This document is for a development version of Ceph.
Have cephadm deploy and configure these services. This is the default when bootstrapping a new cluster unless the
--skip-monitoring-stackoption is used.
Deploy and configure these services manually. This is recommended for users with existing prometheus services in their environment (and in cases where Ceph is running in Kubernetes with Rook).
Skip the monitoring stack completely. Some Ceph dashboard graphs will not be available.
Prometheus’ security model presumes that untrusted users have access to the Prometheus HTTP endpoint and logs. Untrusted users have access to all the (meta)data Prometheus collects that is contained in the database, plus a variety of operational and debugging information.
However, Prometheus’ HTTP API is limited to read-only operations. Configurations can not be changed using the API and secrets are not exposed. Moreover, Prometheus has some built-in measures to mitigate the impact of denial of service attacks.
Please see Prometheus’ Security model <https://prometheus.io/docs/operating/security/> for more detailed information.
Deploying monitoring with cephadm¶
The default behavior of
cephadm is to deploy a basic monitoring stack. It
is however possible that you have a Ceph cluster without a monitoring stack,
and you would like to add a monitoring stack to it. (Here are some ways that
you might have come to have a Ceph cluster without a monitoring stack: You
might have passed the
--skip-monitoring stack option to
the installation of the cluster, or you might have converted an existing
cluster (which had no monitoring stack) to cephadm management.)
To set up monitoring on a Ceph cluster that has no monitoring, follow the steps below:
Enable the Prometheus module in the ceph-mgr daemon. This exposes the internal Ceph metrics so that Prometheus can scrape them:
ceph mgr module enable prometheus
Deploy a node-exporter service on every node of the cluster. The node-exporter provides host-level metrics like CPU and memory utilization:
ceph orch apply node-exporter '*'
ceph orch apply alertmanager 1
Deploy Prometheus. A single Prometheus instance is sufficient, but for high availablility (HA) you might want to deploy two:
ceph orch apply prometheus 1
ceph orch apply prometheus 2
ceph orch apply grafana 1
Manually setting the Grafana URL¶
Cephadm automatically configures Prometheus, Grafana, and Alertmanager in all cases except one.
In a some setups, the Dashboard user’s browser might not be able to access the Grafana URL that is configured in Ceph Dashboard. This can happen when the cluster and the accessing user are in different DNS zones.
If this is the case, you can use a configuration option for Ceph Dashboard to set the URL that the user’s browser will use to access Grafana. This value will never be altered by cephadm. To set this configuration option, issue the following command:
ceph dashboard set-grafana-frontend-api-url <grafana-server-api>
It might take a minute or two for services to be deployed. After the
services have been deployed, you should see something like this when you issue the command
ceph orch ls:
$ ceph orch ls NAME RUNNING REFRESHED IMAGE NAME IMAGE ID SPEC alertmanager 1/1 6s ago docker.io/prom/alertmanager:latest 0881eb8f169f present crash 2/2 6s ago docker.io/ceph/daemon-base:latest-master-devel mix present grafana 1/1 0s ago docker.io/pcuzner/ceph-grafana-el8:latest f77afcf0bcf6 absent node-exporter 2/2 6s ago docker.io/prom/node-exporter:latest e5a616e4b9cf present prometheus 1/1 6s ago docker.io/prom/prometheus:latest e935122ab143 present
Configuring SSL/TLS for Grafana¶
cephadm deploys Grafana using the certificate defined in the ceph
key/value store. If no certificate is specified,
cephadm generates a
self-signed certificate during the deployment of the Grafana service.
A custom certificate can be configured using the following commands:
ceph config-key set mgr/cephadm/grafana_key -i $PWD/key.pem ceph config-key set mgr/cephadm/grafana_crt -i $PWD/certificate.pem
If you have already deployed Grafana, run
reconfig on the service to
update its configuration:
ceph orch reconfig grafana
reconfig command also sets the proper URL for Ceph Dashboard.
Networks and Ports¶
All monitoring services can have the network and port they bind to configured with a yaml service specification
example spec file:
service_type: grafana service_name: grafana placement: count: 1 networks: - 220.127.116.11/24 spec: port: 4200
Using custom images¶
It is possible to install or upgrade monitoring components based on other images. To do so, the name of the image to be used needs to be stored in the configuration first. The following configuration options are available.
Custom images can be set with the
ceph config command
ceph config set mgr mgr/cephadm/<option_name> <value>
ceph config set mgr mgr/cephadm/container_image_prometheus prom/prometheus:v1.4.1
If there were already running monitoring stack daemon(s) of the type whose image you’ve changed, you must redeploy the daemon(s) in order to have them actually use the new image.
For example, if you had changed the prometheus image
ceph orch redeploy prometheus
By setting a custom image, the default value will be overridden (but not overwritten). The default value changes when updates become available. By setting a custom image, you will not be able to update the component you have set the custom image for automatically. You will need to manually update the configuration (image name and tag) to be able to install updates.
If you choose to go with the recommendations instead, you can reset the
custom image you have set before. After that, the default value will be
used again. Use
ceph config rm to reset the configuration option
ceph config rm mgr mgr/cephadm/<option_name>
ceph config rm mgr mgr/cephadm/container_image_prometheus
Using custom configuration files¶
By overriding cephadm templates, it is possible to completely customize the configuration files for monitoring services.
Internally, cephadm already uses Jinja2 templates to generate the configuration files for all monitoring components. To be able to customize the configuration of Prometheus, Grafana or the Alertmanager it is possible to store a Jinja2 template for each service that will be used for configuration generation instead. This template will be evaluated every time a service of that kind is deployed or reconfigured. That way, the custom configuration is preserved and automatically applied on future deployments of these services.
The configuration of the custom template is also preserved when the default configuration of cephadm changes. If the updated configuration is to be used, the custom template needs to be migrated manually.
The following templates for files that will be generated by cephadm can be
overridden. These are the names to be used when storing with
You can look up the file templates that are currently used by cephadm in
The following command applies a single line value:
ceph config-key set mgr/cephadm/<option_name> <value>
To set contents of files as template use the
ceph config-key set mgr/cephadm/<option_name> -i $PWD/<filename>
When using files as input to
config-key an absolute path to the file must
Then the configuration file for the service needs to be recreated. This is done using reconfig. For more details see the following example.
# set the contents of ./prometheus.yml.j2 as template ceph config-key set mgr/cephadm/services/prometheus/prometheus.yml \ -i $PWD/prometheus.yml.j2 # reconfig the prometheus service ceph orch reconfig prometheus
To disable monitoring and remove the software that supports it, run the following commands:
$ ceph orch rm grafana $ ceph orch rm prometheus --force # this will delete metrics data collected so far $ ceph orch rm node-exporter $ ceph orch rm alertmanager $ ceph mgr module disable prometheus
Deploying monitoring manually¶
If you have an existing prometheus monitoring infrastructure, or would like to manage it yourself, you need to configure it to integrate with your Ceph cluster.
Enable the prometheus module in the ceph-mgr daemon
ceph mgr module enable prometheus
By default, ceph-mgr presents prometheus metrics on port 9283 on each host running a ceph-mgr daemon. Configure prometheus to scrape these.
To enable the dashboard’s prometheus-based alerting, see Enabling Prometheus Alerting.
To enable dashboard integration with Grafana, see Enabling the Embedding of Grafana Dashboards.