Volume: System volume root's usage is 91%

[ors]

Hi recently I've been alerted with the message that System volume root's usage is 91%. I've tried SSH and apt-get clean and apt-get autoclean, removed syncthing, plex and transmission, but the issue remains. Running OS6 6.9.3

Please help

root@verzamelbox:~# df -h
Filesystem      Size  Used Avail Use% Mounted on
udev             10M  4.0K   10M   1% /dev
/dev/md0        4.0G  3.7G   27M 100% /
tmpfs           998M     0  998M   0% /dev/shm
tmpfs           998M  3.6M  994M   1% /run
tmpfs           499M  1.5M  498M   1% /run/lock
tmpfs           998M     0  998M   0% /sys/fs/cgroup
/dev/md127      1.9T  897G  962G  49% /data
/dev/md127      1.9T  897G  962G  49% /apps
/dev/md127      1.9T  897G  962G  49% /home
/dev/md127      1.9T  897G  962G  49% /var/ftp/media

root@verzamelbox:~# du -csh /var/lib/*
38M     /var/lib/apt
4.0K    /var/lib/btrfs
0       /var/lib/clamav
20K     /var/lib/connman
0       /var/lib/dbus
18M     /var/lib/dpkg
0       /var/lib/ftp
0       /var/lib/gconf
0       /var/lib/initscripts
0       /var/lib/insserv
4.0K    /var/lib/libuuid
4.0K    /var/lib/mdadm
0       /var/lib/misc
30M     /var/lib/mysql
8.0K    /var/lib/nfs
0       /var/lib/nut
24K     /var/lib/pam
0       /var/lib/php5
4.0K    /var/lib/python-support
4.0K    /var/lib/random-seed
4.0K    /var/lib/readyNASVault.version
0       /var/lib/replisync
2.6M    /var/lib/samba
0       /var/lib/snmp
0       /var/lib/sudo
124K    /var/lib/systemd
124K    /var/lib/ucf
0       /var/lib/update-rc.d
0       /var/lib/urandom
468K    /var/lib/usbutils
0       /var/lib/vim
89M     total

[ors]

Been reading up on similar topics. Using the following

--- 8< ---

# mount --bind / /mnt

Then 

cd /mnt

du -csh *

--- 8< ---

I've had a folder called 'media' with 2.5G in size that contained a subfolder USB_HDD4 although I had no external media attached to the NAS. Deleting the media folder with

rm -Rf media

cleared the root folder : root@verzamelbox://# df -h
Filesystem      Size  Used Avail Use% Mounted on
udev             10M  4.0K   10M   1% /dev
/dev/md0        4.0G  1.2G  2.5G  33% /
tmpfs           998M     0  998M   0% /dev/shm
tmpfs           998M  3.6M  994M   1% /run
tmpfs           499M  1.5M  498M   1% /run/lock
tmpfs           998M     0  998M   0% /sys/fs/cgroup
/dev/md127      1.9T  897G  962G  49% /data
/dev/md127      1.9T  897G  962G  49% /apps
/dev/md127      1.9T  897G  962G  49% /home
/dev/md127      1.9T  897G  962G  49% /var/ftp/media

Hope the issue doesn't return 😕

[StephenB]

---

@ors wrote:

I've had a folder called 'media' with 2.5G in size that contained a subfolder USB_HDD4 although I had no external media attached to the NAS.

---

The NAS has several folders in the OS partition that are intended as mount points. They are supposed to be empty, but if they aren't the mounts make them hard to examine them. The mount --bind / /mnt lets you examine the full OS partition without those mounts hiding what's "underneath" them. 

In this particular case, the USB drive was mounted to media folder.  If something goes wrong with that mount and a backup job runs anyway, then the backup is done to the OS partition, and not the intended target.  Although that is pretty rare, when it does happen it can quickly fill up the OS partition. 

[ors]

Somehow I'm unable to connect any kind of external storage to my Readynas. I get an error that the filesystem is not recognized. Even formatting the drive with FAT32 with PC and reinsert doesn't help. I'm afraid that the deleted folder (see post 1) is the culprit, but no idea how to fix this.

Bit hesitant to flash or reinstall firmware as backup drive can't be used when things go south.

[StephenB]

---

@ors wrote:
Somehow I'm unable to connect any kind of external storage to my Readynas. I get an error that the filesystem is not recognized.

---

Did you try formatting it from the NAS volume page?

Also, are you using a drive is powered through the USB port?  If so, try one that is powered separately.

[mdgm-ntgr]

You shouldn't have deleted the media folder, just the erroneous USB folder inside it.

Perhaps try recreating the media folder

# mkdir /media
# chmod 755 /media