ceph-deploy – Ceph deployment tool
Synopsis
ceph-deploy**new** [initial-monitor-node(s)]
ceph-deploy**install** [ceph-node] [ceph-node…]
ceph-deploy**mon**create-initial
ceph-deploy**osd**create–datadevice__ceph-node
ceph-deploy**admin** [admin-node][ceph-node…]
ceph-deploy**purgedata** [ceph-node][ceph-node…]
ceph-deploy**forgetkeys**
Description
ceph-deploy is a tool which allows easy and quick deployment of aCeph cluster without involving complex and detailed manual configuration. Ituses ssh to gain access to other Ceph nodes from the admin node, sudo foradministrator privileges on them and the underlying Python scripts automatesthe manual process of Ceph installation on each node from the admin node itself.It can be easily run on an workstation and doesn’t require servers, databases orany other automated tools. With ceph-deploy, it is really easy to setup and take down a cluster. However, it is not a generic deployment tool. It isa specific tool which is designed for those who want to get Ceph up and runningquickly with only the unavoidable initial configuration settings and without theoverhead of installing other tools like Chef
, Puppet
or Juju
. Thosewho want to customize security settings, partitions or directory locations andwant to set up a cluster following detailed manual steps, should use other toolsi.e, Chef
, Puppet
, Juju
or Crowbar
.
With ceph-deploy, you can install Ceph packages on remote nodes,create a cluster, add monitors, gather/forget keys, add OSDs and metadataservers, configure admin hosts or take down the cluster.
Commands
new
Start deploying a new cluster and write a configuration file and keyring for it.It tries to copy ssh keys from admin node to gain passwordless ssh to monitornode(s), validates host IP, creates a cluster with a new initial monitor node ornodes for monitor quorum, a ceph configuration file, a monitor secret keyring anda log file for the new cluster. It populates the newly created Ceph configurationfile with fsid
of cluster, hostnames and IP addresses of initial monitormembers under [global]
section.
Usage:
- ceph-deploy new [MON][MON...]
Here, [MON] is the initial monitor hostname (short hostname i.e, hostname -s
).
Other options like —no-ssh-copykey
, —fsid
,—cluster-network
and —public-network
can also be used withthis command.
If more than one network interface is used, public network
setting has to beadded under [global]
section of Ceph configuration file. If the public subnetis given, new
command will choose the one IP from the remote host that existswithin the subnet range. Public network can also be added at runtime using—public-network
option with the command as mentioned above.
install
Install Ceph packages on remote hosts. As a first step it installsyum-plugin-priorities
in admin and other nodes using passwordless ssh and sudoso that Ceph packages from upstream repository get more priority. It then detectsthe platform and distribution for the hosts and installs Ceph normally bydownloading distro compatible packages if adequate repo for Ceph is already added.—release
flag is used to get the latest release for installation. Duringdetection of platform and distribution before installation, if it finds thedistro.init
to be sysvinit
(Fedora, CentOS/RHEL etc), it doesn’t allowinstallation with custom cluster name and uses the default name ceph
for thecluster.
If the user explicitly specifies a custom repo url with —repo-url
forinstallation, anything detected from the configuration will be overridden andthe custom repository location will be used for installation of Ceph packages.If required, valid custom repositories are also detected and installed. In caseof installation from a custom repo a boolean is used to determine the logicneeded to proceed with a custom repo installation. A custom repo install helperis used that goes through config checks to retrieve repos (and any extra reposdefined) and installs them. cd_conf
is the object built from argparse
that holds the flags and information needed to determine what metadata from theconfiguration is to be used.
A user can also opt to install only the repository without installing Ceph andits dependencies by using —repo
option.
Usage:
- ceph-deploy install [HOST][HOST...]
Here, [HOST] is/are the host node(s) where Ceph is to be installed.
An option —release
is used to install a release known as CODENAME(default: firefly).
Other options like —testing
, —dev
, —adjust-repos
,—no-adjust-repos
, —repo
, —local-mirror
,—repo-url
and —gpg-url
can also be used with this command.
mds
Deploy Ceph mds on remote hosts. A metadata server is needed to use CephFS andthe mds
command is used to create one on the desired host node. It uses thesubcommand create
to do so. create
first gets the hostname and distroinformation of the desired mds host. It then tries to read the bootstrap-mds
key for the cluster and deploy it in the desired host. The key generally has aformat of {cluster}.bootstrap-mds.keyring
. If it doesn’t finds a keyring,it runs gatherkeys
to get the keyring. It then creates a mds on the desiredhost under the path /var/lib/ceph/mds/
in /var/lib/ceph/mds/{cluster}-{name}
format and a bootstrap keyring under /var/lib/ceph/bootstrap-mds/
in/var/lib/ceph/bootstrap-mds/{cluster}.keyring
format. It then runs appropriatecommands based on distro.init
to start the mds
.
