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Terraform Debug

Step-01: Introduction

  • Learn about Terraform Debug
  • TF_LOG & TF_LOG_PATH
  • TF_LOG - Allowed Values or Desired Log Levels
  • TRACE: Very detailed verbosity, shows every step taken by Terraform and produces enormous outputs with internal logs.
  • DEBUG: describes what happens internally in a more concise way compared to TRACE.
  • ERROR: shows errors that prevent Terraform from continuing.
  • WARN: logs warnings, which may indicate misconfiguration or mistakes, but are not critical to execution
  • INFO: shows general, high-level messages about the execution process.
  • Important Note:

Step-02: Setup Trace logging in Terraform

# Terrafrom Trace Log Settings
export TF_LOG=TRACE
export TF_LOG_PATH="terraform-trace.log"
echo $TF_LOG
echo $TF_LOG_PATH

# Terraform Initialize
terraform init

# Terraform Validate
terraform validate

# Terraform Plan
terraform plan

# Terraform Apply
terraform apply -auto-approve

# Terraform Destroy
terraform destroy -auto-approve

# Clean-Up
rm -rf .terraform*
rm -rf terraform.tfstate*
rm terraform-trace.log

Step-03: Setup these Environment Variables permanently in your desktops

Linux Bash

  • Open your .bashrc which is located in your $home directory 
# Linux Bash
cd $HOME
vi .bashrc

# Terraform log settings
export TF_LOG=TRACE
export TF_LOG_PATH="terraform-trace.log"

# Verify after saving the file in new terminal 
$ echo $TF_LOG
TRACE
$ echo $TF_LOG_PATH
terraform-trace.log

Windows Powershell

  • Setup using Powershell profile
  • Open $profile command in a PowerShell
  • Once that file is opened add the following lines.
  • Now close and reopen the console and type the following to verify that it worked.
# Windows Powershell - Terraform log settings
$env:TF_LOG="TRACE"
$env:TF_LOG_PATH="terraform.txt"

# Open new powershell window & Verify
echo $env:TF_LOG
echo $env:TF_LOG_PATH

MAC OS

  • Update the values in .bash_profile at the end of file
# MAC OS
cd $HOME
vi .bash_profile

# Terraform log settings
export TF_LOG=TRACE
export TF_LOG_PATH="terraform-trace.log"

# Verify after saving the file in new terminal 
$ echo $TF_LOG
TRACE
$ echo $TF_LOG_PATH
terraform-trace.log

Step-04: Terraform Crash Log

  • If Terraform ever crashes (a "panic" in the Go runtime), it saves a log file with the debug logs from the session as well as the panic message and backtrace to crash.log.
  • Generally speaking, this log file is meant to be passed along to the developers via a GitHub Issue.
  • As a user, you're not required to dig into this file.
  • How to read a crash log?