On the isolated_nw which was user defined, the Docker network feature updated the /etc/hosts with the proper name resolution. Inside of container2 it is possible to ping container3 by name.

Cette solution semble etre un bon compromis quand on veut du lien bidirectionnel (ce qui n'est pas possible avec les links) :

http://sgillis.github.io/posts/2015-03-23-docker-dns.html
https://github.com/tonistiigi/dnsdock

/proc/pid/stat

nodejs process manager

Tout est dans man ps, je me le mets de côté pour écrire un plugin collectd :

ps -p $(cat /var/run/xx.pid) --no-headers --format rssize,vsize

(added to pocket)

En augmentant le rate limit de rsyslog ça passe

imuxsock lost

It took me some time to figure this one out, as everybody is using rsync and ssh-keys without passphrases, but I insist that an ssh-key should have a passphrase.

In my first attemts I got this error messages mailed to me by crontab:
Permission denied (gssapi-keyex,gssapi-with-mic,publickey,keyboard-interactive).

Here are the steps to automate a backup initiated from crontab using rsync, SSH and ssh-keys with a passphrase:

Make a set of SSH keys.
Setup SSH to use the agent automatically.
Login once as the user who's cron will run the backup script. You will be asked for a passphrase. When the machine reboots, you will need to login once more, to enter the passphrase again.
Make a backup script that includes some SSH variables.
This script could be as simple as this:
. /home/username/.ssh/variables
rsync -avz --delete /data/ example.com:data

N.B. This variables file only contains these lines:
SSH_AUTH_SOCK=/tmp/ssh-DmFcb18036/agent.18036; export SSH_AUTH_SOCK;
SSH_AGENT_PID=18037; export SSH_AGENT_PID;
echo Agent pid 18037;
Put that script in crontab.

That should do it for you, as it works like a charm for me!