Server Fault
Server Fault

Questions tagged [checksum]

76 questions
42
votes
2 answers

How to verify a file using an asc signature file?

As an example, this project offers an *.asc file with a PGP signature to verify the contents of the download (as opposed to a checksum, you can see the empty column): https://ossec.github.io/downloads.html How would I use this file? I tried gpg…
user8897013
  • 533
35
votes
1 answer

Too many incorrect checksum errors in TCPDUMP

I find too many incorrect checksum errors from a TCPDUMP done on a GNU Linux 64bit server. There are close to 50% incorrect chekcsums in the export? cksum 0xe61f (incorrect (-> 0x8c37) How can we interpret this data? Does it affect performance a…
Vishal
  • 455
21
votes
4 answers

Creating a tar file with checksums included

Here's my problem : I need to archive to tar files a lot ( up to 60 TB) of big files (usually 30 to 40 GB each). I would like to make checksums ( md5, sha1, whatever) of these files before archiving; however not reading every file twice (once for…
wazoox
  • 7,156
19
votes
4 answers

How to get checksum data integrity on ext4?

On file systems like btrfs you can preform a scrub, which will go though all the data to see if the data still matches the file system checksum. I would like to check the data on ext4 if it is correct before a backup. Question ext4 doesn't have file…
Sandra
  • 10,711
  • 41
  • 120
  • 173
11
votes
2 answers

How can I tell which ZFS snapshots are affected by an error?

A recent scrub of my ZFS pool uncovered one error: $ zpool status -v rpool pool: rpool state: ONLINE status: One or more devices has experienced an error resulting in data corruption. Applications may be affected. action: Restore the…
Ryan C. Thompson
  • 649
8
votes
1 answer

ZFS vdevs accumulate checksum errors, but individual disks do not

I'm running a vendor-specific derivative of FreeNAS 9.3. My trouble started when I installed a new JBOD chassis to add two new vdevs into my pool, and the chassis had a bad board. During this time, I was seeing SAS power errors on the drives on the…
user260467
  • 375
8
votes
3 answers

Checksumming to verify rsync transfers

So rsync runs some checksums in the course of deciding what to transfer (i.e. what blocks within a file). But is there any reason to trust the file you end up with on the receive side any more than you would for a normal network transfer? Should I…
Chinasaur
  • 273
6
votes
2 answers

zfs checksum error in raidz1 vdev but not in disk

I am backing up data stored in a zpool consisting of a single raidz vdev with 2 hard disks. During this operation, I got checksum errors, and now the status looks as follows: pool: tmp_zpool state: ONLINE status: One or more devices has…
Matei David
  • 231
  • 2
  • 6
6
votes
1 answer

Is it possible to access the ZFS checksums to compare files

I have a FreeNAS 8 machine (FreeBSD 8.2-RELEASE-p1) with two different shares on it. I'm migrating files from Share1 to Share2. The Shares have different directory structures and naming conventions. I'm looking for a way to verify that a file on…
Alan W. Smith
  • 259
5
votes
1 answer

Does NTFS / Windows as OS performs checksumming on file movement operations by default?

That's what I can't find Does NTFS / Windows as OS performs checksumming on file movement operations by default? alike ZFS or somehow else...
cnd
  • 155
4
votes
0 answers

btrfs, Force bad checksum recalculation

A large, USB-connected HDD with btrfs contains a 1TB file (a disk image). The first btrfs scrub after writing that file found 3 logical bad blocks developed somewhere in the middle of that file: [ 7702.964265] BTRFS warning (device sdd1): checksum…
liori
  • 777
4
votes
1 answer

What would cause a successful file transfer to have checksums not match?

After very large file transfers (this only happens with 10gig+ files) to a specific system, the receiving system would have a mismatched checksum of the file. The transfer seems to have happened sucessfully, the files match in terms of size to the…
Mike D
  • 41
3
votes
1 answer

Does ZFS, using default settings, use more physical space than ext4 for the same amount of data?

I'm currently considering a switch from ext4 to ZFS and am having trouble finding information about whether or not it uses more or less space to store the same amount of data as ext4. My understanding is that it uses checksums for data integrity,…
Curtis
  • 513
3
votes
2 answers

Why isn't TCP corruption more noticeable?

First of all, apologies if this seems a somewhat simplistic question. According to this answer, TCP packets are corrupted all the time without the checksum catching it. If this happens so often, why is it not more noticeable? Shouldn't this result…
dt-rush
  • 33
3
votes
0 answers

Get checksums of all packages on a yum repo server

I have a server I'm using as a yum reposerver. I've mirrored all the packages I want, and added additional packages in different folders. I've created multiple repos with the createrepo command. There are now multiple levels of folders with a…
Carrot
  • 266
1
2 3 4 5 6