Usage:
- ceph-deploy mds create [HOST[:DAEMON-NAME]] [HOST[:DAEMON-NAME]...]
The [DAEMON-NAME] is optional.
mon
Deploy Ceph monitor on remote hosts. mon
makes use of certain subcommandsto deploy Ceph monitors on other nodes.
Subcommand create-initial
deploys for monitors defined inmon initial members
under [global]
section in Ceph configuration file,wait until they form quorum and then gatherkeys, reporting the monitor statusalong the process. If monitors don’t form quorum the command will eventuallytime out.
Usage:
- ceph-deploy mon create-initial
Subcommand create
is used to deploy Ceph monitors by explicitly specifyingthe hosts which are desired to be made monitors. If no hosts are specified itwill default to use the mon initial members
defined under [global]
section of Ceph configuration file. create
first detects platform and distrofor desired hosts and checks if hostname is compatible for deployment. It thenuses the monitor keyring initially created using new
command and deploys themonitor in desired host. If multiple hosts were specified during new
commandi.e, if there are multiple hosts in mon initial members
and multiple keyringswere created then a concatenated keyring is used for deployment of monitors. Inthis process a keyring parser is used which looks for [entity]
sections inmonitor keyrings and returns a list of those sections. A helper is then used tocollect all keyrings into a single blob that will be used to inject it to monitorswith —mkfs
on remote nodes. All keyring files are concatenated to bein a directory ending with .keyring
. During this process the helper uses listof sections returned by keyring parser to check if an entity is already presentin a keyring and if not, adds it. The concatenated keyring is used for deploymentof monitors to desired multiple hosts.
Usage:
- ceph-deploy mon create [HOST] [HOST...]
Here, [HOST] is hostname of desired monitor host(s).
Subcommand add
is used to add a monitor to an existing cluster. It firstdetects platform and distro for desired host and checks if hostname is compatiblefor deployment. It then uses the monitor keyring, ensures configuration for newmonitor host and adds the monitor to the cluster. If the section for the monitorexists and defines a monitor address that will be used, otherwise it will fallback byresolving the hostname to an IP. If —address
is used it will overrideall other options. After adding the monitor to the cluster, it gives it some timeto start. It then looks for any monitor errors and checks monitor status. Monitorerrors arise if the monitor is not added in mon initial members
, if it doesn’texist in monmap
and if neither public_addr
nor public_network
keyswere defined for monitors. Under such conditions, monitors may not be able toform quorum. Monitor status tells if the monitor is up and running normally. Thestatus is checked by running ceph daemon mon.hostname mon_status
on remoteend which provides the output and returns a boolean status of what is going on.False
means a monitor that is not fine even if it is up and running, whileTrue
means the monitor is up and running correctly.
Usage:
- ceph-deploy mon add [HOST]
- ceph-deploy mon add [HOST] --address [IP]
Here, [HOST] is the hostname and [IP] is the IP address of the desired monitornode. Please note, unlike other mon
subcommands, only one node can bespecified at a time.
Subcommand destroy
is used to completely remove monitors on remote hosts.It takes hostnames as arguments. It stops the monitor, verifies if ceph-mon
daemon really stopped, creates an archive directory mon-remove
under/var/lib/ceph/
, archives old monitor directory in{cluster}-{hostname}-{stamp}
format in it and removes the monitor fromcluster by running ceph remove…
command.
Usage:
- ceph-deploy mon destroy [HOST] [HOST...]
Here, [HOST] is hostname of monitor that is to be removed.
gatherkeys
Gather authentication keys for provisioning new nodes. It takes hostnames asarguments. It checks for and fetches client.admin
keyring, monitor keyringand bootstrap-mds/bootstrap-osd
keyring from monitor host. Theseauthentication keys are used when new monitors/OSDs/MDS
are added to thecluster.
Usage:
- ceph-deploy gatherkeys [HOST] [HOST...]
Here, [HOST] is hostname of the monitor from where keys are to be pulled.
disk
Manage disks on a remote host. It actually triggers the ceph-volume
utilityand its subcommands to manage disks.
Subcommand list
lists disk partitions and Ceph OSDs.
Usage:
- ceph-deploy disk list HOST
Subcommand zap
zaps/erases/destroys a device’s partition table andcontents. It actually uses ceph-volume lvm zap
remotely, alternativelyallowing someone to remove the Ceph metadata from the logical volume.
osd
Manage OSDs by preparing data disk on remote host. osd
makes use of certainsubcommands for managing OSDs.
