问题
I need to get new external IP address every time when I recreate my instance. Current implementation may use previous ips. How can I achieve the goal with static or ephemeral ips? Or how can I get GCE ips pool?
回答1:
I am adding bellow information with Kolban.
For the external IP Google cloud has two categories:
Static external IP addresses
Ephemeral external IP addresses
The basic difference between these two are Static one is long term assignment until hey are explicitly released from that assignment, and remain attached to a resource until they are explicitly detached. Where, Ephemeral remain attached to a VM instance only until the VM is stopped and restarted or the instance is terminated. If an instance is stopped, any ephemeral external IP addresses that are assigned to the instance are released back into the general Compute Engine pool and become available for use by other projects.
As you are wishing for the new IP address for your instance, it seems Ephemeral external IP addresses is a better choice. But you can use the Static external IP addresses to create an IP pool anyway and rotate your reserved static external IP address, which has cost implications.
The external IP are configured in the accessConfigs. You can see accessConfigs if you describe your instance by below command in cloud shell.
$ gcloud compute instances describe [INSTANCE_NAME] --zone=[ZONE]
You can create a new VM and assign a static IP with the help of the Document and below command.
$ gcloud compute instances create [INSTANCE_NAME] --private-network-ip [IP_ADDRESS]
OR
You can change or assign an external IP in your existing VM following the steps of the document (GCLOUD), which are:
[Optional] Reserve a static external IP address (if you want to have the reserve external IP and this has cost implications).
Delete existing access configs.
Add the new external IP address.
回答2:
When you create a Compute Engine instance and give it a public IP address you have two choices for that IP. It can either be ephemeral ... this means that the IP address is assigned (randomly) by Google and may change the next time the Compute Engine is restarted. The alternative is that it is static. These are IP addresses that Google fixes for you and are explicitly yours until you release them. There is no charge for a static IP address if it is actively being used (eg has a Compute Engine running that is using it). However if unused, you are charged 24 cents a day (1 cent an hour).
If, for some reason, you need a new IP address for a compute engine on demand, you can reserve a new static IP address and associate that with your compute engine.
See also:
- Reserving a static external IP address
来源：https://stackoverflow.com/questions/59479659/google-compute-engine-how-to-bind-new-external-ip-address-to-the-instance