Merge "backups: add retirement and purge lists"

doc/source/sysadmin.rst

@@ -262,6 +262,19 @@ then monthly backups for 1 year and yearly backups for each archive.
 The backup servers will send a warning when backup volume usage is
 high, at which point this can be run manually.
 
+Retiring hosts
+--------------
+
+When a host that runs backups is retired, it should have its user
+added to the `borg_retire_users` list (this list can differ per-backup
+server, depending on storage requirements).  Retired users will have
+their backup accounts disabled and we will only keep the latest backup
+revision.
+
+When we are ready to completely remove the backups, the user can be
+moved to the `borg_purge_users` list, which will purge all borg
+backups on the next ansible run.
+
 .. _force-merging-a-change:
 
 Force-Merging a Change

playbooks/roles/borg-backup-server/README.rst

@@ -13,3 +13,18 @@ Their ``authorized_keys`` file is configured with the public key to
 allow the remote host to log in and only run ``borg`` in server mode.
 
 **Role Variables**
+
+.. zuul:rolevar:: borg_retire_users
+   :default: []
+
+   A list of backup user names that are in a "retired" state.  The
+   host should not be in the inventory or active.  The backup user
+   will be diabled and when running a prune, we will only keep the
+   latest backup to save space.
+
+.. zuul:rolevar:: borg_purge_users
+   default: []
+
+   A list of backup user names whose data should be purged.  This list
+   represents backups for hosts that have been retired and we now
+   agree we do not want to retain any of their data.

playbooks/roles/borg-backup-server/defaults/main.yaml

@@ -1 +1,3 @@
 borg_users: []
+borg_retire_users: []
+borg_purge_users: []

playbooks/roles/borg-backup-server/files/prune-borg-backups.sh

@@ -10,10 +10,12 @@ if [[ ${borg_op} == 'noop' ]]; then
     BORG_OP='--dry-run'
 elif [[ ${borg_op} == 'prune' ]]; then
     BORG_OP=''
+    if [ -z ${NO_LOG_FILE+x} ]; then
         LOG_FILE="/opt/backups/prune-$(date '+%Y-%m-%d-%H-%M-%S').log"
         echo "*** Logging output to ${LOG_FILE}"
         exec 1>${LOG_FILE}
         exec 2>&1
+    fi
 else
     echo "*** Invalid input"
     exit 1
@@ -22,25 +24,39 @@ fi
 pushd /opt/backups
 
 for u in borg-*; do
-    BORG_REPO=/opt/backups/$u/backup
+    BORG_BASE=/opt/backups/$u
+    BORG_REPO=${BORG_BASE}/backup
 
-    sudo BORG_OP=${BORG_OP} BORG_RELOCATED_REPO_ACCESS_IS_OK=y BORG_REPO=${BORG_REPO} -u ${u} -s  <<'EOF'
+    _prune_flags='--keep-daily 7 --keep-weekly 4 --keep-monthly 12'
+    _retired=''
+    if [[ -f ${BORG_BASE}/.retired ]]; then
+        _prune_flags='--keep-daily 1'
+        _retired=' (retired)'
+    fi
+
+    sudo BORG_OP=${BORG_OP} BORG_UNKNOWN_UNENCRYPTED_REPO_ACCESS_IS_OK=yes BORG_REPO=${BORG_REPO} _retired="${_retired}" _prune_flags="${_prune_flags}" -u ${u} -s  <<'EOF'
 
     # Look at all archives and strip the timestamp, leaving just the archive names
     # We limit the prune by --prefix so each archive is considered separately
     # Long-running aborted backups might leave a ".checkpoint" archive around; ignore
     # these as prune will remove them automatically
+    #
+    # Note we are assuming the archives are in the format made by our backup scripts,
+    # which include -YYYY-MM-DDTHH:MM:SS on the end.
     archives=$(/opt/borg/bin/borg list ${BORG_REPO} | awk '$1 !~ /\.checkpoint$/ { print substr($1, 0, length($1)-20) }' | sort | uniq)
 
+    echo "+------"
+    echo "| $(date) Pruning ${BORG_REPO}${_retired}"
+
     for prefix in ${archives};
     do
-      echo
-      echo
-      echo "+------"
-      echo "| $(date) Pruning ${BORG_REPO} archive ${prefix}"
-      echo "+------"
-     /opt/borg/bin/borg prune --prefix ${prefix} ${BORG_OP} --verbose --list --show-rc --keep-daily 7 --keep-weekly 4 --keep-monthly 12
+       echo "| $(date) - archive ${prefix}"
+      /opt/borg/bin/borg prune --prefix ${prefix} ${BORG_OP} --verbose --list --show-rc ${_prune_flags}
     done
 
