如何让parted自动将下一个分区紧接在前一个分区之后创建？

Hey there! I've helped plenty of folks transition from clunky fdisk pipe scripts to cleaner parted workflows, so let's break down how to get those consecutive, dynamically-sized partitions set up automatically.

First, understand parted's non-interactive superpower #

Unlike fdisk which relies on feeding keystrokes via pipes (prone to breakage if disk sizes shift), parted has a --script flag that lets you run commands directly in batch mode—perfect for your dynamic size needs. No more guessing which keystroke to pipe next!

Step 1: Initialize the partition table #

First, wipe any existing partition table and create a new one (use msdos instead of gpt if you need MBR for legacy systems):

parted --script /dev/sda mklabel gpt

Double-check /dev/sda is your target disk—wrong disks mean permanent data loss!

Step 2: Calculate dynamic sizes & create consecutive partitions #

Assuming you already have logic to compute A, Y, X (stick to a consistent unit like MiB/GiB), you can define exact start/end points for each partition. The core trick is setting each partition's start to the previous one's end.

Here's a full script example with dynamic size calculations:

#!/bin/bash

TARGET_DISK="/dev/sda"

# Example: Dynamically calculate sizes based on total disk space
# Adjust this logic to match your actual requirements
TOTAL_SIZE_MIB=$(blockdev --getsize64 $TARGET_DISK | awk '{print int($1 / 1048576)}')
A=$((TOTAL_SIZE_MIB * 20 / 100))  # 20% of total disk space
Y=$((TOTAL_SIZE_MIB * 30 / 100))  # 30% of total disk space
X=$((TOTAL_SIZE_MIB - A - Y - 1))  # Remaining space minus 1MiB for alignment

# Initialize partition table
parted --script $TARGET_DISK mklabel gpt

# Create first partition: starts at 1MiB (avoids SSD alignment issues), ends at 1+A MiB
parted --script $TARGET_DISK mkpart primary 1MiB $((1 + A))MiB

# Create second partition: starts right after the first, size Y MiB
parted --script $TARGET_DISK mkpart primary $((1 + A))MiB $((1 + A + Y))MiB

# Create third partition: starts right after the second
# Use this line to enforce exact X size:
# parted --script $TARGET_DISK mkpart primary $((1 + A + Y))MiB $((1 + A + Y + X))MiB
# Or use this to fill the remaining disk space:
parted --script $TARGET_DISK mkpart primary $((1 + A + Y))MiB 100%

# Verify the final partition layout
parted --script $TARGET_DISK print

Alternative: Auto-detect the last partition's end #

If you don't want to track start/end values manually (great for flexible workflows), you can query parted for the end of the last created partition:

# After creating the first partition, get its end position in MiB
LAST_PART_END=$(parted --script $TARGET_DISK unit MiB print | grep -E '^ 1' | awk '{print $3}' | sed 's/MiB//')

# Create second partition starting exactly where the first ended
parted --script $TARGET_DISK mkpart primary ${LAST_PART_END}MiB $((LAST_PART_END + Y))MiB

This is ideal if you plan to add/remove partitions dynamically later on.

Key tips to avoid headaches #

• Stick to consistent units (MiB/GiB are safer than raw sectors) to prevent calculation errors.
• Start partitions at 1MiB instead of 0% to avoid alignment issues with modern SSDs and large disks.
• Always test the script on a disposable disk (like a USB drive) before running it on production hardware!

内容的提问来源于stack exchange，提问作者Paul D Smith