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Add guide on copying GPT partition tables between disks and update ZFS pool creation tutorial for improved clarity and performance tips.
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‎blog/content/post/how-to-copy-gpt-partition-table.md‎

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---
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title: "How to Copy GPT Partition Table Between Disks"
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date: 2025-02-16T01:30:00-05:00
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draft: false
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tags: ["GPT", "Partitioning", "Linux", "RAID"]
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categories:
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- Storage
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- Linux
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- Disk Management
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author: "Matthew Mattox - mmattox@support.tools"
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description: "A quick guide on copying a GPT partition table between disks when setting up RAID or disk cloning."
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more_link: "yes"
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url: "/how-to-copy-gpt-partition-table/"
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---
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## Why Copy GPT Partition Tables?
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When configuring **RAID** or setting up identical disks, it's essential to have the **same partition tables** across all disks. While `sfdisk` worked well for **MBR (msdos) partition tables**, it does **not** support **GPT**. Fortunately, we can achieve this using `sgdisk`.
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## Prerequisites and Safety Checks
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### Backup Your Data
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🔴 **WARNING**: Always backup important data before manipulating partition tables!
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```bash
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# Create a backup of the partition table
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sudo sgdisk --backup=disk1_backup.gpt /dev/sd_src
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# Optional: Create full disk image
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sudo dd if=/dev/sd_src of=disk1_full_backup.img bs=4M status=progress
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```
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### Verify Disk Identification
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```bash
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# List all disks with their identifiers
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lsblk -o NAME,SIZE,MODEL,SERIAL
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# Show detailed disk information
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sudo fdisk -l
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```
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## Install `gdisk`
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Install `gdisk` based on your distribution:
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### Ubuntu/Debian:
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```bash
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sudo apt-get install -y gdisk
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```
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### RHEL/CentOS/Fedora:
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```bash
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sudo dnf install -y gdisk
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```
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### Arch Linux:
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```bash
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sudo pacman -S gptfdisk
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```
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## Copy GPT Partition Table
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### Basic Copy Operation
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```bash
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# Copy partition table
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sudo sgdisk -R /dev/sd_dest /dev/sd_src
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# Verify the operation succeeded
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echo $?
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```
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### Advanced Copy Options
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```bash
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# Copy with progress information
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sudo sgdisk --display-alignment -R /dev/sd_dest /dev/sd_src
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# Copy and preserve original UUIDs (use with caution)
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sudo sgdisk --backup=original.gpt /dev/sd_src
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sudo sgdisk --load-backup=original.gpt /dev/sd_dest
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```
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### Explanation:
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- `-R /dev/sd_dest /dev/sd_src` → Copies the partition table from **source disk** to **destination disk**
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- `--display-alignment` → Shows alignment information during copy
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- `--backup` → Creates a backup of the partition table
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- `--load-backup` → Restores a partition table from backup
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## Update UUIDs for Unique Identification
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### Randomize UUIDs
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```bash
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# Generate new UUIDs
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sudo sgdisk -G /dev/sd_dest
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# Verify unique UUIDs
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sudo blkid /dev/sd_src*
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sudo blkid /dev/sd_dest*
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```
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### Why is this necessary?
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- Prevents **duplicate partition** detection
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- Avoids **boot failures** and system confusion
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- Essential for **RAID** and **multi-disk** setups
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- Prevents **mount conflicts** in fstab
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## Verification Steps
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### Check Partition Table
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```bash
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# Compare partition tables
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sudo sgdisk -p /dev/sd_src
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sudo sgdisk -p /dev/sd_dest
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# Verify alignment
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sudo sgdisk --verify /dev/sd_dest
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```
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### Validate Partitions
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```bash
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# List all partitions
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sudo fdisk -l /dev/sd_dest
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# Check partition details
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sudo parted /dev/sd_dest print
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```
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## Troubleshooting
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### Common Issues and Solutions
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1. **Disk Busy Error**
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```bash
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# Unmount all partitions
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sudo umount /dev/sd_dest*
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# Stop any RAID arrays
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sudo mdadm --stop /dev/md*
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```
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2. **Invalid GPT Error**
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```bash
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# Fix GPT errors
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sudo sgdisk --verify /dev/sd_dest
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sudo sgdisk --rebuild-gpt /dev/sd_dest
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```
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3. **UUID Conflicts**
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```bash
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# Force UUID regeneration
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sudo sgdisk --randomize-guids /dev/sd_dest
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```
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## Real-World Examples
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### Setting up Software RAID
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```bash
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# Copy partition table to all RAID disks
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for disk in /dev/sd[b-e]; do
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sudo sgdisk -R $disk /dev/sda
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sudo sgdisk -G $disk
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done
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```
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### Preparing for Disk Migration
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```bash
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# Copy and preserve alignment
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sudo sgdisk --display-alignment -R /dev/newdisk /dev/olddisk
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sudo sgdisk -G /dev/newdisk
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```
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## Recovery Procedures
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### Restore from Backup
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```bash
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# Restore partition table from backup
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sudo sgdisk --load-backup=disk1_backup.gpt /dev/sd_dest
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# Verify restoration
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sudo sgdisk -p /dev/sd_dest
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```
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### Emergency Recovery
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```bash
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# Attempt to recover damaged GPT
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sudo sgdisk --rebuild-gpt /dev/sd_dest
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# Create new protective MBR
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sudo sgdisk --gpttombr /dev/sd_dest
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```
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## Conclusion
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Using `sgdisk`, you can reliably clone **GPT partition tables** between disks, ensuring consistency in **RAID setups** and **disk cloning operations**. This method provides robust support for **modern GPT-based partitions** with built-in safety features and verification options.
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### Best Practices
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1. **Always backup** before partition operations
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2. **Verify disk identifiers** carefully
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3. **Check UUIDs** after copying
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4. **Test mount points** after completion
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5. **Keep backup files** until verification is complete

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