Chapter 2. Creating an Overcloud with Ceph Storage Nodes

Log into the director host as the stack user and run the following command to initialize your director configuration:

$ source ~/stackrc

This sets up environment variables containing authentication details to access the director’s CLI tools.

A node definition template (instackenv.json) is a JSON format file and contains the hardware and power management details for registering nodes. For example:

{
    "nodes":[
        {
            "mac":[
                "b1:b1:b1:b1:b1:b1"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.205"
        },
        {
            "mac":[
                "b2:b2:b2:b2:b2:b2"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.206"
        },
        {
            "mac":[
                "b3:b3:b3:b3:b3:b3"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.207"
        },
        {
            "mac":[
                "c1:c1:c1:c1:c1:c1"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.208"
        },
        {
            "mac":[
                "c2:c2:c2:c2:c2:c2"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.209"
        },
        {
            "mac":[
                "c3:c3:c3:c3:c3:c3"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.210"
        },
        {
            "mac":[
                "d1:d1:d1:d1:d1:d1"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.211"
        },
        {
            "mac":[
                "d2:d2:d2:d2:d2:d2"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.212"
        },
        {
            "mac":[
                "d3:d3:d3:d3:d3:d3"
            ],
            "cpu":"4",
            "memory":"6144",
            "disk":"40",
            "arch":"x86_64",
            "pm_type":"pxe_ipmitool",
            "pm_user":"admin",
            "pm_password":"p@55w0rd!",
            "pm_addr":"192.0.2.213"
        }
    ]
}

After creating the template, save the file to the stack user’s home directory (/home/stack/instackenv.json), then import it into the director. Use the following command to accomplish this:

$ openstack baremetal import --json ~/instackenv.json

This imports the template and registers each node from the template into the director.

Assign the kernel and ramdisk images to all nodes:

$ openstack baremetal configure boot

The nodes are now registered and configured in the director.

After registering the nodes, inspect the hardware attribute of each node. Run the following command to inspect the hardware attributes of each node:

$ openstack baremetal introspection bulk start

After registering and inspecting the hardware of each node, tag them into specific profiles. These profile tags match your nodes to flavors, and in turn the flavors are assigned to a deployment role.

Retrieve a list of your nodes to identify their UUIDs:

$ ironic node-list

To manually tag a node to a specific profile, add a profile option to the properties/capabilities parameter for each node. For example, to tag three nodes to use a controller profile and one node to use a compute profile, use the following commands:

$ ironic node-update 1a4e30da-b6dc-499d-ba87-0bd8a3819bc0 add properties/capabilities='profile:control,boot_option:local'
$ ironic node-update 6faba1a9-e2d8-4b7c-95a2-c7fbdc12129a add properties/capabilities='profile:control,boot_option:local'
$ ironic node-update 5e3b2f50-fcd9-4404-b0a2-59d79924b38e add properties/capabilities='profile:control,boot_option:local'
$ ironic node-update 484587b2-b3b3-40d5-925b-a26a2fa3036f add properties/capabilities='profile:compute,boot_option:local'
$ ironic node-update d010460b-38f2-4800-9cc4-d69f0d067efe add properties/capabilities='profile:compute,boot_option:local'
$ ironic node-update d930e613-3e14-44b9-8240-4f3559801ea6 add properties/capabilities='profile:compute,boot_option:local'
$ ironic node-update da0cc61b-4882-45e0-9f43-fab65cf4e52b add properties/capabilities='profile:ceph-storage,boot_option:local'
$ ironic node-update b9f70722-e124-4650-a9b1-aade8121b5ed add properties/capabilities='profile:ceph-storage,boot_option:local'
$ ironic node-update 68bf8f29-7731-4148-ba16-efb31ab8d34f add properties/capabilities='profile:ceph-storage,boot_option:local'

The addition of the profile option tags the nodes into each respective profiles.

Most Ceph Storage nodes use multiple disks. This means the director needs to identify the disk to use for the root disk when provisioning a Ceph Storage node. There are several properties you can use to help identify the root disk:

In this example, we specify the drive to deploy the Overcloud image using the serial number of the disk to determine the root device.

