Few days ago, we cloned a VM test system with ASM. Changing the hostname in this case is mandatory from our network, we have lots of issues if they are duplicate.
But changing an Oracle Restart or generally, Grid Infrastructure setup’s hostname isn’t so easy – it’s written many configs. The only way is to deconfigure and configure the Grid Infrastructure stack. If you have no special services configured, it’s quite straightforward, as my colleague Benedikt Nahlovsky describes.
If there are additional / self-made services, just recreate them with your scripts (don’t forget to change the hostname in them if you used it!)
Hope you are doing well