pool(service, name, replicas=2):
''' Create a new RADOS pool '''
if pool_exists(service, name):
log("Ceph pool {} already exists, skipping creation".format(name),
level=WARNING)
return
# Calculate the number of placement groups based
# on upstream recommended best practices.
osds = get_osds(service)
if osds:
pgnum = (len(osds) * 100 / replicas)
else:
# NOTE(james-page): Default to 200 for older ceph versions
# which don't support OSD query from cli
pgnum = 200
cmd = [
'ceph', '--id', service,
'osd', 'pool', 'create',
name, str(pgnum)
]
check_call(cmd)
cmd = [
'ceph', '--id', service,
'osd', 'pool', 'set', name,
'size', str(replicas)
]
check_call(cmd)
def delete_pool(service, name):
''' Delete a RADOS pool from ceph '''
cmd = [
'ceph', '--id', service,
'osd', 'pool', 'delete',
name, '--yes-i-really-really-mean-it'
]
check_call(cmd)
def _keyfile_path(service):
return KEYFILE.format(service)
def _keyring_path(service):
return KEYRING.format(service)
def create_keyring(service, key):
''' Create a new Ceph keyring containing key'''
keyring = _keyring_path(service)
if os.path.exists(keyring):
log('ceph: Keyring exists at %s.' % keyring, level=WARNING)
return
cmd = [
'ceph-authtool',
keyring,
'--create-keyring',
'--name=client.{}'.format(service),
'--add-key={}'.format(key)
]
check_call(cmd)
log('ceph: Created new ring at %s.' % keyring, level=INFO)
def create_key_file(service, key):
''' Create a file containing key '''
keyfile = _keyfile_path(service)
if os.path.exists(keyfile):
log('ceph: Keyfile exists at %s.' % keyfile, level=WARNING)
return
with open(keyfile, 'w') as fd:
fd.write(key)
log('ceph: Created new keyfile at %s.' % keyfile, level=INFO)
def get_ceph_nodes():
''' Query named relation 'ceph' to detemine current nodes '''
hosts = []
for r_id in relation_ids('ceph'):
for unit in related_units(r_id):
hosts.append(relation_get('private-address', unit=unit, rid=r_id))
return hosts
def configure(service, key, auth):
''' Perform basic configuration of Ceph '''
create_keyring(service, key)
create_key_file(service, key)
hosts = get_ceph_nodes()
with open('/etc/ceph/ceph.conf', 'w') as ceph_conf:
ceph_conf.write(CEPH_CONF.format(auth=auth,
keyring=_keyring_path(service),
mon_hosts=",".join(map(str, hosts))))
modprobe('rbd')
def image_mapped(name):
''' Determine whether a RADOS block device is mapped locally '''
try:
out = check_output(['rbd', 'showmapped'])
except CalledProcessError:
return False
else:
return name in out
def map_block_storage(service, pool, image):
''' Map a RADOS block device for local use '''
cmd = [
'rbd',
'map',
'{}/{}'.format(pool, image),
'--user',
service,
'--secret',
_keyfile_path(service),
]
check_call(cmd)
def filesystem_mounted(fs):
''' Determine whether a filesytems is already mounted '''
return fs in [f for f, m in mounts()]
def make_filesystem(blk_device, fstype='ext4', timeout=10):
''' Make a new filesystem on the specified block device '''
count = 0
e_noent = os.errno.ENOENT
while not os.path.exists(blk_device):
if count >= timeout:
log('ceph: gave up waiting on block device %s' % blk_device,
level=ERROR)
raise IOError(e_noent, os.strerror(e_noent), blk_device)
log('ceph: waiting for block device %s to appear' % blk_device,
level=INFO)
count += 1
time.sleep(1)
else:
log('ceph: Formatting block device %s as filesystem %s.' %
(blk_device, fstype), level=INFO)
check_call(['mkfs', '-t', fstype, blk_device])
def place_data_on_block_device(blk_device, data_src_dst):
''' Migrate data in data_src_dst to blk_device and then remount '''
# mount block device into /mnt
mount(blk_device, '/mnt')
# copy data to /mnt
copy_files(data_src_dst, '/mnt')
# umount block device
umount('/mnt')
# Grab user/group ID's from original source
_dir = os.stat(data_src_dst)
uid = _dir.st_uid
gid = _dir.st_gid
# re-mount where the data should originally be
# TODO: persist is currently a NO-OP in core.host
mount(blk_device, data_src_dst, persist=True)
