20 KiB
CEPH Storage Automation Patterns
Best practices for automating CEPH cluster deployment in Proxmox VE environments.
Pattern: Declarative CEPH OSD Configuration
Problem: ProxSpray leaves OSD creation as a manual step, defeating the purpose of automation.
Solution: Fully automate OSD creation with declarative configuration that specifies devices and partitioning.
Configuration Model
# group_vars/matrix_cluster.yml
---
# CEPH network configuration
ceph_enabled: true
ceph_network: "192.168.5.0/24" # Public network (vmbr1)
ceph_cluster_network: "192.168.7.0/24" # Private network (vmbr2)
# OSD configuration per node (4 OSDs per node = 12 total)
ceph_osds:
foxtrot:
- device: /dev/nvme1n1
partitions: 2 # Create 2 OSDs per 4TB NVMe
db_device: null
wal_device: null
crush_device_class: nvme
- device: /dev/nvme2n1
partitions: 2
db_device: null
wal_device: null
crush_device_class: nvme
golf:
- device: /dev/nvme1n1
partitions: 2
crush_device_class: nvme
- device: /dev/nvme2n1
partitions: 2
crush_device_class: nvme
hotel:
- device: /dev/nvme1n1
partitions: 2
crush_device_class: nvme
- device: /dev/nvme2n1
partitions: 2
crush_device_class: nvme
# Pool configuration
ceph_pools:
- name: vm_ssd
pg_num: 128
pgp_num: 128
size: 3 # Replicate across 3 nodes
min_size: 2 # Minimum 2 replicas required
application: rbd
crush_rule: replicated_rule
compression: false
- name: vm_containers
pg_num: 64
pgp_num: 64
size: 3
min_size: 2
application: rbd
crush_rule: replicated_rule
compression: true
Pattern: Idempotent CEPH Installation
Problem: CEPH installation commands fail if already installed.
Solution: Check CEPH status before attempting installation.
Implementation
# roles/proxmox_ceph/tasks/install.yml
---
- name: Check if CEPH is already installed
ansible.builtin.stat:
path: /etc/pve/ceph.conf
register: ceph_conf_check
- name: Check CEPH packages
ansible.builtin.command:
cmd: dpkg -l ceph-common
register: ceph_package_check
failed_when: false
changed_when: false
- name: Install CEPH packages
ansible.builtin.command:
cmd: "pveceph install --repository no-subscription"
when:
- ceph_package_check.rc != 0
register: ceph_install
changed_when: "'installed' in ceph_install.stdout"
- name: Verify CEPH installation
ansible.builtin.command:
cmd: ceph --version
register: ceph_version
changed_when: false
failed_when: ceph_version.rc != 0
Pattern: CEPH Cluster Initialization
Problem: CEPH cluster can only be initialized once, must be idempotent.
Solution: Check for existing cluster configuration before initialization.
Implementation
# roles/proxmox_ceph/tasks/init.yml
---
- name: Check if CEPH cluster is initialized
ansible.builtin.command:
cmd: ceph status
register: ceph_status_check
failed_when: false
changed_when: false
- name: Set CEPH initialization facts
ansible.builtin.set_fact:
ceph_initialized: "{{ ceph_status_check.rc == 0 }}"
is_ceph_first_node: "{{ inventory_hostname == groups[cluster_group][0] }}"
- name: Initialize CEPH cluster on first node
ansible.builtin.command:
cmd: "pveceph init --network {{ ceph_network }} --cluster-network {{ ceph_cluster_network }}"
when:
- is_ceph_first_node | default(false)
- not ceph_initialized
register: ceph_init
changed_when: ceph_init.rc == 0
- name: Wait for CEPH cluster to initialize
ansible.builtin.pause:
seconds: 15
when: ceph_init.changed
Pattern: CEPH Monitor Creation
Problem: Monitors must be created in specific order and verified for quorum.
Solution: Create monitors with proper ordering and quorum verification.
