Cloud version: 13.0-CROC1

We will add Availability Zones (AZ) support for Subnets and Virtual Switches soon.

During update we will set AZ parameter for all Subnets and Virtual Switches.

AZs are made to increase availability of your application run in our Cloud. Issues in one AZ have no influence upon another AZs.

Now you can supply Availability Zone expticitly during Subnets’ and/or Virtual Switches’ creation (similar to Instances and Volumes).


If there are instances in different AZs in one Subnet or Virtual Switch, then this configuration is considered deprecated. Support for creation of instances in such networks will be restricted from March, 1st 2019. It won’t be possible to run Instances in AZ different from Subnet’s or Virtual Switch’s AZ.

In case such network is discovered in your project, you’ll be notified about it. Also, you will be informed about this network’s newly assigned AZ. If you need to change AZ for updated Subnet or Virtual Switch, please contact CROC Cloud support. For backward complatibility you will be able to run Instances in such networks till February, 28th 2019. However, we suggest you stop using such configurations during this period.

The connectivity between all instances created before update will remain.

Adding AZ parameter will affect Instances’, Subnets’ and Virtual Switches’ creation process. Details are below:

Subnet/Virtual Switch creation

Optional AZ parameter will be added.

Now during Subnets and Virtual Switches creation you may supply AZ, in which you want to create a resource. In case you don’t supply AZ, the Cloud will choose one automatically. It is impossible to predict an AZ, which will be elected by the Cloud – consistency of choice is not guaranteed.

Instances’ creation in Subnets/Virtual Switches

Main change of this update is a prohibition of creating “stretched” networks “stretched” across some AZs. You won’t be able to run Instances in different AZs in one network. When you create Instance, its AZ will be inherited from Subnet or Virtual Switch. Moreover, all Subnets and Virtual Switches must be in the same Availability Zone.

If you run Instance in AZ different from Subnet/Virtual Switch’s AZ, an appropriate error will be raised.

You can supply AZ during instance creation in “stretched” network. Network’s AZ will be used otherwise.