I run Ubuntu Linux and use backup script that copies things over using rsync:
rsync -rc /home/user/source /media/nas/destination
rsync -r /home/user/source /media/nas/destination
However - it takes approximately 2.5 hours every day (i run this every day), to get it done. There is approximately 76 Gb of data over 1Gbit lan. So - basically - rsync just doesn't skip existing files in destination - it just copies everything over and over again.
I assume that the problem lies in NAS (d-link 321) and that it's a samba share that doesn't support unix persmission system - right? So this way rsync can't distinguish old files from new files - right? I've tried rsync with -c parametr (skip based on checksum, not mod-time & size) but still no dice, still takes 2.5 hours.
Can anybody suggest the way of syncing appx 70-80 Gb of data that doesn't ivolve "dumb" copying of everything every time?
well. no luck. I've erased destination directory and and ran this twice:
rsync -r --times /home/user/source /media/nas/destination
It still took 2.5 hours both times. so it copies everything twice.
mmm. I went deeper to investigate this problem. And it looks like rsync doesn't preserve times. I've ran stat command on some files from source and destination - and Access, Modify, Change times aren't preserved on destination. I have no clue as to why does this happen... Any other suggestions? P.s. I relatively new to Linux - sio it can be something really dumb and silly:)
UPDATE 2 Resolved: problem as I realized stemmed from me mounting shares incorrectly. I've been mounting them like this (in /etc/fstab):
//192.168.10.199/Volume_1 /media/Volume_1 cifs guest,rw,iocharset=utf8,file_mode=0777,dir_mode=0777 0 0
And this is what worked:
//192.168.10.199/Volume_2 /media/Volume_2 cifs username=sam,password=some_password,uid=developer,gid=developer,_netdev 0 0
Rsync preserves times now and only takes 3 minutes!