| --- |
| page_title: Upgrading to Terraform v1.5 |
| description: Upgrading to Terraform v1.5 |
| --- |
| |
| # Upgrading to Terraform v1.5 |
| |
| -> **Tip:** Use the version selector to view the upgrade guides for older Terraform versions. |
| |
| Terraform v1.5 is a minor release in the stable Terraform v1.0 series. |
| |
| Terraform v1.5 honors the |
| [Terraform v1.0 Compatibility Promises](https://developer.hashicorp.com/terraform/language/v1-compatibility-promises), |
| but there are some behavior changes outside of those promises that may affect a |
| small number of users. Specifically, the following updates may require |
| additional upgrade steps: |
| * [End of support for older macOS releases](#end-of-support-for-older-macos-releases) |
| * [Linux DNS resolver changes](#linux-dns-resolver-changes) |
| |
| See [the full changelog](https://github.com/hashicorp/terraform/blob/v1.5/CHANGELOG.md) |
| for more details. If you encounter any problems during upgrading which are not |
| covered this guide, please start a new topic in |
| [the Terraform community forum](https://discuss.hashicorp.com/c/terraform-core) |
| to discuss it. |
| |
| ## End of support for older macOS releases |
| |
| Terraform v1.5 will be the last release supported on macOS 10.13 High Sierra |
| and macOS 10.14 Mojave, both of which are no longer maintained by Apple. |
| |
| Terraform v1.5 itself supports these older macOS versions, but we strongly |
| recommend upgrading during the v1.5 release period so that you'll be ready to |
| use Terraform v1.6 once it is released. |
| |
| ## Linux DNS resolver changes |
| |
| Terraform on Linux uses a built-in DNS resolver rather than using the DNS |
| resolver from the platform's C library, because this allows Terraform to run |
| on systems with many different C libraries. |
| |
| In Terraform v1.5, the DNS resolver will now notice when you have set the |
| `trust-ad` option in your `/etc/resolve.conf` file, and will respond by setting |
| the "authentic data" option in outgoing DNS requests to better match the |
| behavior of the GNU libc DNS resolver. |
| |
| Terraform does not pay any attention to the corresponding option in responses, |
| but some DNSSEC-aware recursive resolvers return different responses when the |
| request option isn't set. This should therefore avoid some potential situations |
| where a DNS request from Terraform might get a different response than a |
| similar request from other software on your system. |
| |
| We don't expect this behavior change to be significant for most Terraform users. |
| |
| Note that this change affects only DNS requests made by Terraform CLI itself, |
| and not requests made by providers. Provider plugins are separate programs |
| which handle DNS resolution themselves and so may have different behavior. |
