If your business cannot tolerate downtime, you can prevent end user access to your clusters by disabling end user access.
Disabling end user access is recommended only when bringing down your clusters is not feasible.
This procedure is recommended for AWS or Azure clusters that you cannot bring down for some reason.
In the Data Warehouse service, click Overview, search
for and locate an activated environment you want to disable.
Click the environment options and select
Edit.
Click Configurations and make a note of the values for
setting Enable-IP_CIDR load balancer.
Obtain your IP address.
For example, run ifconfig on Windows or
ipconfig on Linux.
Set Enable IP-CIDR for the load balancer to your IP address.
For example, replace x.x.x.x/32 with your IP address 201.123.45.100/32.
Apply changes.
No user except you can access the Virtual Warehouses.
Wait until the cluster updates itself and goes back to Running state to continue the process.