Verify Files With BLAKE2 (b2sum)
Compute or check fast, modern cryptographic hashes.
Run b2sum file.iso > file.b2, then b2sum -c file.b2 to verify it later.
01Command
Command
$ b2sum -c checksums.b202What it does
b2sum implements BLAKE2, which is faster than SHA-256 while remaining cryptographically strong, and -c checks a hash list just like sha256sum. It is the right tool to confirm a large download or backup copy arrived intact.
03Risk
!Warning: A checksum detects corruption, not tampering; verify the hash list came from a trusted source.
04Undo
✓No undo needed — this command does not change persistent state.
05Sources
- b2sum.1.en.html manual page (Debian bookworm)Evidence: Documents b2sum, which computes and checks BLAKE2 checksums.
Last verified: 2026-10-13 · Category: Security & Privacy
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