Implementation
# roles/proxmox_ceph/tasks/monitors.yml
---
- name: Check existing CEPH monitors
ansible.builtin.command:
cmd: ceph mon dump
register: mon_dump
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
failed_when: false
changed_when: false
- name: Set monitor facts
ansible.builtin.set_fact:
has_monitor: "{{ inventory_hostname in mon_dump.stdout }}"
when: mon_dump.rc == 0
- name: Set local is_ceph_first_node fact
ansible.builtin.set_fact:
is_ceph_first_node: "{{ inventory_hostname == groups[cluster_group][0] }}"
- name: Create CEPH monitor on first node
ansible.builtin.command:
cmd: pveceph mon create
when:
- is_ceph_first_node | default(false)
- not has_monitor | default(false)
register: mon_create_first
changed_when: mon_create_first.rc == 0
- name: Wait for first monitor to stabilize
ansible.builtin.pause:
seconds: 10
when: mon_create_first.changed
- name: Create CEPH monitors on other nodes
ansible.builtin.command:
cmd: pveceph mon create
when:
- not (is_ceph_first_node | default(false))
- not has_monitor | default(false)
register: mon_create_others
changed_when: mon_create_others.rc == 0
- name: Verify monitor quorum
ansible.builtin.command:
cmd: ceph quorum_status
register: quorum_status
changed_when: false
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
vars:
expected_mons: "{{ ceph_mon_count | default(3) }}"
failed_when: ((quorum_status.stdout | from_json).quorum | length) < expected_mons
Pattern: CEPH Manager Creation
Problem: Managers provide web interface and monitoring; should run on all nodes for HA.
Solution: Create managers on all nodes with proper verification.
Implementation
# roles/proxmox_ceph/tasks/managers.yml
---
- name: Check existing CEPH managers
ansible.builtin.command:
cmd: ceph mgr dump
register: mgr_dump
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
failed_when: false
changed_when: false
- name: Set manager facts
ansible.builtin.set_fact:
has_manager: "{{ inventory_hostname in mgr_dump.stdout }}"
when: mgr_dump.rc == 0
- name: Create CEPH manager
ansible.builtin.command:
cmd: pveceph mgr create
when: not has_manager | default(false)
register: mgr_create
changed_when: mgr_create.rc == 0
- name: Enable CEPH dashboard module
ansible.builtin.command:
cmd: ceph mgr module enable dashboard
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
register: dashboard_enable
changed_when: "'already enabled' not in dashboard_enable.stderr"
failed_when:
- dashboard_enable.rc != 0
- "'already enabled' not in dashboard_enable.stderr"
Pattern: Automated OSD Creation with Partitioning
Problem: Manual OSD creation is error-prone and doesn't support partitioning large drives.
Solution: Automate partition creation and OSD deployment.
