ceph-ansible/README.md

ceph-ansible
============

Ansible playbook for Ceph!

## What does it do?

General support for:

* Monitors
* OSDs
* MDSs
* RGW

More details:

* Authentication (cephx), this can be disabled.
* Supports cluster public and private network.
* Monitors deployment. You can easily start with one monitor and then progressively add new nodes. So can deploy one monitor for testing purpose. For production, I recommend to always use an odd number of monitors, 3 tends to be the standard.
* Object Storage Daemons. Like the monitors you can start with a certain amount of nodes and then grow this number. The playbook either supports a dedicated device for storing the journal or both journal and OSD data on the same device (using a tiny partition at the beginning of the device).
* Metadata daemons.
* Collocation. The playbook supports collocating Monitors, OSDs and MDSs on the same machine.
* The playbook was validated on Debian Wheezy, Ubuntu 12.04 LTS and CentOS 6.4.
* Tested on Ceph Dumpling and Emperor.
* A rolling upgrade playbook was written, an upgrade from Dumpling to Emperor was performed and worked.


## Setup with Vagrant

Run your virtual machines:

```bash
$ vagrant up
...
...
...
 ____________
< PLAY RECAP >
 ------------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||


mon0                       : ok=16   changed=11   unreachable=0    failed=0
mon1                       : ok=16   changed=10   unreachable=0    failed=0
mon2                       : ok=16   changed=11   unreachable=0    failed=0
osd0                       : ok=19   changed=7    unreachable=0    failed=0
osd1                       : ok=19   changed=7    unreachable=0    failed=0
osd2                       : ok=19   changed=7    unreachable=0    failed=0
rgw                        : ok=20   changed=17   unreachable=0    failed=0
```

Check the status:

```bash
$ vagrant ssh mon0 -c "sudo ceph -s"
    cluster 4a158d27-f750-41d5-9e7f-26ce4c9d2d45
     health HEALTH_OK
     monmap e3: 3 mons at {ceph-mon0=192.168.0.10:6789/0,ceph-mon1=192.168.0.11:6789/0,ceph-mon2=192.168.0.12:6789/0}, election epoch 6, quorum 0,1,2 ceph-mon0,ceph-mon1,ceph-mon
     mdsmap e6: 1/1/1 up {0=ceph-osd0=up:active}, 2 up:standby
     osdmap e10: 6 osds: 6 up, 6 in
      pgmap v17: 192 pgs, 3 pools, 9470 bytes data, 21 objects
            205 MB used, 29728 MB / 29933 MB avail
                 192 active+clean
```

To re-run the Ansible provisioning scripts:

```bash
$ vagrant provision
```

## Specifying fsid and secret key in production

The Vagrantfile specifies an fsid for the cluster and a secret key for the
monitor. If using these playbooks in production, you must generate your own `fsid`
in `group_vars/all` and `monitor_secret` in `group_vars/mons`. Those files contain
information about how to generate appropriate values for these variables.