Error: Failed to install provider

Fix terraform "Error: Failed to install provider"

TL;DR: terraform init could not download or verify a provider plugin. Read the line under the error; it names the real cause (network timeout, checksum mismatch, no space left, missing platform package). Fix that cause, then re-run terraform init. Most cases are transient network failures or a stale .terraform.lock.hcl.

The error

Error: Failed to install provider

Error while installing hashicorp/aws v6.47.0: write
.terraform/providers/registry.terraform.io/hashicorp/aws/6.47.0/linux_amd64/terraform-provider-aws_v6.47.0_x5: no space left on
device

(Your sub-line will differ. Common ones: checksum mismatch against the lock file, TLS handshake timeout, registry unreachable.)

Steps

1. Read the sub-error. It is the actual diagnosis. Categorize it:

• no space left on device: free disk space.
• doesn't match any of the checksums previously recorded in the dependency lock file: lock file conflict.
• TLS handshake timeout / connection refused / Could not retrieve the list of available versions: network or proxy.
• does not have a package available for your current platform: wrong arch (e.g. 32-bit).

1. For lock-file checksum conflicts, regenerate the lock file:

   rm .terraform.lock.hcl
   terraform init

Expected: providers install, and a fresh lock file is written. Commit it.

1. For network failures, check reachability and retry. Behind a corporate proxy, export the proxy vars first:

   curl -s https://registry.terraform.io/.well-known/terraform.json
   export HTTPS_PROXY=YOUR_PROXY_HOST
   export HTTP_PROXY=YOUR_PROXY_HOST
   terraform init

Expected: the registry answers and the install proceeds.

1. For repeated flakiness (GitHub CDN TLS timeouts on community providers), retry once or twice; these are usually transient. Expected: a later init succeeds with no config change.

When this applies

• terraform init fails at the "Installing ..." step with any sub-error.
• You changed provider versions, platforms, or the lock file.

When it does NOT apply

• Init fails earlier at "Finding ... versions" with Failed to query available provider packages. That is version-constraint or registry-access, a different fix.
• The provider installs but plan fails with auth errors. That is provider configuration, not installation.

Tool and version compatibility

• Terraform CLI 0.13+ (provider source model) through 1.x.
• registry.terraform.io and community providers hosted on GitHub releases.

Why it happens

Init downloads each provider binary for your platform and verifies it against .terraform.lock.hcl checksums. Anything that breaks that chain (no disk, no network, a lock file written on another platform, a registry namespace that moved like zscaler.com/zpa to zscaler/zpa) fails the whole install.

Edge cases and pitfalls

• Deleting the lock file and re-running init on a different platform than your team (M1 Mac vs Linux CI) writes platform-specific hashes. Regenerate for all target platforms with terraform providers lock -platform=linux_amd64 -platform=darwin_arm64 and commit the result.
• Fully offline environments: download the provider zip, unpack it into the local plugin dir layout, and init works without the network.
• Do not hand-edit checksums in the lock file. Regenerate it.