# ensure original ownership of new mount.
os.chown(data_src_dst, uid, gid)
# TODO: re-use
def modprobe(module):
''' Load a kernel module and configure for auto-load on reboot '''
log('ceph: Loading kernel module', level=INFO)
cmd = ['modprobe', module]
check_call(cmd)
with open('/etc/modules', 'r+') as modules:
if module not in modules.read():
modules.write(module)
def copy_files(src, dst, symlinks=False, ignore=None):
''' Copy files from src to dst '''
for item in os.listdir(src):
s = os.path.join(src, item)
d = os.path.join(dst, item)
if os.path.isdir(s):
shutil.copytree(s, d, symlinks, ignore)
else:
shutil.copy2(s, d)
def ensure_ceph_storage(service, pool, rbd_img, sizemb, mount_point,
blk_device, fstype, system_services=[]):
"""
NOTE: This function must only be called from a single service unit for
the same rbd_img otherwise data loss will occur.
Ensures given pool and RBD image exists, is mapped to a block device,
and the device is formatted and mounted at the given mount_point.
If formatting a device for the first time, data existing at mount_point
will be migrated to the RBD device before being re-mounted.
All services listed in system_services will be stopped prior to data
migration and restarted when complete.
"""
# Ensure pool, RBD image, RBD mappings are in place.
if not pool_exists(service, pool):
log('ceph: Creating new pool {}.'.format(pool))
create_pool(service, pool)
if not rbd_exists(service, pool, rbd_img):
log('ceph: Creating RBD image ({}).'.format(rbd_img))
create_rbd_image(service, pool, rbd_img, sizemb)
if not image_mapped(rbd_img):
log('ceph: Mapping RBD Image {} as a Block Device.'.format(rbd_img))
map_block_storage(service, pool, rbd_img)
# make file system
# TODO: What happens if for whatever reason this is run again and
# the data is already in the rbd device and/or is mounted??
# When it is mounted already, it will fail to make the fs
# XXX: This is really sketchy! Need to at least add an fstab entry
# otherwise this hook will blow away existing data if its executed
# after a reboot.
if not filesystem_mounted(mount_point):
make_filesystem(blk_device, fstype)
for svc in system_services:
if service_running(svc):
log('ceph: Stopping services {} prior to migrating data.'
.format(svc))
service_stop(svc)
place_data_on_block_device(blk_device, mount_point)
for svc in system_services:
log('ceph: Starting service {} after migrating data.'
.format(svc))
service_start(svc)
def ensure_ceph_keyring(service, user=None, group=None):
'''
Ensures a ceph keyring is created for a named service
and optionally ensures user and group ownership.
Returns False if no ceph key is available in relation state.
'''
key = None
for rid in relation_ids('ceph'):
for unit in related_units(rid):
key = relation_get('key', rid=rid, unit=unit)
if key:
break
if not key:
return False
create_keyring(service=service, key=key)
keyring = _keyring_path(service)
if user and group:
check_call(['chown', '%s.%s' % (user, group), keyring])
return True
def ceph_version():
''' Retrieve the local version of ceph '''
if os.path.exists('/usr/bin/ceph'):
cmd = ['ceph', '-v']
output = check_output(cmd)
output = output.split()
if len(output) > 3:
return output[2]
else:
return None
else:
return None