Describe the issue:
Cephadm supports specifying miscellaneous config files for daemons with RHCS 6.0. We need to document this feature.


Describe the task you were trying to accomplish:
Set a custom configuration value on a daemon.

Suggestions for improvement:

See: https://docs.ceph.com/en/quincy/cephadm/services/index.html#custom-config-files

Updated text for Administration guide:

Cephadm supports specifying miscellaneous config files for daemons. To do so, users must provide both the content of the config file and the location within the daemon’s container at which it should be mounted. After applying a YAML spec with custom config files specified and having cephadm redeploy the daemons for which the config files are specified, these files will be mounted within the daemon’s container at the specified location.

Example service spec:

service_type: grafana
service_name: grafana
custom_configs:
  - mount_path: /etc/example.conf
    content: |
      setting1 = value1
      setting2 = value2
  - mount_path: /usr/share/grafana/example.cert
    content: |
      -----BEGIN PRIVATE KEY-----
      V2VyIGRhcyBsaWVzdCBpc3QgZG9vZi4gTG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFt
      ZXQsIGNvbnNldGV0dXIgc2FkaXBzY2luZyBlbGl0ciwgc2VkIGRpYW0gbm9udW15
      IGVpcm1vZCB0ZW1wb3IgaW52aWR1bnQgdXQgbGFib3JlIGV0IGRvbG9yZSBtYWdu
      YSBhbGlxdXlhbSBlcmF0LCBzZWQgZGlhbSB2b2x1cHR1YS4gQXQgdmVybyBlb3Mg
      ZXQgYWNjdXNhbSBldCBqdXN0byBkdW8=
      -----END PRIVATE KEY-----
      -----BEGIN CERTIFICATE-----
      V2VyIGRhcyBsaWVzdCBpc3QgZG9vZi4gTG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFt
      ZXQsIGNvbnNldGV0dXIgc2FkaXBzY2luZyBlbGl0ciwgc2VkIGRpYW0gbm9udW15
      IGVpcm1vZCB0ZW1wb3IgaW52aWR1bnQgdXQgbGFib3JlIGV0IGRvbG9yZSBtYWdu
      YSBhbGlxdXlhbSBlcmF0LCBzZWQgZGlhbSB2b2x1cHR1YS4gQXQgdmVybyBlb3Mg
      ZXQgYWNjdXNhbSBldCBqdXN0byBkdW8=
      -----END CERTIFICATE-----

To make these new config files actually get mounted within the containers for the daemons

ceph orch redeploy <service-name>
For example:

ceph orch redeploy grafana


Document URL:

https://access.redhat.com/documentation/en-us/red_hat_ceph_storage/5/html/administration_guide/cephadm-operations

Chapter/Section Number and Title:

Add a section 11.6 entitled: Cephadm Custom Config Files

Product Version:
RHCS 6.0

Environment Details:

Any other versions of this document that also needs this update:
N/A

Additional information: