uncloud-mravi/doc/README-how-to-configure-remote-uncloud-clients.org

• What is a remote uncloud client?
  • Systems that configure themselves for the use with uncloud
  • Examples are VMHosts, VPN Servers, cdist control server, etc.
• Which access do these clients need?
  • They need read / write access to the database
• Possible methods
  • Overview
  • remote vs. local Django code execution
  • from_django

What is a remote uncloud client?

Systems that configure themselves for the use with uncloud

Examples are VMHosts, VPN Servers, cdist control server, etc.

Which access do these clients need?

They need read / write access to the database

Possible methods

Overview

	pros	cons
SSL based	Once setup, can access all django parts natively, locally	X.509 infrastructure
SSH -L tunnel	All nodes can use [::1]:5432	SSH setup can be fragile
ssh djangohost manage.py	All DB ops locally	Code is only executed on django host
https + token	Rest alike / consistent access	Code is only executed on django host
from_django	Everything is on the django host	main host can become bottleneck

remote vs. local Django code execution

• If manage.py is executed locally (= on the client), it can check/modify local configs
• However local execution requires a pyvenv + packages + db access
• Local execution also could make use of postgresql notify for triggering actions (which is quite neat)
• Remote execution (= on the primary django host) can acess the db via unix socket
• However remote execution cannot check local state

from_django

• might reuse existing methods like celery
• reduces the amount of things to be installed on the client to almost zero
• follows the opennebula model
• has a single point of failurebin