Subcommand create
prepares a device for Ceph OSD. It first checks againstmultiple OSDs getting created and warns about the possibility of more than therecommended which would cause issues with max allowed PIDs in a system. It thenreads the bootstrap-osd key for the cluster or writes the bootstrap key if notfound.It then uses ceph-volume utility’s lvm create
subcommand toprepare the disk, (and journal if using filestore) and deploy the OSD on the desired host.Once prepared, it gives some time to the OSD to start and checks for anypossible errors and if found, reports to the user.
Bluestore Usage:
- ceph-deploy osd create --data DISK HOST
Filestore Usage:
- ceph-deploy osd create --data DISK --journal JOURNAL HOST
Note
For other flags available, please see the man page or the –help menuon ceph-deploy osd create
Subcommand list
lists devices associated to Ceph as part of an OSD.It uses the ceph-volume lvm list
output that has a rich output, mappingOSDs to devices and other interesting information about the OSD setup.
Usage:
- ceph-deploy osd list HOST
admin
Push configuration and client.admin
key to a remote host. It takesthe {cluster}.client.admin.keyring
from admin node and writes it under/etc/ceph
directory of desired node.
Usage:
- ceph-deploy admin [HOST] [HOST...]
Here, [HOST] is desired host to be configured for Ceph administration.
config
Push/pull configuration file to/from a remote host. It uses push
subcommandto takes the configuration file from admin host and write it to remote host under/etc/ceph
directory. It uses pull
subcommand to do the opposite i.e, pullthe configuration file under /etc/ceph
directory of remote host to admin node.
Usage:
- ceph-deploy config push [HOST] [HOST...]
- ceph-deploy config pull [HOST] [HOST...]
Here, [HOST] is the hostname of the node where config file will be pushed to orpulled from.
uninstall
Remove Ceph packages from remote hosts. It detects the platform and distro ofselected host and uninstalls Ceph packages from it. However, some dependencieslike librbd1
and librados2
will not be removed because they can causeissues with qemu-kvm
.
Usage:
- ceph-deploy uninstall [HOST] [HOST...]
Here, [HOST] is hostname of the node from where Ceph will be uninstalled.
purge
Remove Ceph packages from remote hosts and purge all data. It detects theplatform and distro of selected host, uninstalls Ceph packages and purges alldata. However, some dependencies like librbd1
and librados2
will not beremoved because they can cause issues with qemu-kvm
.
Usage:
- ceph-deploy purge [HOST] [HOST...]
Here, [HOST] is hostname of the node from where Ceph will be purged.
purgedata
Purge (delete, destroy, discard, shred) any Ceph data from /var/lib/ceph
.Once it detects the platform and distro of desired host, it first checks if Cephis still installed on the selected host and if installed, it won’t purge datafrom it. If Ceph is already uninstalled from the host, it tries to remove thecontents of /var/lib/ceph
. If it fails then probably OSDs are still mountedand needs to be unmounted to continue. It unmount the OSDs and tries to removethe contents of /var/lib/ceph
again and checks for errors. It also removescontents of /etc/ceph
. Once all steps are successfully completed, all theCeph data from the selected host are removed.
Usage:
- ceph-deploy purgedata [HOST] [HOST...]
Here, [HOST] is hostname of the node from where Ceph data will be purged.
forgetkeys
Remove authentication keys from the local directory. It removes all theauthentication keys i.e, monitor keyring, client.admin keyring, bootstrap-osdand bootstrap-mds keyring from the node.
Usage:
- ceph-deploy forgetkeys
pkg
Manage packages on remote hosts. It is used for installing or removing packagesfrom remote hosts. The package names for installation or removal are to bespecified after the command. Two options —install
and—remove
are used for this purpose.
Usage:
- ceph-deploy pkg --install [PKGs] [HOST] [HOST...]
- ceph-deploy pkg --remove [PKGs] [HOST] [HOST...]
Here, [PKGs] is comma-separated package names and [HOST] is hostname of theremote node where packages are to be installed or removed from.
Options
—fs-type
- Filesystem to use to format disk
(xfs, btrfs or ext4)
. Note that support for btrfs and ext4 is no longer tested or recommended; please use xfs.
Availability
ceph-deploy is part of Ceph, a massively scalable, open-source, distributed storage system. Please refer tothe documentation at https://ceph.com/ceph-deploy/docs for more information.
See also
ceph-mon(8),ceph-osd(8),ceph-volume(8),ceph-mds(8)