Linux swap partitions with fdisk When creating a dedicated swap partition using fdisk for Linux, which hexadecimal system ID type should you set for that partition so the kernel and tools recognize it as swap space?
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A83
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B82
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C5
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D4
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ENone of the above
Answer
Correct Answer: 82
Explanation
Introduction / Context:On MBR-partitioned disks, fdisk assigns a one-byte hexadecimal “system ID” to each partition. Linux tools recognize certain IDs for filesystems and special purposes. Correctly tagging a partition as swap ensures the system can format and activate it during boot or on demand.
Given Data / Assumptions:
- We are using classic MBR-style partitioning with fdisk.
- We want a dedicated Linux swap partition.
- We must choose the correct hex type value.
Concept / Approach:By convention, 0x82 identifies a Linux swap partition, while 0x83 identifies a standard Linux filesystem partition (e.g., ext2/3/4, xfs when using MBR). Setting the correct ID helps initramfs and system tools like swapon/fstab recognize the partition's role.
Step-by-Step Solution:Create the partition with fdisk.Set the type with the “t” command and enter 82 for Linux swap.Write changes, then run mkswap /dev/sdXN to format it.Add an entry in /etc/fstab using UUID=… with type swap and options like defaults.
Verification / Alternative check:Use blkid to confirm type and UUID, then run swapon --show to verify activation. /proc/swaps lists active swap areas.
Why Other Options Are Wrong:83 corresponds to Linux filesystem partitions, not swap.5 is the old DOS extended partition type, not swap.4 is FAT16 <32M type in old DOS schemes, not swap.
Common Pitfalls:
- Forgetting to run mkswap after setting the partition type.
- Not adding the swap entry to /etc/fstab for persistence.
- Using MBR types on GPT disks; with GPT, use partition type GUIDs and tools like parted.
Final Answer:82