As per my update in #5195:
Same here. I have run through the latest quick start documentation and am using Ubuntu 14.04.1 and Ceph firefly with ceph-deploy 1.5.17. Here are the applicable logs (I have only included those for ceph-node-2 as those for ceph-node-3 are duplicates):
ceph-deploy mon create ceph-node-2 ceph-node-3
[ceph_deploy.conf][DEBUG ] found configuration file at: /root/.cephdeploy.conf
[ceph_deploy.cli][INFO ] Invoked (1.5.17): /usr/bin/ceph-deploy mon create ceph-node-2 ceph-node-3
[ceph_deploy.mon][DEBUG ] Deploying mon, cluster ceph hosts ceph-node-2 ceph-node-3
[ceph_deploy.mon][DEBUG ] detecting platform for host ceph-node-2 ...
[ceph-node-2][DEBUG ] connection detected need for sudo
[ceph-node-2][DEBUG ] connected to host: ceph-node-2
[ceph-node-2][DEBUG ] detect platform information from remote host
[ceph-node-2][DEBUG ] detect machine type
[ceph_deploy.mon][INFO ] distro info: Ubuntu 14.04 trusty
[ceph-node-2][DEBUG ] determining if provided host has same hostname in remote
[ceph-node-2][DEBUG ] get remote short hostname
[ceph-node-2][DEBUG ] deploying mon to ceph-node-2
[ceph-node-2][DEBUG ] get remote short hostname
[ceph-node-2][DEBUG ] remote hostname: ceph-node-2
[ceph-node-2][DEBUG ] write cluster configuration to /etc/ceph/{cluster}.conf
[ceph-node-2][DEBUG ] create the mon path if it does not exist
[ceph-node-2][DEBUG ] checking for done path: /var/lib/ceph/mon/ceph-ceph-node-2/done
[ceph-node-2][DEBUG ] done path does not exist: /var/lib/ceph/mon/ceph-ceph-node-2/done
[ceph-node-2][INFO ] creating keyring file: /var/lib/ceph/tmp/ceph-ceph-node-2.mon.keyring
[ceph-node-2][DEBUG ] create the monitor keyring file
[ceph-node-2][INFO ] Running command: sudo ceph-mon --cluster ceph --mkfs -i ceph-node-2 --keyring /var/lib/ceph/tmp/ceph-ceph-node-2.mon.keyring
[ceph-node-2][DEBUG ] ceph-mon: set fsid to b6c3d00f-513e-40e5-9389-71481dc323e9
[ceph-node-2][DEBUG ] ceph-mon: created monfs at /var/lib/ceph/mon/ceph-ceph-node-2 for mon.ceph-node-2
[ceph-node-2][INFO ] unlinking keyring file /var/lib/ceph/tmp/ceph-ceph-node-2.mon.keyring
[ceph-node-2][DEBUG ] create a done file to avoid re-doing the mon deployment
[ceph-node-2][DEBUG ] create the init path if it does not exist
[ceph-node-2][DEBUG ] locating the `service` executable...
[ceph-node-2][INFO ] Running command: sudo initctl emit ceph-mon cluster=ceph id=ceph-node-2
[ceph-node-2][INFO ] Running command: sudo ceph --cluster=ceph --admin-daemon /var/run/ceph/ceph-mon.ceph-node-2.asok mon_status
[ceph-node-2][ERROR ] admin_socket: exception getting command descriptions: [Errno 2] No such file or directory
[ceph-node-2][WARNIN] monitor: mon.ceph-node-2, might not be running yet
[ceph-node-2][INFO ] Running command: sudo ceph --cluster=ceph --admin-daemon /var/run/ceph/ceph-mon.ceph-node-2.asok mon_status
[ceph-node-2][ERROR ] admin_socket: exception getting command descriptions: [Errno 2] No such file or directory
[ceph-node-2][WARNIN] ceph-node-2 is not defined in `mon initial members`
[ceph-node-2][WARNIN] monitor ceph-node-2 does not exist in monmap
[ceph-node-2][WARNIN] neither `public_addr` nor `public_network` keys are defined for monitors
[ceph-node-2][WARNIN] monitors may not be able to form quorum
The issue seems to come down to needing a declaration of public_network in your ceph.conf when adding new monitors to your cluster, even if your nodes only have a single network interface.
The only applicable entry in the (quick start) documentation that I can find is @ http://ceph.com/docs/master/start/quick-ceph-deploy/#create-a-cluster -> item number 3
It seems to imply that adding public_network is only needed if you have more than one network interface, and the wording should probably be changed to require the entry regardless of the number of network interfaces.
My solution was to add public_network to my ceph.conf on my admin ceph-deploy node and then issuing the following command: ceph-deploy --overwrite-conf mon create ceph-node-2 ceph-node-3
I hope this helps.