Global shortcuts for emacs org-mode on Ubuntu

Let say F7 is bound, in emacs, to the org-clock-out function of Org Mode as a shortcut to quickly stop the current clock accumulating the time spent on a given task.

(global-set-key (kbd "<f7>") 'org-clock-out)

F7 can be sent to the emacs window via the command line with

xdotool search --name 'emacs@fold' key F7

If emacs needs to be displayed to the user (in case it was iconified or on another desktop), the windowactivate command can be added:

xdotool search --name 'emacs@fold' windowactivate key F7

On Ubuntu 14.04 this command can be bound to the F7 regardless of which window has focus, via the shortcuts tab of the keyboard section of System Settings as shown below:

Installing ceph with ceph-deploy

A ceph-deploy package is created for Ubuntu raring and installed with

dpkg -i ceph-deploy_0.0.1-1_all.deb

A ssh key is generated without a password and copied over to the root .ssh/authorized_keys file of each host on which ceph-deploy will act:

# ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/
The key fingerprint is:
The key's randomart image is:
+--[ RSA 2048]----+
|            .o.  |
|            oo.o |
|           . oo.+|
|          . o o o|
|        SE o   o |
|     . o. .      |
|      o +.       |
|       + =o .    |
|       .*..o     |
# for i in 12 14 15
 ssh bm00$ cat \>\> .ssh/authorized_keys < .ssh/

Each host is installed with Ubuntu raring and has a spare, unused, disk at /dev/sdb. The ceph packages are installed with:

ceph-deploy  install

The short version of each FQDN is added to /etc/hosts on each host, because ceph-deploy will assume that it exists:

for host in
 getent hosts | \
   sed -e 's/\.the\.re//' | ssh $host cat \>\> /etc/hosts

The ceph cluster configuration is created with:

# ceph-deploy new

and the corresponding mon are deployed with

ceph-deploy mon create

Even after the command returns, it takes a few seconds for the keys to be generated on each host: the ceph-mon process shows when it is complete. Before creating the osd, the keys are obtained from a mon with:

ceph-deploy gatherkeys

The osds are then created with:

ceph-deploy osd create

After a few seconds the cluster stabilizes, as shown with

# ceph -s
   health HEALTH_OK
   monmap e1: 3 mons at {bm0012=188.165:6789/0,bm0014=188.165:6789/0,bm0015=188.165:6789/0}, election epoch 24, quorum 0,1,2 bm0012,bm0014,bm0015
   osdmap e14: 3 osds: 3 up, 3 in
    pgmap v106: 192 pgs: 192 active+clean; 0 bytes data, 118 MB used, 5583 GB / 5583 GB avail
   mdsmap e1: 0/0/1 up

A 10GB RBD is created, mounted and destroyed with:

# rbd create --size 10240 test1
# rbd map test1 --pool rbd
# mkfs.ext4 /dev/rbd/rbd/test1
# mount /dev/rbd/rbd/test1 /mnt
# df -h /mnt
Filesystem      Size  Used Avail Use% Mounted on
/dev/rbd1       9.8G   23M  9.2G   1% /mnt
# umount /mnt
# rbd unmap /dev/rbd/rbd/test1
# rbd rm test1
Removing image: 100% complete...done.

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