verifying file integrity using md5sum

Ensuring file integrity is crucial, especially when transferring or downloading files. One way to verify this in Linux is by using the md5sum -c command, which checks whether a file’s MD5 checksum matches the expected value.

what is an md5 checksum?

An MD5 checksum is a 128-bit hash that serves as a fingerprint for a file. If the checksum of your downloaded file matches the provided one, the file is likely unaltered.

how to use md5sum -c?

• obtain the md5 checksum file: The checksum file typically looks like this:

d41d8cd98f00b204e9800998ecf8427e  filename.txt

• verify the file: Place the checksum file in the same directory as the files to verify, and run:

md5sum -c file_md5

If the file is intact, you’ll see:

filename.txt: OK

If a file fails the check, it will be marked as “FAILED”