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turn off controllers node

asked 2019-03-03 07:06:42 -0500

Meraj gravatar image

Hi, we use 2 controller nodes,20 compute nodes and 2 storage nodes in our network. what will happen if we turn off or lock both controller nodes ? is this affecting our running instances ?


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answered 2019-03-03 07:34:29 -0500

It will affect networking.

Central routers are deployed on the controllers. When both controllers are down, instances can't access devices outside of their network, and won't be accessible from outside.

Distributed routers are mostly deployed on the compute nodes. Instances with floating IPs won't be affected, but traffic from instances without floating IPs still goes through the controllers. Such instances won't be able to dial out.

Another aspect is DHCP. Instances need to renew DHCP leases at some time. If your DHCP servers run on the controllers, instances will lose their static IP addresses.

There may be other impacts depending on your specific setup. Carefully analyse which components run on the controllers and consider whether their absence might impact instance operation.

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Thanks for your response. In our network, all instances are using floating ip and DHCP is not used.

Meraj gravatar imageMeraj ( 2019-03-03 08:12:32 -0500 )edit

DHCP is not used? This is rare. How do instances get their IP addresses then?

Also, if instances are connected to tenant networks that are attached to centralized routers, they will lose connectivity when you shut down the controllers.

Bernd Bausch gravatar imageBernd Bausch ( 2019-03-03 21:20:59 -0500 )edit

Of course, your instances may be connected to provider networks, but if that's the case, you should not have floating IPs.

Bernd Bausch gravatar imageBernd Bausch ( 2019-03-03 21:22:03 -0500 )edit

answered 2019-03-04 12:16:26 -0500

yasin lachiny gravatar image

updated 2019-03-04 12:17:24 -0500

no they are ok but you can not make another vm no one use selfservice and if you use provider nothing happen to your network i test it

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Asked: 2019-03-03 07:06:42 -0500

Seen: 178 times

Last updated: Mar 04 '19