Implementation
# roles/proxmox_ceph/tasks/osd_create.yml
---
- name: Get list of existing OSDs
ansible.builtin.command:
cmd: pveceph osd ls
register: existing_osds
changed_when: false
failed_when: false
- name: Probe existing CEPH volumes
ansible.builtin.command:
cmd: ceph-volume lvm list --format json
register: ceph_volume_probe
changed_when: false
failed_when: false
- name: Check OSD devices availability
ansible.builtin.command:
cmd: "lsblk -ndo NAME,TYPE {{ item.device }}"
register: device_check
failed_when: device_check.rc != 0
changed_when: false
loop: "{{ ceph_osds[inventory_hostname_short] | default([]) }}"
loop_control:
label: "{{ item.device }}"
- name: Wipe existing partitions on OSD devices
ansible.builtin.command:
cmd: "wipefs -a {{ item.device }}"
when:
- ceph_volume_probe.rc == 0
- ceph_volume_probe.stdout | from_json | dict2items | selectattr('value.0.devices', 'defined') | map(attribute='value.0.devices') | flatten | select('match', '^' + item.device) | list | length == 0
- ceph_wipe_disks | default(false)
loop: "{{ ceph_osds[inventory_hostname_short] | default([]) }}"
loop_control:
label: "{{ item.device }}"
register: wipe_result
changed_when: wipe_result.rc == 0
- name: Build list of partitions to create
ansible.builtin.set_fact:
osd_partitions: >-
{% set result = [] -%}
{% for osd in ceph_osds[inventory_hostname_short] | default([]) -%}
{% if (osd.partitions | default(1) | int) > 1 -%}
{% for part_num in range(1, (osd.partitions | int) + 1) -%}
{% set _ = result.append({
'device': osd.device,
'partition_num': part_num,
'total_partitions': osd.partitions,
'db_device': osd.get('db_device'),
'wal_device': osd.get('wal_device')
}) -%}
{% endfor -%}
{% endif -%}
{% endfor -%}
{{ result }}
- name: Create partitions for multiple OSDs per device
community.general.parted:
device: "{{ item.device }}"
number: "{{ item.partition_num }}"
state: present
part_start: "{{ ((item.partition_num - 1) * (100 / item.total_partitions)) }}%"
part_end: "{{ (item.partition_num * (100 / item.total_partitions)) }}%"
label: gpt
loop: "{{ osd_partitions }}"
loop_control:
label: "{{ item.device }}{{ 'p' if item.device.startswith('/dev/nvme') else '' }}{{ item.partition_num }}"
- name: Create OSDs from whole devices
ansible.builtin.command:
cmd: >
pveceph osd create {{ item.device }}
{% if item.db_device %}--db_dev {{ item.db_device }}{% endif %}
{% if item.wal_device %}--wal_dev {{ item.wal_device }}{% endif %}
when:
- item.partitions | default(1) == 1
- ceph_volume_probe.rc == 0
- ceph_volume_probe.stdout | from_json | dict2items | selectattr('value.0.devices', 'defined') | map(attribute='value.0.devices') | flatten | select('match', '^' + item.device + '$') | list | length == 0
loop: "{{ ceph_osds[inventory_hostname_short] | default([]) }}"
loop_control:
label: "{{ item.device }}"
register: osd_create_whole
changed_when: "'successfully created' in osd_create_whole.stdout"
failed_when:
- osd_create_whole.rc != 0
- "'already in use' not in osd_create_whole.stderr"
- name: Create OSDs from partitions
ansible.builtin.command:
cmd: >
pveceph osd create {{ item.device }}{{ 'p' if item.device.startswith('/dev/nvme') else '' }}{{ item.partition_num }}
{% if item.db_device %}--db_dev {{ item.db_device }}{% endif %}
{% if item.wal_device %}--wal_dev {{ item.wal_device %}{% endif %}
when:
- ceph_volume_probe.rc == 0
- ceph_volume_probe.stdout | from_json | dict2items | selectattr('value.0.devices', 'defined') | map(attribute='value.0.devices') | flatten | select('match', '^' + item.device + ('p' if item.device.startswith('/dev/nvme') else '') + (item.partition_num | string) + '$') | list | length == 0
loop: "{{ osd_partitions }}"
loop_control:
label: "{{ item.device }}{{ 'p' if item.device.startswith('/dev/nvme') else '' }}{{ item.partition_num }}"
register: osd_create_partition
changed_when: "'successfully created' in osd_create_partition.stdout"
failed_when:
- osd_create_partition.rc != 0
- "'already in use' not in osd_create_partition.stderr"
- name: Wait for OSDs to come up
ansible.builtin.command:
cmd: ceph osd tree
register: osd_tree
changed_when: false
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
until: "'up' in osd_tree.stdout"
retries: 10
delay: 5
Pattern: CEPH Pool Creation
Problem: Pools must be created with proper PG counts, replication, and application tags.
Solution: Declarative pool configuration with validation.