First, collect a copy of each node’s hardware information that the director obtained from the introspection. This information is stored in the OpenStack Object Storage server (swift). Download this information to a new directory:

$ mkdir swift-data
$ cd swift-data
$ export SWIFT_PASSWORD=`sudo crudini --get /etc/ironic-inspector/inspector.conf swift password`
$ for node in $(ironic node-list | grep -v UUID| awk '{print $2}'); do swift -U service:ironic -K $SWIFT_PASSWORD download ironic-inspector inspector_data-$node; done

This downloads the data from each inspector_data object from introspection. All objects use the node UUID as part of the object name:

$ ls -1
inspector_data-15fc0edc-eb8d-4c7f-8dc0-a2a25d5e09e3
inspector_data-46b90a4d-769b-4b26-bb93-50eaefcdb3f4
inspector_data-662376ed-faa8-409c-b8ef-212f9754c9c7
inspector_data-6fc70fe4-92ea-457b-9713-eed499eda206
inspector_data-9238a73a-ec8b-4976-9409-3fcff9a8dca3
inspector_data-9cbfe693-8d55-47c2-a9d5-10e059a14e07
inspector_data-ad31b32d-e607-4495-815c-2b55ee04cdb1
inspector_data-d376f613-bc3e-4c4b-ad21-847c4ec850f8

Check the disk information for each node. The following command displays each node ID and the disk information:

$ for node in $(ironic node-list | grep -v UUID| awk '{print $2}'); do echo "NODE: $node" ; cat inspector_data-$node | jq '.inventory.disks' ; echo "-----" ; done

For example, the data for one node might show three disk:

NODE: 15fc0edc-eb8d-4c7f-8dc0-a2a25d5e09e3
[
  {
    "size": 299439751168,
    "rotational": true,
    "vendor": "DELL",
    "name": "/dev/sda",
    "wwn_vendor_extension": "0x1ea4dcc412a9632b",
    "wwn_with_extension": "0x61866da04f3807001ea4dcc412a9632b",
    "model": "PERC H330 Mini",
    "wwn": "0x61866da04f380700",
    "serial": "61866da04f3807001ea4dcc412a9632b"
  }
  {
    "size": 299439751168,
    "rotational": true,
    "vendor": "DELL",
    "name": "/dev/sdb",
    "wwn_vendor_extension": "0x1ea4e13c12e36ad6",
    "wwn_with_extension": "0x61866da04f380d001ea4e13c12e36ad6",
    "model": "PERC H330 Mini",
    "wwn": "0x61866da04f380d00",
    "serial": "61866da04f380d001ea4e13c12e36ad6"
  }
  {
    "size": 299439751168,
    "rotational": true,
    "vendor": "DELL",
    "name": "/dev/sdc",
    "wwn_vendor_extension": "0x1ea4e31e121cfb45",
    "wwn_with_extension": "0x61866da04f37fc001ea4e31e121cfb45",
    "model": "PERC H330 Mini",
    "wwn": "0x61866da04f37fc00",
    "serial": "61866da04f37fc001ea4e31e121cfb45"
  }
]
-----

For this example, set the root device to disk 2, which has 61866da04f37fc001ea4e31e121cfb45 as the serial number. This requires a change to the root_device parameter for the node definition:

$ ironic node-update 15fc0edc-eb8d-4c7f-8dc0-a2a25d5e09e3 add properties/root_device='{"serial": "61866da04f37fc001ea4e31e121cfb45"}'

This helps the director identify the specific disk to use as the root disk. When we initiate our Overcloud creation, the director provisions this node and writes the Overcloud image to this disk. The other disks are used for mapping our Ceph Storage nodes.

The Overcloud image already contains the Ceph services and the necessary Puppet modules to automatically configure both the Ceph OSD nodes and the Ceph Monitor on Controller clusters. The Overcloud’s Heat template collection also contains the necessary procedures to enable your Ceph Storage configuration. However, the director requires some details to enable Ceph Storage and pass on the intended configuration. To pass this information, copy the storage-environment.yaml environment file to your stack user’s templates directory.

$ cp /usr/share/openstack-tripleo-heat-templates/environments/storage-environment.yaml ~/templates/.

Modify the following options in the copy of storage-environment.yaml:

Next, modify each entry in the resource_registry to point to the absolute path of each resource:

resource_registry:
  OS::TripleO::Services::CephMon: /usr/share/openstack-tripleo-heat-templates/puppet/services/ceph-mon.yaml
  OS::TripleO::Services::CephOSD: /usr/share/openstack-tripleo-heat-templates/puppet/services/ceph-osd.yaml
  OS::TripleO::Services::CephClient: /usr/share/openstack-tripleo-heat-templates/puppet/services/ceph-client.yaml

The default mapping uses the root disk for Ceph Storage. However, most production environments use multiple separate disks for storage and partitions for journaling. In this situation, you define a storage map as part of the storage-environment.yaml file copied previously.

Edit the storage-environment.yaml file and the following snippet to the parameter_defaults:

  ExtraConfig:
    ceph::profile::params::osds:

This adds extra Hiera data to the Overcloud, which Puppet uses as custom parameters during configuration. Use the ceph::profile::params::osds parameter to map the relevant disks and journal partitions. For example, a Ceph node with four disks might have the following assignments:

For this example, the mapping might contain the following:

    ceph::profile::params::osds:
        '/dev/sdc':
          journal: '/dev/sdb'
        '/dev/sdd':
          journal: '/dev/sdb'

If you do not want a separate disk for journals, use co-located journals on the OSD disks. Pass a blank value to the journal parameters:

    ceph::profile::params::osds:
        '/dev/sdb': {}
        '/dev/sdc': {}
        '/dev/sdd': {}

   ceph::profile::params::osds:
      '/dev/disk/by-path/pci-0000:00:17.0-ata-2-part1':
        journal: '/dev/nvme0n1'
      '/dev/disk/by-path/pci-0000:00:17.0-ata-2-part2':
        journal: '/dev/nvme0n1'

You can also deploy Ceph nodes with different types of disks (for example, SSD and SATA disks on the same physical host). In a typical Ceph deployment, this is configured through CRUSH maps, as described in Placing Different Pools on Different OSDS. If you are mapping such a deployment, add the following line to the ExtraConfig section of the storage-environment.yaml:

ceph::osd_crush_update_on_start: false

Afterwards, save the ~/templates/storage-environment.yaml file so that when we deploy the Overcloud, the Ceph Storage nodes use our disk mapping. We include this file in our deployment to initiate our storage requirements.

The Ceph Object Gateway provides applications with an interface to object storage capabilities within a Ceph storage cluster. Upon deploying the Ceph Object Gateway, you can then replace the default Object Storage service (swift) with Ceph. For more information, see Object Gateway Guide for Red Hat Enterprise Linux.

To enable a Ceph Object Gateway in your deployment, add the following snippet to the resource_registry of your environment file (namely, ~/templates/storage-environment.yaml):

  OS::TripleO::Services::CephRgw: /usr/share/openstack-tripleo-heat-templates/puppet/services/ceph-rgw.yaml
  OS::TripleO::Services::SwiftProxy: OS::Heat::None
  OS::TripleO::Services::SwiftStorage: OS::Heat::None
  OS::TripleO::Services::SwiftRingBuilder: OS::Heat::None

In addition to deploying the Ceph Object Gateway, this snippet also disables the default Object Storage service. (swift).

The Ceph Object Gateway acts as a drop-in replacement for the default Object Storage service. As such, all other services that normally use swift can seamlessly start using the Ceph Object Gateway instead without further configuration. For example, when configuring the Block Storage Backup service (cinder-backup) to use the Ceph Object Gateway, set swift as the target back end (see Section 2.9, “Configuring the Backup Service to Use Ceph”).

The Block Storage Backup service (cinder-backup) is disabled by default. You can enable it by adding the following line to the resource_registry of your environment file (namely, ~/templates/storage-environment.yaml):

  OS::TripleO::Services::CinderBackup: /usr/share/openstack-tripleo-heat-templates/puppet/services/pacemaker/cinder-backup.yaml

Next, configure the cinder-backup service to store backups in Ceph. This involves configuring the service to use Ceph Object Storage (assuming you are also deploying the Ceph Object Gateway, as in Section 2.8, “Deploy the Ceph Object Gateway”). To do so, add the following line to the parameter_defaults of your environment file:

CinderBackupBackend: swift

CinderBackupBackend: ceph

The Ceph Storage OSDs and journal partitions require GPT disk labels. This means the additional disks on Ceph Storage require conversion to GPT labels before installing the Ceph OSD. To accomplish this, the node must execute a script to perform this operation on first boot. You include this script as part of a Heat template in your Overcloud creation. For example, the following heat template (wipe-disks.yaml) runs a script that checks all disks on Ceph Storage node and converts all of them (except the disk containing the root file system) to GPT.

heat_template_version: 2014-10-16

description: >
  Wipe and convert all disks to GPT (except the disk containing the root file system)

resources:
  userdata:
    type: OS::Heat::MultipartMime
    properties:
      parts:
      - config: {get_resource: wipe_disk}

  wipe_disk:
    type: OS::Heat::SoftwareConfig
    properties:
      config: {get_file: wipe-disk.sh}

outputs:
  OS::stack_id:
    value: {get_resource: userdata}

This Heat template makes reference to a Bash script called wipe-disk.sh. This script contains your procedure to wipe the non-root disks. The following script is an example of wipe-disk.sh that wipes all disks except for the root disk:

#!/bin/bash
if [[ `hostname` = *"ceph"* ]]
then
  echo "Number of disks detected: $(lsblk -no NAME,TYPE,MOUNTPOINT | grep "disk" | awk '{print $1}' | wc -l)"
  for DEVICE in `lsblk -no NAME,TYPE,MOUNTPOINT | grep "disk" | awk '{print $1}'`
  do
    ROOTFOUND=0
    echo "Checking /dev/$DEVICE..."
    echo "Number of partitions on /dev/$DEVICE: $(expr $(lsblk -n /dev/$DEVICE | awk '{print $7}' | wc -l) - 1)"
    for MOUNTS in `lsblk -n /dev/$DEVICE | awk '{print $7}'`
    do
      if [ "$MOUNTS" = "/" ]
      then
        ROOTFOUND=1
      fi
    done
    if [ $ROOTFOUND = 0 ]
    then
      echo "Root not found in /dev/${DEVICE}"
      echo "Wiping disk /dev/${DEVICE}"
      sgdisk -Z /dev/${DEVICE}
      sgdisk -g /dev/${DEVICE}
    else
      echo "Root found in /dev/${DEVICE}"
    fi
  done
fi

To include the Heat template in your environment, register it as the NodeUserData resource in your storage-environment.yaml file:

resource_registry:
  OS::TripleO::NodeUserData: /home/stack/templates/firstboot/wipe-disks.yaml

Using a bonded interface allows you to combine multiple NICs to add redundancy to a network connection. If you have enough NICs on your Ceph nodes, you can take this a step further by creating multiple bonded interfaces per node.

With this, you can then use a bonded interface for each network connection required by the node. This provides both redundancy and a dedicated connection for each network.

The simplest implementation of this involves the use of two bonds, one for each storage network used by the Ceph nodes. These networks are the following:

Configuring this involves customizing a network interface template, as the director does not provide any sample templates that deploy multiple bonded NICs. However, the director does provide a template that deploys a single bonded interface — namely, /usr/share/openstack-tripleo-heat-templates/network/config/bond-with-vlans/ceph-storage.yaml. You can add a bonded interface for your additional NICs by defining it there.

The following snippet contains the default definition for the single bonded interface defined by /usr/share/openstack-tripleo-heat-templates/network/config/bond-with-vlans/ceph-storage.yaml:

  type: ovs_bridge // 1
  name: br-bond
  members:
    -
      type: ovs_bond // 2
      name: bond1 // 3
      ovs_options: {get_param: BondInterfaceOvsOptions} 4
      members: // 5
        -
          type: interface
          name: nic2
          primary: true
        -
          type: interface
          name: nic3
    -
      type: vlan // 6
      device: bond1 // 7
      vlan_id: {get_param: StorageNetworkVlanID}
      addresses:
        -
          ip_netmask: {get_param: StorageIpSubnet}
    -
      type: vlan
      device: bond1
      vlan_id: {get_param: StorageMgmtNetworkVlanID}
      addresses:
        -
          ip_netmask: {get_param: StorageMgmtIpSubnet}

With at least two more NICs, you can define an additional bridge and bonded interface. Then, you can move one of the VLANs to the new bonded interface. This results in added throughput and reliability for both storage network connections.

When customizing /usr/share/openstack-tripleo-heat-templates/network/config/bond-with-vlans/ceph-storage.yaml for this purpose, it is advisable to also use Linux bonds (type: linux_bond ) instead of the default OVS (type: ovs_bond). This bond type is more suitable for enterprise production deployments.

The following edited snippet defines an additional OVS bridge (br-bond2) which houses a new Linux bond named bond2. The bond2 interface uses two additional NICs (namely, nic4 and nic5) and will be used solely for back-end storage network traffic:

  type: ovs_bridge
  name: br-bond
  members:
    -
      type: linux_bond
      name: bond1
      bonding_options: {get_param: BondInterfaceOvsOptions} // 1
      members:
        -
          type: interface
          name: nic2
          primary: true
        -
          type: interface
          name: nic3
    -
      type: vlan
      device: bond1
      vlan_id: {get_param: StorageNetworkVlanID}
      addresses:
        -
          ip_netmask: {get_param: StorageIpSubnet}
-
  type: ovs_bridge
  name: br-bond2
  members:
    -
      type: linux_bond
      name: bond2
      bonding_options: {get_param: BondInterfaceOvsOptions}
      members:
        -
          type: interface
          name: nic4
          primary: true
        -
          type: interface
          name: nic5
    -
      type: vlan
      device: bond1
      vlan_id: {get_param: StorageMgmtNetworkVlanID}
      addresses:
        -
          ip_netmask: {get_param: StorageMgmtIpSubnet}

For the full contents of this customized template, see Appendix B, Sample Custom Interface Template: Multiple Bonded Interfaces.

