On Wed, Jun 2, 2010 at 10:47 PM, Sean Crago <cragos@gmail.com> wrote:
If the list is coming back to life, then I've got a weird but hopefully simple problem for you:

I've got a Synology DiskStation DS209 NAS that's giving me erroneous free space readings, or erroneous du output. On installation, it dedicated 2.4GB to its root partition /dev/md0 and according to du -cx / is using less than 587192K of that space. Unfortunately, however, df says it's full. 

bash-3.2# df -k
Filesystem           1K-blocks      Used Available Use% Mounted on
rootfs                 2451064   2425764         0 100% /
/dev/root              2451064   2425764         0 100% /

bash-3.2# mount
/dev/md0 on / type ext3 (rw,data=ordered)

As a result, any number of apps from the stock firmware are prevented from running and those that do hobble along spam the logs to the point of uselessness w/complaints. The catch? I can't find a safe way to fsck it. Conventional shutdown commands to force a fsck aren't an option/are just plain missing on the box. Using tune2fs to set the check interval ridiculously low to force a check upon reboot similarly didn't work. Unfortunately, the ARM-based architecture also doesn't support booting to a removable USB device, knocking out the only other safe way I can think of to fsck it. Pop new firmware on to start from scratch? I'd love to at this point, but the firmware installation process requires 1024 megs of free disk space.

Thoughts?  Any ideas on how to safely get it cleaned up and accurately reporting its free space while the root filesystem is live and booted?

-Sean

Oh, and I really doubt this changes the solution, but for full disclosure's sake:

Last change I made to the system was to install the ipkg for mlocate, which stores its small 500k db on a different partition. Also, power situation is abysmal here, and I'm not convinced it's shutting down properly when it detects that it's on UPS power.