Implementation
# roles/proxmox_ceph/tasks/pools.yml
---
- name: Get existing CEPH pools
ansible.builtin.command:
cmd: ceph osd pool ls
register: existing_pools
changed_when: false
- name: Create CEPH pools
ansible.builtin.command:
cmd: >
ceph osd pool create {{ item.name }}
{{ item.pg_num }}
{{ item.pgp_num | default(item.pg_num) }}
replicated
{{ item.crush_rule | default('replicated_rule') }}
when: item.name not in existing_pools.stdout_lines
loop: "{{ ceph_pools }}"
loop_control:
label: "{{ item.name }}"
register: pool_create
changed_when: pool_create.rc == 0
- name: Get current pool replication size
ansible.builtin.command:
cmd: "ceph osd pool get {{ item.name }} size -f json"
loop: "{{ ceph_pools }}"
loop_control:
label: "{{ item.name }}"
register: pool_size_current
changed_when: false
- name: Set pool replication size
ansible.builtin.command:
cmd: "ceph osd pool set {{ item.name }} size {{ item.size }}"
when: (pool_size_current.results[loop_index].stdout | from_json).size != item.size
loop: "{{ ceph_pools }}"
loop_control:
label: "{{ item.name }}"
index_var: loop_index
- name: Get current pool minimum replication size
ansible.builtin.command:
cmd: "ceph osd pool get {{ item.name }} min_size -f json"
loop: "{{ ceph_pools }}"
loop_control:
label: "{{ item.name }}"
register: pool_min_size_current
changed_when: false
- name: Set pool minimum replication size
ansible.builtin.command:
cmd: "ceph osd pool set {{ item.name }} min_size {{ item.min_size }}"
when: (pool_min_size_current.results[loop_index].stdout | from_json).min_size != item.min_size
loop: "{{ ceph_pools }}"
loop_control:
label: "{{ item.name }}"
index_var: loop_index
- name: Get current pool applications
ansible.builtin.command:
cmd: "ceph osd pool application get {{ item.name }} -f json"
when: item.application is defined
loop: "{{ ceph_pools }}"
loop_control:
label: "{{ item.name }}"
register: pool_app_current
changed_when: false
failed_when: false
- name: Set pool application
ansible.builtin.command:
cmd: "ceph osd pool application enable {{ item.name }} {{ item.application }}"
when:
- item.application is defined
- pool_app_current.results[loop_index].rc == 0
- item.application not in (pool_app_current.results[loop_index].stdout | from_json | default({}))
loop: "{{ ceph_pools }}"
loop_control:
label: "{{ item.name }}"
index_var: loop_index
- name: Get current pool compression mode
ansible.builtin.command:
cmd: "ceph osd pool get {{ item.name }} compression_mode -f json"
when: item.compression | default(false)
loop: "{{ ceph_pools }}"
loop_control:
label: "{{ item.name }}"
register: pool_compression_current
changed_when: false
- name: Enable compression on pools
ansible.builtin.command:
cmd: "ceph osd pool set {{ item.name }} compression_mode aggressive"
when:
- item.compression | default(false)
- (pool_compression_current.results[loop_index].stdout | from_json).compression_mode != 'aggressive'
loop: "{{ ceph_pools }}"
loop_control:
label: "{{ item.name }}"
index_var: loop_index
Pattern: CEPH Health Verification
Problem: CEPH cluster may appear successful but have health issues.
Solution: Comprehensive health checks after deployment.
Implementation
# roles/proxmox_ceph/tasks/verify.yml
---
- name: Check CEPH cluster health
ansible.builtin.command:
cmd: ceph health
register: ceph_health
changed_when: false
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
- name: Get CEPH status
ansible.builtin.command:
cmd: ceph status
register: ceph_status
changed_when: false
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
- name: Verify expected OSD count
ansible.builtin.set_fact:
expected_osd_count: >-
{{
ceph_osds
| dict2items
| map(attribute='value')
| sum(start=[])
| map('default', {'partitions': 1})
| map(attribute='partitions')
| map('int')
| sum
}}
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
- name: Check OSD count matches expected
ansible.builtin.assert:
that:
- "(ceph_status.stdout | from_json).osdmap.num_osds == (expected_osd_count | int)"
fail_msg: >-
Expected {{ expected_osd_count }} OSDs but found
{{ (ceph_status.stdout | from_json).osdmap.num_osds }}
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
- name: Check all OSDs are up
ansible.builtin.command:
cmd: ceph osd tree
register: osd_tree
changed_when: false
failed_when: "'down' in osd_tree.stdout"
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
- name: Verify PG status
ansible.builtin.command:
cmd: ceph pg stat
register: pg_stat
changed_when: false
failed_when: "'active+clean' not in pg_stat.stdout"
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
retries: 30
delay: 10
until: "'active+clean' in pg_stat.stdout"
- name: Display CEPH status
ansible.builtin.debug:
msg: |
CEPH Cluster Health: {{ ceph_health.stdout }}
{{ ceph_status.stdout_lines | join('\n') }}
delegate_to: "{{ groups[cluster_group][0] }}"
run_once: true
Anti-Pattern: Manual OSD Creation
❌ Don't Do This (from ProxSpray):
- name: Create OSD on available disks (manual step required)
ansible.builtin.debug:
msg: |
To create OSDs, run manually:
pveceph osd create /dev/sda
pveceph osd create /dev/sdb
Problems:
- Defeats purpose of automation
- Error-prone manual process
- No consistency across nodes
- Difficult to scale
✅ Do This Instead: Use the declarative OSD configuration pattern shown above.
Complete Role Example
# roles/proxmox_ceph/tasks/main.yml
---
- name: Install CEPH packages
ansible.builtin.include_tasks: install.yml
- name: Initialize CEPH cluster (first node only)
ansible.builtin.include_tasks: init.yml
when: inventory_hostname == groups[cluster_group][0]
- name: Create CEPH monitors
ansible.builtin.include_tasks: monitors.yml
- name: Create CEPH managers
ansible.builtin.include_tasks: managers.yml
- name: Create OSDs
ansible.builtin.include_tasks: osd_create.yml
when: ceph_osds[inventory_hostname_short] is defined
- name: Create CEPH pools
ansible.builtin.include_tasks: pools.yml
when: inventory_hostname == groups[cluster_group][0]
- name: Verify CEPH health
ansible.builtin.include_tasks: verify.yml
Testing
# Syntax check
ansible-playbook --syntax-check playbooks/ceph-deploy.yml
# Check mode (limited - CEPH commands don't support check mode well)
ansible-playbook playbooks/ceph-deploy.yml --check --diff
# Deploy CEPH to Matrix cluster
ansible-playbook playbooks/ceph-deploy.yml --limit matrix_cluster
# Verify CEPH status
ansible -i inventory/proxmox.yml foxtrot -m shell -a "ceph status"
ansible -i inventory/proxmox.yml foxtrot -m shell -a "ceph osd tree"
ansible -i inventory/proxmox.yml foxtrot -m shell -a "ceph health detail"
Matrix Cluster Example
# playbooks/ceph-deploy.yml
---
- name: Deploy CEPH Storage on Matrix Cluster
hosts: matrix_cluster
become: true
serial: 1 # Deploy one node at a time
pre_tasks:
- name: Verify network MTU
ansible.builtin.command:
cmd: "ip link show vmbr1"
register: mtu_check
changed_when: false
failed_when: "'mtu 9000' not in mtu_check.stdout"
roles:
- role: proxmox_ceph
vars:
cluster_group: matrix_cluster
ceph_wipe_disks: false # Set to true for fresh deployment
Related Patterns
- Cluster Automation - Cluster formation prerequisite
- Network Automation - Network configuration for CEPH
- Error Handling - CEPH-specific error handling
References
- ProxSpray analysis:
docs/proxspray-analysis.md(lines 333-488) - Proxmox VE CEPH documentation
- CEPH configuration reference
- OSD deployment best practices