rsync to CIFS, iSCSI or module?

[meu]

Hi,
I want to backup my files. I decided to use rsync client (cwRsync_4.0.5) on windows 7 to push files to FreeNAS.
Is there a difference between sending files using rsync client to CIFS share (as mapped drive) or iSCSI target or Rsync module?

my FreeNAS is: 8.3.1-RELEASE-p2-x64

 

[JaimieV]

I don't know about iSCSI target, but sending to an rsync module is preferable to using a CIFS share. If you use a module, each end will calculate hashes for files and only transfer files that have changed; if you use a share then the client end has to read *both* ends to do that comparison, leading to many times the network traffic and lots slower.

I'd guess iSCSI target would be similar to CIFS share, with the client (and network) doing all the work.

 

[HolyK]

Yes, there is difference.

In case of rsync module, transfer will be done via rsync protocol (so no CIFS/iSCSI). Like JaimieV said, this is preferred and much faster since you will "sync" only the difference. This works also for big files. For example while syncing 1GB file, rsync will split the file into small chunks on both sides, then hash for each chunk will be calculated and compared. In case of difference, only changed chunks will be transferred. Just keep on mind that not all clients supports partial sync. cwRsync support this.

For CIFS/iSCSI sync, i guess there will be just a simple timestamp / filesize / filecontain compare and in case of difference, old file will be fully overwritten by new version ... this will be much slower in case of big files ... i am not sure with this but i really don't think that partial sync will work here ...


Or, you could use some 3rd party software and schedule automatic backups (via CIFS, FTP, ... whatever). O&O DiskImage, Acronis TrueImage, Paragon Backup, ... etc...

 

[JaimieV]

HK - you can use rsync like cp, from one local (or mounted) directory to another, but as I've said above if you're rsyncing to a mounted directory you're worse off than if you were rsyncing to the same directory except as a module.

 

[HolyK]

2 JaimieV: Ok, thanks. I will take a look on it. I was testing rsync a while ago and there was a huge time difference between rsync via module and rsync to mounted CIFS share. I was not looking for the reason since i choose another backup method.