USB supported file systems, DL4100

Since NTFS has an inadequate path length limit on windows, I must attach an external drive formatted with a more suitable file system. Please spare me any flames wrt which is the best file system, I really don’t care, and that’s not the point here. A MyBook 6TB that is dedicated to the purpose has been formatted with ext4 in the “big” flavor (the default for that size) on a separate Linux machine. When connected to the front USB3 port of a DL4100, the DL4100 claims the file system of this drive is an unsupported file system. That sounds just weird, as ext4 is the default for many linux installations. Anyway, I can compromise, but I am becoming increasingly frustrated with my DL4100 for a number of reasons, of which this is one.

Anyone knows for a fact which file systems are supported for connecting an external USB drive of 6TB in read write mode? Or for a smaller drive?

Hi @asq

My Cloud OS supports almost all file systems except exFAT. What options you have used during the formating of your Ext4? Of course, Ext4 is supported by the DL but it depends on what specialties you have included. The 6 TB drive should be formatted with 4096 Byte/Sector as this is a 4Kn drive.


your attention is surely appreciated! This pickle is becoming, hmm, frustrating. Initial ext4 misadventure:

alsq@xulvm:~$ sudo mke2fs -L ext4wd6TB -t ext4 -v /dev/sdb1

after the ext4 misadventure I had two more failures with what I thought was a less challenging ext3 attempt. These are the two formatting lines that failed.

alsq@xulvm:~$ sudo mke2fs -L ext3wd6TB -m 0 -t ext3 -v /dev/sdb1

alsq@xulvm:~$ sudo mke2fs -L ext3wd6TB -m 0 -r 0 -t ext3 -T default -v /dev/sdb1

the difference between using or not using -T default is in the inode ratio; /etc/mke2fs.conf for default uses on my system the following:

base_features = sparse_super,filetype,resize_inode,dir_index,ext_attr
default_mntopts = acl,user_xattr
enable_periodic_fsck = 0
blocksize = 4096
inode_size = 256
inode_ratio = 16384

ext3 = {
features = has_journal
ext4 = {
features = has_journal,extent,huge_file,flex_bg,uninit_bg,dir_nlink,extra_isize
auto_64-bit_support = 1
inode_size = 256

whereas the “big” option (what mke2fs picks for 6TB drives) shows

big = {
inode_ratio = 32768

so, blocksize is 4096 either way. In case it matters: the system used for formatting is Ubuntu trusty (14.04)

alsq@xulvm:/media$ uname -a
Linux xulvm 3.13.0-79-generic #123-Ubuntu SMP Fri Feb 19 14:27:58 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

Unfortunately I cannot ssh into the DL4100 because the latest firmware update fried my sshd, not sure why. (It was working before the update, curse my eagerness to stay current.) Tried the usual (restart, etc. etc.) to no avail. Grrr… When plugging the USB3 drive so formatted under 14.04 Ubuntu into the front of the DL4100 after a while the DL4100 gets all excited flashing red all over and protests “Unsupported file system” in the LCD window. If I can’t find a way out, I’m afraid I’m going to have to do a dump of (sigh) 5-6TB over the network to a more reasonable host. Not sure what I will do to my persnickety DL4100 afterward.

Can you recommend a format line that will work?
Or did the latest upgrade fry more than just my beloved sshd and ssh access?