Bits of .NET

Accidentally did ‘git reset –hard’ and lost hours of work? Your commits aren’t deleted – they’re just orphaned. Here’s how to find them.

The Magic Command – Reflog:

git reflog

This shows every HEAD movement in your repository, even deleted commits. Output looks like:

a1b2c3d HEAD@{0}: reset: moving to HEAD~3
e4f5g6h HEAD@{1}: commit: Added user authentication  ← Your "lost" commit!
i7j8k9l HEAD@{2}: commit: Updated database schema

Recover the Commit:

# Find your commit hash from reflog
git reflog

# Reset to that commit
git reset --hard e4f5g6h

# Or create a new branch from it (safer)
git checkout -b recovery-branch e4f5g6h

Why This Works:
Git never truly deletes commits immediately. When you reset or delete a branch, Git removes the reference (pointer) but keeps the commit object. These orphaned commits exist for 30-90 days (configurable) before garbage collection removes them.

Advanced – Find Specific Lost Content:

# Search reflog for commits matching a pattern
git reflog --grep='authentication'

# Show all dangling commits (no branch points to them)
git fsck --lost-found

# View content of a dangling commit
git show COMMIT_HASH

Real Disaster Recovery Example:

# Scenario: Deleted feature branch by mistake
git branch -D feature-login
# ERROR: deleted branch 'feature-login'

# Solution 1: Find in reflog
git reflog | grep 'feature-login'
# Output: x1y2z3a HEAD@{5}: commit: Feature login complete

# Recreate branch
git checkout -b feature-login x1y2z3a

# Solution 2: Check recent commits
git fsck --no-reflogs
# Shows all unreachable commits

# Browse each one until you find your work
git log COMMIT_HASH --oneline

Prevent This Entirely – Git Aliases:

# Add safe reset aliases to ~/.gitconfig
[alias]
  # Soft reset (keeps changes in staging)
  undo = reset --soft HEAD~1
  
  # Show what would be deleted before hard reset
  check-reset = !git diff HEAD~1 HEAD
  
  # Safe hard reset with automatic backup
  safe-reset = !sh -c 'git branch backup-$(date +%Y%m%d-%H%M%S) && git reset --hard $1' -

# Usage
git safe-reset HEAD~3  # Creates backup branch automatically

Understanding Git’s 30-Day Safety Net:

# Check garbage collection settings
git config gc.reflogExpire
# Default: 90 days for reachable commits
# Default: 30 days for unreachable commits

# Extend safety net to 180 days
git config gc.reflogExpire 180.days.ago
git config gc.reflogExpireUnreachable 180.days.ago

Pro Tip – Periodic Backups:

# Create backup tags for important commits
git tag -a backup-before-refactor -m "Safety checkpoint"

# List all backup tags
git tag -l "backup-*"

# Restore from backup tag
git checkout backup-before-refactor
git checkout -b recovery-branch

Tags are permanent references. Even if you delete all branches, tagged commits never become unreachable.