+    echo "| $(date) done!"
+    echo "+------"
+    echo
+
 EOF
 done

playbooks/roles/borg-backup-server/tasks/main.yaml

@@ -64,3 +64,15 @@
   loop: '{{ borg_users }}'
   loop_control:
     loop_var: borg_user
+
+- name: Remove purged user's backup dirs
+  file:
+    name: '/opt/backups/{{ item }}/backup'
+    state: absent
+  loop: '{{ borg_purge_users }}'
+
+- name: Disable retired users
+  include_tasks: retire.yaml
+  loop: '{{ borg_retire_users }}'
+  loop_control:
+    loop_var: borg_user

playbooks/roles/borg-backup-server/tasks/retire.yaml

@@ -0,0 +1,17 @@
+- name: Disable backup user login
+  user:
+    name: '{{ borg_user }}'
+    shell: /bin/nologin
+
+- name: Remove ssh key
+  file:
+    name: '/opt/backups/{{ borg_user }}/.ssh'
+    state: absent
+
+- name: Mark as retired
+  file:
+    name: '/opt/backups/{{ borg_user }}/.retired'
+    state: touch
+    owner: '{{ borg_user }}'
+    group: '{{ borg_user }}'
+    mode: 0644

playbooks/test-borg-backup-pre.yaml

@@ -0,0 +1,31 @@
+- hosts: "borg-backup-server"
+  tasks:
+    - name: Setup backup area
+      file:
+        name: '/opt/backups/'
+        state: directory
+        mode: 0755
+        owner: root
+        group: root
+
+    # We put this in borg_retire_users and check it gets
+    # marked as retired
+    - name: Setup fake retired user
+      user:
+        name: borg-retired
+        home: '/opt/backups/borg-retired'
+
+    # We put "borg-purge" in borg_purge_users and check it's
+    # backup directory gets removed.
+    - name: Setup fake purge user
+      user:
+        name: borg-purge
+        home: '/opt/backups/borg-purge'
+
+    - name: Setup fake purge user backup directory
+      file:
+        name: '/opt/backups/borg-purge/backup'
+        state: directory
+        mode: 0755
+        owner: borg-purge
+        group: borg-purge

playbooks/zuul/run-base.yaml

@@ -140,6 +140,7 @@
         - group_vars/zuul-merger.yaml
         - group_vars/zuul-scheduler.yaml
         - group_vars/zuul-web.yaml
+        - host_vars/borg-backup01.region.provider.opendev.org.yaml
         - host_vars/codesearch01.opendev.org.yaml
         - host_vars/etherpad99.opendev.org.yaml
         - host_vars/letsencrypt01.opendev.org.yaml

playbooks/zuul/templates/host_vars/borg-backup01.region.provider.opendev.org.yaml.j2

@@ -0,0 +1,4 @@
+borg_retire_users:
+  - borg-retired
+borg_purge_users:
+  - borg-purge

testinfra/test_borg_backups.py

@@ -54,6 +54,14 @@ def test_borg_server_users(host):
         f = host.file(borg_repo)
         assert f.exists
 
+    # test retired stamp is made for host in retired group
+    f = host.file('/opt/backups/borg-retired/.retired')
+    assert f.exists
+
+    # test purge for host in purge group
+    f = host.file('/opt/backups/borg-purge/backup')
+    assert not f.exists
+
 def test_borg_backup_host_config(host):
     hostname = host.backend.get_hostname()
     if hostname == 'borg-backup01.region.provider.opendev.org':
@@ -97,7 +105,19 @@ def test_borg_server_prune(host):
     if hostname != 'borg-backup01.region.provider.opendev.org':
         pytest.skip()
 
-    cmd = host.run('echo "prune" | /usr/local/bin/prune-borg-backups &> /var/log/prune-borg-backups.log')
+    # bit of a hack; instead of making a host, backing it up, and then
+    # retiring it -- which would require testing multiple runs of the
+    # backup process -- simulate the retired user being active by just
+    # making a small archive.  This ensure the prune script works on
+    # user flagged as retired.
+    cmd = host.run('dd if=/dev/urandom of=/tmp/borg-backup.random bs=1M count=5')
+    assert cmd.succeeded
+    cmd = host.run('sudo -u borg-retired /opt/borg/bin/borg init --encryption=none /opt/backups/borg-retired/backup')
+    assert cmd.succeeded
+    cmd = host.run('sudo -u borg-retired /opt/borg/bin/borg create /opt/backups/borg-retired/backup::test-9999-12-12T00:00:00 /tmp/borg-backup.random')
+    assert cmd.succeeded
+
+    cmd = host.run('echo "prune" | NO_LOG_FILE=1 /usr/local/bin/prune-borg-backups &> /var/log/prune-borg-backups.log')
     assert cmd.succeeded
 
 def test_borg_server_verify(host):

zuul.d/system-config-run.yaml

@@ -427,6 +427,7 @@
         - <<: *bastion_group
     vars:
       run_playbooks:
+        - playbooks/test-borg-backup-pre.yaml
         - playbooks/service-borg-backup.yaml
       run_test_playbook: playbooks/test-borg-backup.yaml
     files: