Manual Deployment on FreeBSD

This a largely a copy of the regular Manual Deployment with FreeBSD specifics. The difference lies in two parts: The underlying diskformat, and the way to use the tools.

All Ceph clusters require at least one monitor, and at least as many OSDs as copies of an object stored on the cluster. Bootstrapping the initial monitor(s) is the first step in deploying a Ceph Storage Cluster. Monitor deployment also sets important criteria for the entire cluster, such as the number of replicas for pools, the number of placement groups per OSD, the heartbeat intervals, whether authentication is required, etc. Most of these values are set by default, so it’s useful to know about them when setting up your cluster for production.

We will set up a cluster with node1 as the monitor node, and node2 and node3 for OSD nodes.

Disklayout on FreeBSD

Current implementation works on ZFS pools

  • All Ceph data is created in /var/lib/ceph

  • Log files go into /var/log/ceph

  • PID files go into /var/log/run

  • One ZFS pool is allocated per OSD, like:

    gpart create -s GPT ada1
    gpart add -t freebsd-zfs -l osd.1 ada1
    zpool create -m /var/lib/ceph/osd/osd.1 osd.1 gpt/osd.1
    
  • Some cache and log (ZIL) can be attached. Please note that this is different from the Ceph journals. Cache and log are totally transparent for Ceph, and help the file system to keep the system consistent and help performance. Assuming that ada2 is an SSD:

    gpart create -s GPT ada2
    gpart add -t freebsd-zfs -l osd.1-log -s 1G ada2
    zpool add osd.1 log gpt/osd.1-log
    gpart add -t freebsd-zfs -l osd.1-cache -s 10G ada2
    zpool add osd.1 log gpt/osd.1-cache
    
  • Note: UFS2 does not allow large xattribs

Configuration

As per FreeBSD default parts of extra software go into /usr/local/. Which means that for /etc/ceph.conf the default location is /usr/local/etc/ceph/ceph.conf. Smartest thing to do is to create a softlink from /etc/ceph to /usr/local/etc/ceph:

ln -s /usr/local/etc/ceph /etc/ceph

A sample file is provided in /usr/local/share/doc/ceph/sample.ceph.conf Note that /usr/local/etc/ceph/ceph.conf will be found by most tools, linking it to /etc/ceph/ceph.conf will help with any scripts that are found in extra tools, scripts, and/or discussionlists.

Monitor Bootstrapping

Bootstrapping a monitor (a Ceph Storage Cluster, in theory) requires a number of things:

  • Unique Identifier: The fsid is a unique identifier for the cluster, and stands for File System ID from the days when the Ceph Storage Cluster was principally for the Ceph File System. Ceph now supports native interfaces, block devices, and object storage gateway interfaces too, so fsid is a bit of a misnomer.

  • Cluster Name: Ceph clusters have a cluster name, which is a simple string without spaces. The default cluster name is ceph, but you may specify a different cluster name. Overriding the default cluster name is especially useful when you are working with multiple clusters and you need to clearly understand which cluster your are working with.

    For example, when you run multiple clusters in a multisite configuration, the cluster name (e.g., us-west, us-east) identifies the cluster for the current CLI session. Note: To identify the cluster name on the command line interface, specify the a Ceph configuration file with the cluster name (e.g., ceph.conf, us-west.conf, us-east.conf, etc.). Also see CLI usage (ceph --cluster {cluster-name}).

  • Monitor Name: Each monitor instance within a cluster has a unique name. In common practice, the Ceph Monitor name is the host name (we recommend one Ceph Monitor per host, and no commingling of Ceph OSD Daemons with Ceph Monitors). You may retrieve the short hostname with hostname -s.

  • Monitor Map: Bootstrapping the initial monitor(s) requires you to generate a monitor map. The monitor map requires the fsid, the cluster name (or uses the default), and at least one host name and its IP address.

  • Monitor Keyring: Monitors communicate with each other via a secret key. You must generate a keyring with a monitor secret and provide it when bootstrapping the initial monitor(s).

  • Administrator Keyring: To use the ceph CLI tools, you must have a client.admin user. So you must generate the admin user and keyring, and you must also add the client.admin user to the monitor keyring.

The foregoing requirements do not imply the creation of a Ceph Configuration file. However, as a best practice, we recommend creating a Ceph configuration file and populating it with the fsid, the mon initial members and the mon host settings.

You can get and set all of the monitor settings at runtime as well. However, a Ceph Configuration file may contain only those settings that override the default values. When you add settings to a Ceph configuration file, these settings override the default settings. Maintaining those settings in a Ceph configuration file makes it easier to maintain your cluster.

The procedure is as follows:

  1. Log in to the initial monitor node(s):

    ssh {hostname}
    

    For example:

    ssh node1
    
  2. Ensure you have a directory for the Ceph configuration file. By default, Ceph uses /etc/ceph. When you install ceph, the installer will create the /etc/ceph directory automatically.

    ls /etc/ceph
    
  3. Create a Ceph configuration file. By default, Ceph uses ceph.conf, where ceph reflects the cluster name.

    sudo vim /etc/ceph/ceph.conf
    
  4. Generate a unique ID (i.e., fsid) for your cluster.

    uuidgen
    
  5. Add the unique ID to your Ceph configuration file.

    fsid = {UUID}
    

    For example:

    fsid = a7f64266-0894-4f1e-a635-d0aeaca0e993
    
  6. Add the initial monitor(s) to your Ceph configuration file.

    mon initial members = {hostname}[,{hostname}]
    

    For example:

    mon initial members = node1
    
  7. Add the IP address(es) of the initial monitor(s) to your Ceph configuration file and save the file.

    mon host = {ip-address}[,{ip-address}]
    

    For example:

    mon host = 192.168.0.1
    

    Note: You may use IPv6 addresses instead of IPv4 addresses, but you must set ms bind ipv6 to true. See Network Configuration Reference for details about network configuration.

  8. Create a keyring for your cluster and generate a monitor secret key.

    ceph-authtool --create-keyring /tmp/ceph.mon.keyring --gen-key -n mon. --cap mon 'allow *'
    
  9. Generate an administrator keyring, generate a client.admin user and add the user to the keyring.

    sudo ceph-authtool --create-keyring /etc/ceph/ceph.client.admin.keyring --gen-key -n client.admin --cap mon 'allow *' --cap osd 'allow *' --cap mds 'allow *' --cap mgr 'allow *'
    
  10. Add the client.admin key to the ceph.mon.keyring.

    ceph-authtool /tmp/ceph.mon.keyring --import-keyring /etc/ceph/ceph.client.admin.keyring
    
  11. Generate a monitor map using the hostname(s), host IP address(es) and the FSID. Save it as /tmp/monmap:

    monmaptool --create --add {hostname} {ip-address} --fsid {uuid} /tmp/monmap
    

    For example:

    monmaptool --create --add node1 192.168.0.1 --fsid a7f64266-0894-4f1e-a635-d0aeaca0e993 /tmp/monmap
    
  12. Create a default data directory (or directories) on the monitor host(s).

    sudo mkdir /var/lib/ceph/mon/{cluster-name}-{hostname}
    

    For example:

    sudo mkdir /var/lib/ceph/mon/ceph-node1
    

    See Monitor Config Reference - Data for details.

  13. Populate the monitor daemon(s) with the monitor map and keyring.

    sudo -u ceph ceph-mon [--cluster {cluster-name}] --mkfs -i {hostname} --monmap /tmp/monmap --keyring /tmp/ceph.mon.keyring
    

    For example:

    sudo -u ceph ceph-mon --mkfs -i node1 --monmap /tmp/monmap --keyring /tmp/ceph.mon.keyring
    
