---
title: tar — Archive and Extract Files
date: 2026-10-18
time: 12:00
model: admin
category: programs
author_type: human
summary: A command that bundles multiple files into one archive or extracts them, and also handles gzip compression in one step.
tags: program, File and disk management, tar
---

**💬 "tar command"**

tar is a tool that bundles multiple files into a single file, and adding `-z` also applies gzip compression. It is the standard for Linux backup and distribution.

Options are often written together like `tar -czvf`, and when extracting you change it to `-x`.

- **Concept**: c is create (bundle), x is extract (unbundle), and t is list (list contents). These three letters are the core.
- **Left letter**: operation: `c` (create) / `x` (extract) / `t` (list contents)
- **Right letters**: options: `z` (gzip), `v` (verbose output), `f` (specify file name, usually at the end)
- **Path**: When extracting, specify the target directory with `-C` for safety.
- **Result**: The extension is conventionally .tar.gz or .tgz.
## Commonly used options

| Option | Description |
| --- | --- |
| -c | Creates a new archive |
| -x | Extracts an archive |
| -t | Lists contents without extracting |
| -z | Compresses or decompresses with gzip |
| -C <dir> | Works in the specified directory |

## Three essential command combinations

- `tar -czvf backup.tgz /var/www/html` — compresses and backs up the entire web root
- `tar -tzvf backup.tgz | head` — checks the contents and paths before extracting
- `tar -xzvf release.tgz -C /opt/app` — extracts safely to the specified directory
**💬 "Tell me a tip for using it without overlapping with nightly batch jobs"**

This is a step-by-step summary of situations commonly encountered on live production servers.

### Step 1 · Decide what to include and create the archive

Choose the backup target, then bundle it into a single file.

```
tar -czvf /backup/www-20261018.tgz /var/www/html
```

### Step 2 · Check the list before extracting

Check the contents first to prevent extracting to the wrong path.

```
tar -tzvf /backup/www-20261018.tgz | head -20
```

### Step 3 · Extract to the target directory

Don't overwrite the live directory directly; extract to a separate path and verify.

```
tar -xzvf /backup/www-20261018.tgz -C /tmp/restore
```

## How it's used in practice

### 1. Distributing release files

**Situation** — You need to extract release.tgz, which contains build artifacts, to /opt/app on the production server.

```
tar -xzvf /tmp/release.tgz -C /opt/app
```

**Result** — The list of extracted files is printed to stderr and they are placed under /opt/app.

**Point** — Specify the production directory with -C, and if possible move the previous version to .bak before extracting for safety.

### 2. Backing up only configuration files

**Situation** — You want to back up only the nginx/php configuration separately.

```
tar -czvf /backup/conf-20261018.tgz /etc/nginx /etc/php
```

**Result** — The configuration files are bundled into a single tgz for storage. Because absolute paths are included, their locations are preserved when restoring.

**Point** — Bundling with absolute paths simplifies restoration. For relative-path archives, make sure to check the base path when extracting.

## Things to watch out for

- When extracting, there is a risk of tar bombs (path traversal during extraction). For untrusted files, check the list with -t first.
- Files archived with absolute paths will overwrite their original location when extracted without -C, no matter where you extract them.
- Don't extract directly into a live directory; verify in a temporary path.
- Files being written, such as SQLite/DB files, can lose consistency, so use a separate method.
## Actual execution screen

This is the result after checking the list first (top) and then checking the actual backup file size (bottom).

![tar command execution result: archive list and backup file size](https://games.aidebatehub.com/assets/tar-demo.png)

Live production server

---
Source (HTML): https://games.aidebatehub.com/programs/linux/filesystem/tar.html
This file is an auto-generated Markdown twin of the DevHub document.