The Linux tar Command: Wrapping My Head Around Archives

I needed to send a 500MB codebase to a client. "Just use tar," my boss said. Six hours later, after three failed uploads and a corrupted archive, I finally understood tar—through making every mistake possible.

Let me save you those six hours.

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My tar Disaster

First, I tried creating a simple archive:

tar -cf site.tar /var/www/html

Seemed to work. But when the client tried to extract, they got warnings. Turns out I needed to compress!

Compression flags:

• -z = gzip (.tar.gz or .tgz)
• -j = bzip2 (.tar.bz2)
• -J = xz (.tar.xz)

Correct command:

tar -czf site.tar.gz /var/www/html

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Understanding tar Options

Create Archives

tar -czf archive.tar.gz directory/
tar -cjf archive.tar.bz2 directory/
tar -cJf archive.tar.xz directory/

The -c = create. Always put it first!

Extract Archives

tar -xzf archive.tar.gz
tar -xjf archive.tar.bz2
tar -xJf archive.tar.xz

The -x = extract.

List Contents

tar -tzf archive.tar.gz

See what's inside without extracting.

Common Flags (can be combined)

• -v = verbose (show files)
• -p = preserve permissions
• -m = preserve modification time
• --strip-components=N = remove N directory levels

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The tar Mistakes That Cost Me Time

1. Trying to extract a file instead of an archive

You can't extract with create flag!

tar: Refusing to read archive body is disabled because -i option is not set

Fix: Use -x (extract), not -c (create).

2. Forgetting compression

Uncompressed tar files are huge:

tar -cf site.tar site/
# Results in: site.tar (2GB)
 
tar -czf site.tar.gz site/
# Results in: site.tar.gz (200MB)

3. Absolute paths

Extracting an absolute path puts files in /, not your current directory:

tar -xzf archive.tar.gz     # Extracts to /var/www if that's in archive
tar -xzf archive.tar.gz -C /tmp  # Extracts to /tmp instead

4. Not preserving permissions

Need -p to keep file modes:

tar -xpf archive.tar.gz

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tar Commands That Actually Work

Creating a compressed archive

tar -czvf site-backup.tar.gz /var/www/html

Create, verbose, gzip, preserve perms.

Extracting to a specific directory

tar -xzf backup.tar.gz -C /tmp

Extract to /tmp.

Listing with details

tar -tvf archive.tar.gz

Verbose list.

Adding files to existing archive

tar -rf archive.tar newfile.txt

But only works for uncompressed!

Updating files in archive

tar -uf archive.tar updated-file.txt

Like adding but smarter.

Excluding files

tar -czf site.tar.gz --exclude='.git' --exclude='node_modules' site/

Skip unnecessary directories.

Including only certain files

tar -czf docs.tar.gz --include='*.md' --include='*.txt' project/

Only documentation files.

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The tar Command Builder: Visual Archiving

Building tar commands is tricky—there are many flags and order matters. The tar Command Builder helps:

• Click to create or extract mode
• Select compression type visually
• Add excludes with checkboxes
• See the command build in real-time

Point, click, extract.

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Quick Reference

Task	Command
Create tar	tar -cf out.tar dir/
Create gzip	tar -czf out.tar.gz dir/
Create bzip2	tar -cjf out.tar.bz2 dir/
Extract	tar -xf archive.tar.gz
List contents	tar -tf archive.tar.gz
Extract to dir	tar -xf -C /tmp
Verbose create	tar -czvf out.tar.gz dir/
Exclude	tar --exclude='.git' -czf out.tar.gz dir/

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Advanced tar Techniques

Incremental backup

tar -czvf backup.tar.gz --listed-incremental=backup.snar /var/www

First run creates full. Subsequent runs are incrementals!

Remote transfer

tar -czf - /var/www | ssh user@server "tar -xzf - -C /backup"

Archive locally, transfer through SSH, extract remotely.

Split archive

tar -czf - bigdir/ | split -b 100M - backup.tar.gz.

Split into 100MB chunks for CD/DVD.

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Lessons from tar Disasters

1. Use -z (gzip) by default — compression saves bandwidth and time.

2. Use -v (verbose) when learning — see each file being processed.

3. Use -p (preserve) always — protects permissions and timestamps.

4. Use -C to specify extraction directory — avoids accidental wrong location.

5. Check contents first with -t — see what's inside before extracting.

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Conclusion: tar Is Your Friend

tar became my nightmare, then my ally. The key is understanding the create/extract distinction and using compression.

The tar Command Builder makes building commands easy—select what you need, copy the result.

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Further Reading

• GNU tar Manual
• tar Command Builder
• Linux Tools Library