No space left on device - But disk and inodes are free

[zackiv31]

When running a simple tail command on /var/log/auth.log I get the following:

tail: cannot watch `auth.log': No space left on device

I've checked disk usage and inodes but there seems to be plenty:

zivester-pro:/var/log# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/md0              4.0G  2.6G  1.3G  68% /
tmpfs                  16K     0   16K   0% /USB
/dev/c/c              7.3T  6.4T  926G  88% /c

zivester-pro:/var/log# df -ih
Filesystem            Inodes   IUsed   IFree IUse% Mounted on
/dev/md0                 64K     19K     46K   30% /
tmpfs                   495K       1    495K    1% /USB
/dev/c/c                117M    1.2M    115M    2% /c

I have a ReadyNas Pro Pioneer edition w/ RAIDiator 4.2.27 and 4gb of ram. I've emptied /tmp/ and rebooted the device. If it's relevant I run Plex and Crashplan on the NAS.

[mdgm-ntgr]

# cat /proc/mounts
# dmesg | tail

[zackiv31]

zivester-pro:/var/log# cat /proc/mounts
rootfs / rootfs rw 0 0
proc /proc proc rw,relatime 0 0
sysfs /sys sysfs rw,relatime 0 0
tmpfs /dev tmpfs rw,relatime,size=10240k,mode=755 0 0
devpts /dev/pts devpts rw,relatime,mode=600 0 0
/dev/md0 / ext3 rw,relatime,errors=continue,barrier=0,data=ordered 0 0
tmpfs /ramfs ramfs rw,relatime 0 0
tmpfs /USB tmpfs rw,relatime,size=16k 0 0
usbfs /proc/bus/usb usbfs rw,relatime 0 0
/dev/c/c /c ext4 rw,noatime,nodiratime,barrier=1,stripe=64,data=ordered,jqfmt=vfsv1,usrjquota=aquota.user,grpjquota=aquota.group 0 0
nfsd /proc/fs/nfsd nfsd rw,relatime 0 0

zivester-pro:/var/log# dmesg | tail
ata3.00: configured for UDMA/133
ata3: EH complete
ata4.00: configured for UDMA/133
ata4: EH complete
ata5.00: configured for UDMA/133
ata5: EH complete
ata6.00: configured for UDMA/133
ata6: EH complete
TCP: Peer 38.81.66.30:443/45546 unexpectedly shrunk window 1290490566:1290496406 (repaired)
TCP: Peer 38.81.66.30:443/45546 unexpectedly shrunk window 1290490566:1290496406 (repaired)

[zackiv31]

I think my issue wasn't space related, by inotify/watch related. If I stopped plex I could successfully tail files. Temporary solution:

echo 900000 | sudo tee /proc/sys/fs/inotify/max_user_watches

permanent solution, add the following to /etc/sysctl.conf:

fs.inotify.max_user_watches=900000