Ceph

The init-ceph script (usually installed as /etc/init.d/ceph) assumes that there is only one daemon running on the node.

Output example:

cmccabe@metropolis:~/src/ceph/src$ ./ps-ceph.pl 
 3367    ./cmon -i a -c ceph.conf 
 3371    ./cmon -i b -c ceph.conf 
 3375    ./cmon -i c -c ceph.conf 
 3502    ./cosd -i 0 -c ceph.conf 
 3545    ./cmds -i a -c ceph.conf 
 3569    ./cmds -i b -c ceph.conf 
 3592    ./cmds -i c -c ceph.conf 
 14624   vim rados.py 
 cmccabe@metropolis:~/src/ceph/src$ ./init-ceph status
=== mon.a === 
 3367 running...

We have been recommending that people run multiple cosds (one per disk), so having multiple daemons on a single node is clearly a supported configuration.