BondInterfaceOvsOptions:
    default: ''
    description: The ovs_options string for the bond interface. Set
                 things like lacp=active and/or bond_mode=balance-slb
                 using this option.
    type: string

BondInterfaceOvsOptions:
    default: 'mode=4 lacp_rate=1'
    description: The bonding_options string for the bond interface. Set
                 things like lacp=active and/or bond_mode=balance-slb
                 using this option.
    type: string

It is possible to override the default configuration parameters for Ceph Storage nodes using the ExtraConfig hook to define data to pass to the Puppet configuration. There are two methods to pass this data:

parameter_defaults:
  ExtraConfig:
    ceph::profile::params::osd_journal_size: 2048

Add this content to an environment file (for example, ceph-settings.yaml) and include it when you run the openstack overcloud deploy command in Section 2.13, “Creating the Overcloud”. For example:

$ openstack overcloud deploy --templates --ceph-storage-scale <number of nodes> -e /home/stack/templates/storage-environment.yaml -e /home/stack/templates/ceph-settings.yaml

parameter_defaults:
  ExtraConfig:
    ceph::conf::args:
      global/max_open_files:
        value: 131072

Add this content to an environment file (for example, ceph-settings.yaml) and include it when you run the openstack overcloud deploy command in Section 2.13, “Creating the Overcloud”. For example:

$ openstack overcloud deploy --templates --ceph-storage-scale <number of nodes> -e /home/stack/templates/storage-environment.yaml -e /home/stack/templates/ceph-settings.yaml

The resulting ceph.conf file should be populated with the following:

[global]
max_open_files = 131072

parameter_defaults:
  CephPools:
    POOL:
      size: 5
      pg_num: 128
      pgp_num: 128

The creation of the Overcloud requires additional arguments for the openstack overcloud deploy command. For example:

$ openstack overcloud deploy --templates -e /home/stack/templates/storage-environment.yaml --control-scale 3 --compute-scale 3 --ceph-storage-scale 3 --control-flavor control --compute-flavor compute --ceph-storage-flavor ceph-storage --ntp-server pool.ntp.org

The above command uses the following options:

See Appendix A, Sample Environment File: Creating a Ceph Cluster for an overview of all the settings used in /home/stack/templates/storage-environment.yaml.

$ openstack help overcloud deploy

The Overcloud creation process begins and the director provisions your nodes. This process takes some time to complete. To view the status of the Overcloud creation, open a separate terminal as the stack user and run:

$ source ~/stackrc
$ heat stack-list --show-nested

The director generates a script to configure and help authenticate interactions with your Overcloud from the director host. The director saves this file (overcloudrc) in your stack user’s home directory. Run the following command to use this file:

$ source ~/overcloudrc

This loads the necessary environment variables to interact with your Overcloud from the director host’s CLI. To return to interacting with the director’s host, run the following command:

$ source ~/stackrc

After completing the Overcloud creation, it is recommended to check the status of the Ceph Storage Cluster to make sure it is working properly. To accomplish this, log into a Controller node as the heat-admin user from the director.

$ nova list
$ ssh heat-admin@192.168.0.25

Check the health of the cluster:

$ sudo ceph health

If the cluster has no issues, the command reports back HEALTH_OK. This means the cluster is safe to use.

Check the status of the Ceph Monitor quorum:

$ sudo ceph quorum_status

This shows the monitors participating in the quorum and which one is the leader.

Check if all Ceph OSDs are running:

$ ceph osd stat

For more information on monitoring Ceph Storage clusters, see Monitoring in the Red Hat Ceph Storage Administration Guide.

A situation might occur where you need to reboot the environment. For example, when you might need to modify the physical servers, or you might need to recover from a power outage. In this situation, it is important to make sure your Ceph Storage nodes boot correctly.

