Ceph

I deployed Ceph via ceph-deploy to a new host:

$ ceph-deploy install ceph02

This installed the following packages:

ca-certificates apt-transport-https ceph ceph-mds radosgw

After that, I tried to add the first OSD on that host:

$ ceph-deploy osd prepare ceph02:/dev/sda

This partitioned and formated the disk.
However, the OSD didn't come up:

...
[ceph02][WARNIN] INFO:ceph-disk:Running command: /sbin/sgdisk --typecode=1:4fbd7e29-9d25-41b8-afd0-062c0ceff05d -- /dev/sda
[ceph02][DEBUG ] The operation has completed successfully.
[ceph02][WARNIN] DEBUG:ceph-disk:Calling partprobe on prepared device /dev/sda
[ceph02][WARNIN] INFO:ceph-disk:Running command: /sbin/udevadm settle
[ceph02][WARNIN] INFO:ceph-disk:Running command: /sbin/partprobe /dev/sda
[ceph02][WARNIN] INFO:ceph-disk:Running command: /sbin/udevadm settle
[ceph02][WARNIN] INFO:ceph-disk:Running command: /sbin/udevadm trigger --action=add --sysname-match sda1
[ceph02][INFO  ] checking OSD status...
[ceph02][INFO  ] Running command: sudo ceph --cluster=ceph osd stat --format=json
[ceph02][WARNIN] there is 1 OSD down
[ceph02][WARNIN] there is 1 OSD out

When I investigated on the host ceph02, I noticed the Python module 'pkg_resources':

$ service ceph start
Traceback (most recent call last):
  File "/usr/bin/ceph-detect-init", line 5, in <module>
    from pkg_resources import load_entry_point
ImportError: No module named pkg_resources
ERROR:ceph-disk:Failed to activate
ceph-disk: Command '/usr/bin/ceph-detect-init' returned non-zero exit status 1
ceph-disk: Error: One or more partitions failed to activate

The package 'ceph-deploy' depends on 'python-pkg-resources' and 'python-setuptools'.
I installed both. After that '/usr/bin/ceph-detect-init' worked.

I had to remove the partitions on /dev/sda and tried to add the OSD again:

$ ceph-deploy osd prepare ceph02:/dev/sda
...
[ceph02][DEBUG ] The operation has completed successfully.
[ceph02][WARNIN] DEBUG:ceph-disk:Calling partprobe on prepared device /dev/sda
[ceph02][WARNIN] INFO:ceph-disk:Running command: /sbin/udevadm settle
[ceph02][WARNIN] INFO:ceph-disk:Running command: /sbin/partprobe /dev/sda
[ceph02][WARNIN] INFO:ceph-disk:Running command: /sbin/udevadm settle
[ceph02][WARNIN] INFO:ceph-disk:Running command: /sbin/udevadm trigger --action=add --sysname-match sda1
[ceph02][INFO  ] checking OSD status...
[ceph02][INFO  ] Running command: sudo ceph --cluster=ceph osd stat --format=json
[ceph_deploy.osd][DEBUG ] Host ceph02 is now ready for osd use.

OS on all machines: Ubuntu 14.04 x64 LTS
Ceph release: 9.2.0-1trusty (infernalis)