  14. Consider settings for a Ceph configuration file. Common settings include the following:

    [global]
    fsid = {cluster-id}
    mon initial members = {hostname}[, {hostname}]
    mon host = {ip-address}[, {ip-address}]
    public network = {network}[, {network}]
    cluster network = {network}[, {network}]
    auth cluster required = cephx
    auth service required = cephx
    auth client required = cephx
    osd journal size = {n}
    osd pool default size = {n}  # Write an object n times.
    osd pool default min size = {n} # Allow writing n copy in a degraded state.
    osd pool default pg num = {n}
    osd pool default pgp num = {n}
    osd crush chooseleaf type = {n}
    

    In the foregoing example, the [global] section of the configuration might look like this:

    [global]
    fsid = a7f64266-0894-4f1e-a635-d0aeaca0e993
    mon initial members = node1
    mon host = 192.168.0.1
    public network = 192.168.0.0/24
    auth cluster required = cephx
    auth service required = cephx
    auth client required = cephx
    osd journal size = 1024
    osd pool default size = 3
    osd pool default min size = 2
    osd pool default pg num = 333
    osd pool default pgp num = 333
    osd crush chooseleaf type = 1
    
  15. Touch the done file.

    Mark that the monitor is created and ready to be started:

    sudo touch /var/lib/ceph/mon/ceph-node1/done
    
  16. And for FreeBSD an entry for every monitor needs to be added to the config file. (The requirement will be removed in future releases).

    The entry should look like:

    [mon]
        [mon.node1]
            host = node1    # this name can be resolve
    
  17. Start the monitor(s).

    For FreeBSD we use the rc.d init scripts (called bsdrc in Ceph):

    sudo service ceph start start mon.node1
    
    For this to work /etc/rc.conf also needs the entry to enable ceph::

    cat ‘ceph_enable=”YES”’ >> /etc/rc.conf

  18. Verify that Ceph created the default pools.

    ceph osd lspools
    

    You should see output like this:

    0 data
    1 metadata
    2 rbd
    
  19. Verify that the monitor is running.

    ceph -s
    

    You should see output that the monitor you started is up and running, and you should see a health error indicating that placement groups are stuck inactive. It should look something like this:

    cluster a7f64266-0894-4f1e-a635-d0aeaca0e993
      health HEALTH_ERR 192 pgs stuck inactive; 192 pgs stuck unclean; no osds
      monmap e1: 1 mons at {node1=192.168.0.1:6789/0}, election epoch 1, quorum 0 node1
      osdmap e1: 0 osds: 0 up, 0 in
      pgmap v2: 192 pgs, 3 pools, 0 bytes data, 0 objects
         0 kB used, 0 kB / 0 kB avail
         192 creating
    

    Note: Once you add OSDs and start them, the placement group health errors should disappear. See the next section for details.

Adding OSDs

Once you have your initial monitor(s) running, you should add OSDs. Your cluster cannot reach an active + clean state until you have enough OSDs to handle the number of copies of an object (e.g., osd pool default size = 2 requires at least two OSDs). After bootstrapping your monitor, your cluster has a default CRUSH map; however, the CRUSH map doesn’t have any Ceph OSD Daemons mapped to a Ceph Node.

Long Form

Without the benefit of any helper utilities, create an OSD and add it to the cluster and CRUSH map with the following procedure. To create the first two OSDs with the long form procedure, execute the following on node2 and node3:

  1. Connect to the OSD host.

    ssh {node-name}
    
  2. Generate a UUID for the OSD.

    uuidgen
    
  3. Create the OSD. If no UUID is given, it will be set automatically when the OSD starts up. The following command will output the OSD number, which you will need for subsequent steps.

    ceph osd create [{uuid} [{id}]]
    
  4. Create the default directory on your new OSD.

    ssh {new-osd-host}
    sudo mkdir /var/lib/ceph/osd/{cluster-name}-{osd-number}
    

    Above are the ZFS instructions to do this for FreeBSD.

  5. If the OSD is for a drive other than the OS drive, prepare it for use with Ceph, and mount it to the directory you just created.

  6. Initialize the OSD data directory.

    ssh {new-osd-host}
    sudo ceph-osd -i {osd-num} --mkfs --mkkey --osd-uuid [{uuid}]
    

    The directory must be empty before you can run ceph-osd with the --mkkey option. In addition, the ceph-osd tool requires specification of custom cluster names with the --cluster option.

  7. Register the OSD authentication key. The value of ceph for ceph-{osd-num} in the path is the $cluster-$id. If your cluster name differs from ceph, use your cluster name instead.:

    sudo ceph auth add osd.{osd-num} osd 'allow *' mon 'allow profile osd' -i /var/lib/ceph/osd/{cluster-name}-{osd-num}/keyring
    
  8. Add your Ceph Node to the CRUSH map.

    ceph [--cluster {cluster-name}] osd crush add-bucket {hostname} host
    

    For example:

    ceph osd crush add-bucket node1 host
    
  9. Place the Ceph Node under the root default.

    ceph osd crush move node1 root=default
    
  10. Add the OSD to the CRUSH map so that it can begin receiving data. You may also decompile the CRUSH map, add the OSD to the device list, add the host as a bucket (if it’s not already in the CRUSH map), add the device as an item in the host, assign it a weight, recompile it and set it.

    ceph [--cluster {cluster-name}] osd crush add {id-or-name} {weight} [{bucket-type}={bucket-name} ...]
    

    For example:

    ceph osd crush add osd.0 1.0 host=node1
    
  11. After you add an OSD to Ceph, the OSD is in your configuration. However, it is not yet running. The OSD is down and in. You must start your new OSD before it can begin receiving data.

    For FreeBSD using rc.d init.

    After adding the OSD to ceph.conf:

    sudo service ceph start osd.{osd-num}
    

    For example:

    sudo service ceph start osd.0
    sudo service ceph start osd.1
    

    In this case, to allow the start of the daemon at each reboot you must create an empty file like this:

    sudo touch /var/lib/ceph/osd/{cluster-name}-{osd-num}/bsdrc
    

    For example:

    sudo touch /var/lib/ceph/osd/ceph-0/bsdrc
    sudo touch /var/lib/ceph/osd/ceph-1/bsdrc
    

    Once you start your OSD, it is up and in.

Adding MDS

In the below instructions, {id} is an arbitrary name, such as the hostname of the machine.

  1. Create the mds data directory.:

    mkdir -p /var/lib/ceph/mds/{cluster-name}-{id}
    
  2. Create a keyring.:

    ceph-authtool --create-keyring /var/lib/ceph/mds/{cluster-name}-{id}/keyring --gen-key -n mds.{id}
    
  3. Import the keyring and set caps.:

    ceph auth add mds.{id} osd "allow rwx" mds "allow *" mon "allow profile mds" -i /var/lib/ceph/mds/{cluster}-{id}/keyring
    
  4. Add to ceph.conf.:

    [mds.{id}]
    host = {id}
    
  5. Start the daemon the manual way.:

    ceph-mds --cluster {cluster-name} -i {id} -m {mon-hostname}:{mon-port} [-f]
    
  6. Start the daemon the right way (using ceph.conf entry).:

    service ceph start
    
  7. If starting the daemon fails with this error:

    mds.-1.0 ERROR: failed to authenticate: (22) Invalid argument
    

    Then make sure you do not have a keyring set in ceph.conf in the global section; move it to the client section; or add a keyring setting specific to this mds daemon. And verify that you see the same key in the mds data directory and ceph auth get mds.{id} output.

  8. Now you are ready to create a Ceph file system.

Summary

Once you have your monitor and two OSDs up and running, you can watch the placement groups peer by executing the following:

ceph -w

To view the tree, execute the following:

ceph osd tree

You should see output that looks something like this:

# id    weight  type name       up/down reweight
-1      2       root default
-2      2               host node1
0       1                       osd.0   up      1
-3      1               host node2
1       1                       osd.1   up      1

To add (or remove) additional monitors, see Add/Remove Monitors. To add (or remove) additional Ceph OSD Daemons, see Add/Remove OSDs.