Make sure to boot the nodes in the following order:

Use the following process to reboot the Ceph Storage nodes:

If a situation occurs where all Overcloud nodes boot at the same time, the Ceph OSD services might not start correctly on the Ceph Storage nodes. In this situation, reboot the Ceph Storage OSDs so they can connect to the Ceph Monitor service. Run the following command on each Ceph Storage node:

$ sudo systemctl restart 'ceph*'

Verify a HEALTH_OK status of the Ceph Storage node cluster with the following command:

$ sudo ceph status

If a Ceph Storage node fails, you must disable and rebalance the faulty node before removing it from the overcloud to prevent data loss. This procedure explains the process for replacing a Ceph Storage node.

Log in to either a Controller node or a Ceph Storage node as the heat-admin user. The director’s stack user has an SSH key to access the heat-admin user.

List the OSD tree and find the OSDs for your node. For example, the node to remove might contain the following OSDs:

-2 0.09998        host overcloud-cephstorage-0
0 0.04999         osd.0                         up  1.00000          1.00000
1 0.04999         osd.1                         up  1.00000          1.00000

Disable the OSDs on the Ceph Storage node. In this case, the OSD IDs are 0 and 1.

[heat-admin@overcloud-controller-0 ~]$ sudo ceph osd out 0
[heat-admin@overcloud-controller-0 ~]$ sudo ceph osd out 1

The Ceph Storage cluster begins rebalancing. Wait for this process to complete. You can monitor the status using the following command:

[heat-admin@overcloud-controller-0 ~]$ sudo ceph -w

After the Ceph cluster finishes rebalancing, log in to the faulty Ceph Storage node as the heat-admin user and stop the node.

[heat-admin@overcloud-cephstorage-0 ~]$ systemctl stop ceph-osd@0.service
[heat-admin@overcloud-cephstorage-0 ~]$ systemctl stop ceph-osd@1.service

Prevent the OSDs from starting during the next reboot.

[heat-admin@overcloud-cephstorage-0 ~]$ systemctl disable ceph-osd@0.service

[heat-admin@overcloud-cephstorage-0 ~]$ systemctl disable ceph-osd@1.service

Remove the Ceph Storage node from the CRUSH map so that it no longer receives data.

[heat-admin@overcloud-cephstorage-0 ~]$ sudo ceph osd crush remove osd.0
[heat-admin@overcloud-cephstorage-0 ~]$ sudo ceph osd crush remove osd.1

Remove the OSD authentication key.

[heat-admin@overcloud-cephstorage-0 ~]$ sudo ceph auth del osd.0
[heat-admin@overcloud-cephstorage-0 ~]$ sudo ceph auth del osd.1

Remove the OSD from the cluster.

[heat-admin@overcloud-cephstorage-0 ~]$ sudo ceph osd rm 0
[heat-admin@overcloud-cephstorage-0 ~]$ sudo ceph osd rm 1

Leave the node and return to the director host as the stack user.

[heat-admin@overcloud-cephstorage-0 ~]$ exit
[stack@director ~]$

Disable the Ceph Storage node so the director does not reprovision it.

[stack@director ~]$ ironic node-list
[stack@director ~]$ ironic node-set-maintenance [UUID] true

Removing a Ceph Storage node requires an update to the overcloud stack in the director using the local template files. First, identify the UUID of the Overcloud stack.

$ heat stack-list

Identify the UUIDs of the Ceph Storage node to delete.

$ nova list

Run the following command to delete the node from the stack and update the plan accordingly.

$ openstack overcloud node delete --stack [STACK_UUID] --templates -e [ENVIRONMENT_FILE] [NODE_UUID]

Wait until the stack completes its update. Monitor the stack update using the heat stack-list --show-nested command.

Add new nodes to the director’s node pool and deploy them as Ceph Storage nodes. Use the --ceph-storage-scale option to define the total number of Ceph Storage nodes in the overcloud. For example, if you removed a faulty node from a three-node cluster and you want to replace it, use --ceph-storage-scale 3 to return the number of Ceph Storage nodes to its original value.

$ openstack overcloud deploy --templates --ceph-storage-scale 3 -e [ENVIRONMENT_FILES]

The director provisions the new node and updates the entire stack with the new node’s details.

Log in to a Controller node as the heat-admin user and check the status of the Ceph Storage node.

[heat-admin@overcloud-controller-0 ~]$ sudo ceph status

Confirm that the value in the osdmap section matches the number of desired nodes in your cluster.

The failed Ceph Storage node has now been replaced with a new node.

In situations when an OSD disk fails and requires a replacement, use the standard instructions from the Red Hat Ceph Storage Administration Guide: