Lewis' Blog Tales from the trenches of information technology

Enabling Extended Attribute support in a Thecus N2200-EVO

In a related post to my notes on enabling extended attribute support for the Synology DiskStation DS212j, I've managed to accomplish the same task somewhat more elegantly in the Thecus offering. As compared to the Synology 2-bay unit, the Thecus is about the same size and price and offers similar functionality, with the added benefit of hot-swappable drive bays (though the "hot-swappable" part remains something to be proven to me; let's jet say that they are front-accessible, without screws to remove to extricate the drive caddies from the chassis). Getting EA support was considerably easier than with the Synology, as well.

Extended Attributes

To keep this post short and to the point, I'll simply refer to my previous post for more detail on extended attributes. Needless to say, on OS/2 or eCS, when you need them, you need them, and there's no sense having a sharable storage device when you'll be losing a good portion of your metadata in the process of backing things up or otherwise saving or modifying saved files on the device.

Extended Attributes in the XFS Filesystem

Unlike the DiskStation, Thecus chose a much more robust filesystem for their NAS units, namely, XFS. XFS has native support for EAs, with nothing to configure to enable it at mount time. EA support in XFS, unlike that in ext3/4, is of considerable size (note Dave's comment to my previous article, here).

Enabling Extended Attribute Support in SAMBA

In the DiskStation, configuration data is stored in a single Postgres database. Synology does not seem to provide credentials to allow access to the db for modification, so cracking it becomes yet another obstacle. Thecus chose instead to use multiple sqlite database files, making configuration changes much more accessible.

Ultimately, we want to end up with the parameter:

ea support = yes

appended to each share defined in the live smb.conf. The trick is to add this parameter and value to the sqlite database (smb.db) so that when the conf is built at sambe startup/restart, it just goes in along with everything else. Thus, from an ssh prompt, we do:

N2200EVO:~# sqlite /raid0/sys/smb.db "insert into smb_share (k,v,m) values ('ea support','yes','0')"

(some syntax reference, here) after which, we simply restart the samba service:

N2200EVO:~# /img/bin/rc/rc.samba restart

Done.

Persistance

Because we have added the new parameter to the database itself, there is no need to make on-the-fly changes to the configuration files once they have been created after each system start. This stands in stark contrast to the kludge required for the DiskStation and for many other similar devices.

References

Thecus N41000PRO Tweaking Samba
Thecus Support Forum Thread: I cannot change smb.conf

Last Updated on February 13th, 2014 by LewisR