microstack/snap/hooks/remove
Dmitrii Shcherbakov 780a4c4ead Use focal/core20/Ussuri/OVN & enable confinement
Major changes:

* Plumbing necessary for strict confinement with
  the microstack-support interface
  https://github.com/snapcore/snapd/pull/8926
  * Until the interface is merged, devmode will be used and kernel
    modules will be loaded via an auxiliary service.
* upgraded OpenStack components to Focal (20.04) and OpenStack Ussuri;
  * reworked the old patches;
  * added the Placement service since it is now separate;
  * addressed various build issues due to changes in snapcraft and
    built dependencies:
    * e.g. libvirt requires the build directory to be separate from the
      source directory) and LP: #1882255;
    * LP: #1882535 and https://github.com/pypa/pip/issues/8414
    * LP: #1882839
    * LP: #1885294
    * https://storyboard.openstack.org/#!/story/2007806
    * LP: #1864589
    * LP: #1777121
    * LP: #1881590
* ML2/OVS replated with ML2/OVN;
  * dnsmasq is not used anymore;
  * neutron l3 and DHCP agents are not used anymore;
  * Linux network namespaces are only used for
    neutron-ovn-metadata-agent.
  * ML2 DNS support is done via native OVN mechanisms;
  * OVN-related database services (southbound and northbound dbs);
  * OVN-related control plane services (ovn-controller, ovn-northd);
* core20 base support (bionic hosts are supported);
* the removal procedure now relies on the "remove" hook since `snap
remove` cannot be used from the confined environment anymore;
* prerequisites to enabling AppArmor confinement for QEMU processes
  created by the confined libvirtd.
* Added the Spice html5 console proxy service to enable clients to
  retrieve and use it via
  `microstack.openstack console url show --spice <servername>`.
* Added missing Cinder templates and DB migrations for the Cinder DB.
* Added experimental support for a loop device-based LVM backend for
  Cinder. Due to LP: #1892895 this is not recommended to be used in
  production except for tempest testing with an applied workaround;
  * includes iscsid and iscsi-tcp kernel module loading;
  * includes LIO and loading of relevant kernel modules;
  * An LVM PV is created on top of a loop device with a backing file
  present in $SNAP_COMMON/cinder-lvm.img;
  * A VG is created on top of the PV;
  * LVs are created by Cinder and exported via LIO over iscsi to iscsid
  which hot-plugs new SCSI devices. Those SCSI devices are then
  propagated by Nova to libvirt and QEMU during volume attachment;
* Added post-deployment testing via rally and tempest (via the
  microstack-test snap). A set of tests included into Refstack 2018.02
  is executed (except for object storage tests due to the lack of object
  storage support).

Change-Id: Ic70770095860a57d5e0a55a8a9451f9db6be7448
2020-09-25 13:20:12 +00:00

80 lines
3.2 KiB
Python
Executable File

#!/usr/bin/env python3
import os
import sys
import logging
from subprocess import check_call, check_output, call, run
from pyroute2 import netns
logging.basicConfig(stream=sys.stdout, level=logging.DEBUG)
if __name__ == '__main__':
# Work around the lack of modified LD_LIBRARY_PATH and PATH variables with
# snap-specific content.
snap_dir = os.environ['SNAP']
snap_libs = (f'{snap_dir}/lib:{snap_dir}/usr/lib:'
f'{snap_dir}/lib/x86_64-linux-gnu:'
f'{snap_dir}/usr/lib/x86_64-linux-gnu')
os.environ['LD_LIBRARY_PATH'] = snap_libs
check_call(['snapctl', 'start', 'microstack.ovsdb-server'])
check_call(['snapctl', 'start', 'microstack.ovs-vswitchd'])
logging.info('Attempting to remove br-ex.')
check_call(['ovs-vsctl', '--if-exists', 'del-br', 'br-ex'])
check_call(['snapctl', 'stop', 'microstack.ovsdb-server'])
check_call(['snapctl', 'stop', 'microstack.ovs-vswitchd'])
for ns in netns.listnetns():
if ns.startswith('ovnmeta-'):
logging.info(f'Removing the {ns} network namespace.')
netns.remove(ns)
# Need to expose targets prior to starting iscsid in order to properly log out
# of iSCSI sessions.
check_call(['snapctl', 'start', 'microstack.target'])
check_call(['snapctl', 'start', 'microstack.iscsid'])
check_call(['sync'])
# Assuming the QEMU processes have already been killed by snapd,
# log out of all targets prior to removing the snap to clean up
# the kernel state.
# TODO: be more selective about logging out since there may be sessions
# unrelated to MicroStack in the kernel.
# TODO: also clean up block devices by writing to
# /sys/class/block/<dev>/device/delete since those do not get deleted on
# session logout.
logging.info('Attempting to remove iscsi sessions from the kernel.')
res = run(['iscsiadm', '-m', 'node', '-u'])
# ISCSI_ERR_NO_OBJS_FOUND
if res.returncode == 21:
logging.debug('No iscsi sessions were found.')
elif res.returncode == 0:
logging.debug('Successfully logged the existing iscsi sessions out.')
else:
# Albeit this is an error condition we cannot do much in the remove
# hook to fix this besides logging since snapd does not stop the
# snap removal on error in the remove hook.
logging.error('Unexpected error code received from iscsiadm: '
f'{res.returncode}')
check_call(['snapctl', 'stop', 'microstack.iscsid'])
check_call(['snapctl', 'stop', 'microstack.target'])
# File-backed LVM resource cleanup (if present).
loop_file = f'{os.environ["SNAP_COMMON"]}/cinder-lvm.img'
allocated_loop_dev = check_output(
f'losetup -j {loop_file} | cut -d ":" -f 1', shell=True
).decode('utf-8').strip()
if allocated_loop_dev:
cinder_lvm_vg = check_output([
'snapctl', 'get', 'config.cinder.lvm-backend-volume-group']
).strip()
if not call(['vgdisplay', cinder_lvm_vg]):
check_call(['vgremove', '-f', cinder_lvm_vg])
if not call(['pvdisplay', allocated_loop_dev]):
check_call(['pvremove', '-f', allocated_loop_dev])
check_call(['losetup', '-d', allocated_loop_dev])