A checksum is a value created from a binary file that can be used to validate its authenticity and integrity. An example of a checksum is MD4, MD5 and SHA-1.

learn more… | top users | synonyms

1
vote
3answers
4k views

How can I copy files to an external drive and verify their integrity in OS X?

I'm moving large amounts of data from one external drive to another larger one. The files are important and the smaller drives need to be cleared and reused (HD camera). Is there some utility for ...
0
votes
1answer
140 views

What type of malware can reside in windows restore?

I was reading aking1012's comment on How to create Windows Vista/Windows 7 Startup disk or Rescue disk or system restore points on a CD? . He says that: The first thing I usually do is disable ...
0
votes
2answers
790 views

Which backup apps verify the checksum of what they've written?

I've been using TeraCopy and DirSyncPro for moving & syncing large file sets (1.5TB) between 3 locations- a SMB NAS share, a local drive & an external. Neither of these solutions are quite ...
2
votes
1answer
214 views

Hardware digital signature

Is it possible to show how generate a digital signature, a checksum, or something along those lines based on your computer hardware using an Ubuntu Live CD? So, once the first digital signature is ...
2
votes
3answers
2k views

Looking for OS X utility to verify/validate copied files/directories - checksum / SFV / MD5

Looking for the best way to easily validate the integrity of files/folder in OS X when copied from one location to another. I've downloaded SuperSFV but it appears to be very slow. Also new to the ...
1
vote
3answers
300 views

tool for maintain incrementally the checksum of a large set of files

I need a tool to generate and maintain the checksum (MD5, SHA1, it does not matter) of all files in a folder or a set of folders, recursively. Sometimes I will add/update/remove some files and I ...
1
vote
1answer
139 views

On Mac, after downloading a file, how to you do a checksum?

I want to do a checksum on a file I downloaded on my Mac. How can I do this?
0
votes
4answers
68 views

rsyncing - ignoring checksums

Trying to copy a bunch of data over and time, unfortunately, is of the essence. I'd like to do an rsync of all the data in one direction, pretty much rsync just clobbers what's over on the ...
8
votes
3answers
4k views

What are these Google SHA1 images? [closed]

If you look at this page you'll see an monochrome image. Above it says Tip: Use the SHA1 checksum shown to verify file integrity. However, I don't know if that's related. What are these ...
3
votes
2answers
2k views

What is the best way to make Calculate SHA1 as a context menu option in Mac OS X?

In order to calculate the SHA1 checksum of a downloaded file, I could type /usr/bin/openssl sha1 in Terminal and then drag there the file which I want check. To make it simpler, one could enable a ...
4
votes
2answers
561 views

Mass Checksumming tool for Windows?

I'm looking for a command line tool for windows that will go over a directory tree (recursively) and output a list of all the files in there, and a checksum for each file (can be CRC, MD5, whatever). ...
2
votes
1answer
799 views

Is it possible to check a FLV for data corruption?

I have some FLV videos and I'd like to check them for possibile data corruption, even if I'm able to play them without problems. I don't really know if FLV videos store an embedded checksum string for ...
3
votes
1answer
2k views

Is it possible to check a PDF for data corruption?

I have some PDF documents and I'd like to check them for possibile data corruption, even if I'm able to display them without problems. I don't really know if PDF documents store an embedded checksum ...
3
votes
3answers
3k views

A gigabit network interface is CPU-limited to 25MB/s. How can I maximize the throughput?

I have a Acer Aspire R1600-U910H with a nForce gigabit network adapter. The maximum TCP throughput of it is about 25MB/s, and apparently it is limited by the single core Intel Atom 230; when the ...
0
votes
1answer
447 views

Why am I getting boot errors after a fresh Windows install?

I have a really strange problem. I have a new laptop (no guaranty) and everytime after a clean installation everything is perfectly fine. But when the laptop is powered off for a couple of hours I get ...
2
votes
2answers
5k views

Keyboard error or no keyboard present

I've been fighting with this for a couple of weeks when booting my PC: Error keyboard or no keyboard present CMOS checksum error -Default loaded And of course there is no way to go any further ...
4
votes
3answers
2k views

Is there anything like HashTab for Linux?

I've recently installed Linux, and I know that you can use "md5sum filename" in terminal, but on Windows there is an AMAZING software called HashTab that incorporates it into the shell. Its awesome, ...
2
votes
1answer
203 views

md5sum only new files?

I have a directory containing files and an md5sum.txt file. I add a file new files to the directory. I would like add md5sum sums for all files that are not in md5sum.txt. Is there a simple way to do ...
3
votes
4answers
4k views

Single unix command to correctly transfer a large file?

I am trying to transfer a large (~3GB) file between two unix machines. I can use scp or rsync, but sometimes the transfer is corrupted. (I have to check manually.) I can split the file into pieces ...
2
votes
2answers
241 views

HTTP downloader with good integrity(hash..probably md5) checker built in [closed]

I'm trying to download xcode v3.2 from the Apple Developer Connection website, but everytime I download the huge file, it fails to mount due to a checksum error. It's really frustrating! BitTorrent ...
3
votes
2answers
696 views

TCP Checksum, why?

Why does TCP need a checksum, when lower layers do integrity checks anyways (like Ethernet CRC)?
2
votes
4answers
217 views

Why would I check my download against a checksum provided by a mirror site?

I thought the point of distributing md5 checksums was so the end user could verify the integrity of the download. If a high traffic site points me to a mirror site for download, why would I want to ...