How to cleanly shut down (evacuate) a Stackato DEA

Posted by troyt on 2013-08-30 14:50
OS: Linux | Product: Stackato | tags: admin DEA stackato
Question: 

How do I shut down a DEA node (in a cluster) without causing any down time for the applications it hosts?

Answer: 

Stackato >=3.0

In Stackato 3.0 and greater, to shut down a DEA node cleanly, run the following command on the VM:

   $ kato node retire

Stackato 2.10

In versions of Stackato earlier than 3.0, to shut down a DEA node cleanly, run the following command on the VM:

   $ kill -s USR2 $(pgrep -f "ruby bin/dea")

Passing the USR2 signal to the 'dea' process will call the DEAs 'evacuate_apps_then_quit()' function, which ensures that app instances are migrated to a new DEA before the retiring DEA is shut down.