QUESTION: is it possible to mount an ext4 NFS share (e.g. from a QNAP NAS, they have chosen ext4 as defaults... i am not shure if you can actually change that) into a ext3 filesystem?
What additional info do you need to debug the problem?
here is what i have so far:
NFS is pretty fast protocol for accessing files - i like that.
It uses less overhead than SMB/CIFS and therefore acchieves greater performance - also - there are many versions of SMB in many versions of Windows that might not be compatible with each other.
Is that true for nfs as well? (could be one source of the problems)
method1) rsyncing to a nfs-mounted qnap nas went with 20,7 MBytes/sec.
method2) while directly ssh-rsyncing to qnap works only with 3-4 MByte/sec (server is CPU not very performant „Feroceon 88F6281 rev 1 (v5l) @ 1.2 GHz with BogoMIPS : 1196.85“ according to cat /proc/cpu, can’t decrypt ssh-traffic any faster).
i lost data because something seems to go wrong during that transfer process.
The files get corrupted.
It does not matter if i directly copy the files into the mounted folder or rsync it into that folder... (directly ssh-rsyncing to qnap works fine).
this leaves me a little baffled.
is nfs capable of bridging different filesystems or not?
server: QNAP TS-219 QTS 4.1.4 Build 20150522
uname -a; # QNAP uses EXT4
Linux QNAP 3.4.6 #1 Fri May 22 07:56:30 CST 2015 armv5tel unknown
mount; # DATA is ext4
/dev/md0 on /share/MD0_DATA type ext4 (rw,usrjquota=aquota.user,jqfmt=vfsv0,user_xattr,data=ordered,nodelalloc,noacl)
nfsd on /proc/fs/nfsd type nfsd (rw)
cat /proc/fs/nfsd/versions
+2 +3 -4 -4.1
cat /proc/fs/nfs/exports
# Version 1.1
# Path Client(Flags) # IPs
/share/MD0_DATA/DATA *(rw,insecure,no_root_squash,async,wdelay,no_subtree_check,uuid=60dd2e14:9a01561b:00000000:00000000)
dmesg|grep nfs
[ 66.638725] Installing knfsd (copyright (C) 1996 okir@monad.swb.de).
[ 214.072501] NFSD: Using /var/lib/nfs/v4recovery as the NFSv4 state recovery directory
lsmod | grep nfs
nfsd 231700 12 fnotify, Live 0xbf349000
exportfs 2885 1 nfsd, Live 0xbf345000
nfs 251340 0 - Live 0xbf2f2000
auth_rpcgss 30572 2 nfsd,nfs, Live 0xbf2e4000
lockd 59814 2 nfsd,nfs, Live 0xbf2cd000
sunrpc 167759 14 nfsd,nfs,auth_rpcgss,lockd, Live 0xbf291000
client: uname -a; # it's a pretty up to date debian system USING EXT3 Linux debian 3.16.0-4-686-pae #1 SMP Debian 3.16.36-1+deb8u1 (2016-09-03) i686 GNU/Linux
mount; # client is using ext3
/dev/sda5 on / type ext3 (rw,relatime,errors=remount-ro,data=ordered)
dmesg|grep nfs
[ 2.517324] FS-Cache: Netfs 'nfs' registered for caching
[ 2.522955] Installing knfsd (copyright (C) 1996 okir@monad.swb.de).
dmesg|grep NFS
[ 2.509406] RPC: Registered tcp NFSv4.1 backchannel transport module.
[13274.540947] NFS: Registering the id_resolver key type
How share was mounted:
# command used to mount the NFS share
mount 192.168.1.123:/DATA /mnt/qnap;
192.168.1.123:/DATA on /mnt/qnap type nfs (rw,relatime,vers=3,rsize=32768,wsize=32768,namlen=255,hard,proto=tcp,timeo=60 0,retrans=2,sec=sys,mountaddr=192.168.1.123,mountvers=3,mountport=48394,mountproto=udp,local_lock=none,addr=192.168.1.123)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,relatime)
„This is a much-improved Linux NFS server with support for NFSv3 as well as NFSv2. NFSv4 is being worked on. These patches are considered stable and are indeed shipping with most distributions. The stock Linux 2.2 NFS server can’t be used as a cross-platform file server“
I previously lost (mostly backup)data because of ext4 partitions going corrupt on a 800€ „CHEAP TAIWANESE“ QNAP NAS.
So QNAP seems to not do enough testing.
„GOOD JOB GUYS“.
You just lost a customer - forever.
Article about the problem: http://dwaves.de/2016/09/21/about-nfs-problems-with-qnap-nfs-server-and-rsync/
