provider/aws: EC2 instance - multiple private ips

[Djuke]

Feature: Adds support for multiple private IPs to the instance's first network interface.

Test: Passed all TestAccAWSInstance acceptance tests.

I wanted to add the ConflictsWith attribute to private_ip and private_ips but it conflicts with the computed argument which is still required for private_ip and should for private_ips.

[radeksimko]

Thanks for the PR,
this may conflict with #4231 - at least in git-sense, so I'll just reference it here for any future readers, especially for someone who may later pick that linked PR up, but based on the last comments in that thread it doesn't look like this PR should be waiting for it.

I'll get to the actual code review hopefully soon.

[Djuke]

this may conflict with #6761, but it is the same fix

[radeksimko]

I just merged your other PR #6761 as that one was easier to review - would you mind rebasing this one & resolving conflicts?

Thanks.

[Mil0dV]

Ping. (we'd very much like to see this make 0.7 :))

[radeksimko]

I think we'll need to refactor the whole conditional block to keep handling EC2 Classic vs VPC correctly.
I'm still ok with deprecating private_ip in favour of private_ips, but we will need to add some checks for EC2 Classic && len(private_ips) > 1 cases. I think we should error out as early as we can in such cases.

See #7568 which may help in making decisions. We need to be prepared for scenarios where we don't have the list of supported platforms though - I'd suggest we 1st try assigning multiple IPs and error out with an informative error message (e.g. ("Assigning %d IPs failed: %s (hint: EC2 Classic accounts don't support multiple private IPs for EC2 instances)", len(ips), err)).

I'm aware that it may be difficult to test on EC2 Classic and many/most of us run VPC-only accounts, but we can at least stick to expectations described in AWS docs: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-vpc.html#differences-ec2-classic-vpc

I recommend carefully reading specifically the following two sections:

• Multiple private IP addresses
• Accessing the Internet

[radeksimko]

Firstly sorry for the delay in providing feedback.

---

We don't currently have any good deprecation mechanisms for Computed fields unfortunately which may need addressing before we actually remove the old field, otherwise some users may get seriously confused.

The following

"${aws_instance.example.private_ip}"

would not print any warning nor error as Deprecated field neither if the field was missing in the schema. The second behaviour/bug has something to do with internal schema validation, I'm pretty sure it's logged somewhere under a different issue.

TL;DR What you did with Deprecated attribute is the best you can do today. 👍

---

I left you some comments above. The most important one is EC2 Classic compatibility.

[stack72]

associate not accociate

[frankh]

Is there any update on this?

[paddycarver]

Hi! This PR has been open for quite some time and waiting response from the community without any activity, so I'm going to close it out. We do this to try to keep our attention on PRs that are actively in-progress, it's not a comment on the code itself. If there is still interest in this PR, please feel free to reply, and we'll re-open this. Thanks!

[sergibarroso]

Is there any update on that, I would like to have this feature available in Terraform.

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.