Bei mir war es der jdownloader. Nach dessen Deinstallation war wieder alles ok.
Bei mir ist es das Logfile vom JDownloader. Aber den benutze ich ja ziemlich oft. Deshalb habe ich das Anlegen eines Logfiles deaktiviert. Allerdings muss man doch das bestehende Logfile löschen können oder nicht?
Edit: Scheint jetzt funktioniert zu haben. Aber anscheinend ist die Systempartition immernoch zu voll. Update lt. DSM nicht möglich.
Was ist mit den Logfiles: messages, auth.log und dms.log?
total 21180
-rw-rw---- 1 system log 103889 Oct 11 01:46 apparmor.log
lrwxrwxrwx 1 root root 46 Oct 5 2015 asterisk -> /var/packages/Asterisk/target/var/log/asterisk
-rw-rw---- 1 system log 6130899 Oct 12 12:12 auth.log
-rw-rw---- 1 system log 124931 Oct 12 11:55 bash_err.log
-rw-rw---- 1 system log 18579 Oct 12 12:19 bash_history.log
drwxr--r-- 2 root root 4096 Jun 29 2015 cluster
-rw-r--r-- 1 root root 33349 Oct 10 11:58 DeviceBusyList
-rw-r--r-- 1 root root 8419 Oct 10 12:02 DeviceBusyList2
-rw-r--r-- 1 root root 687 Oct 6 2015 disk_log.xml
-rw-r--r-- 1 root root 4209 Oct 11 01:42 disk_overview.xml
-rw-r--r-- 1 root root 549636 Oct 11 01:43 dmesg
-rw-r--r-- 1 root root 44216 Apr 21 20:53 dmesg.1.xz
-rw-r--r-- 1 root root 1253702 Oct 12 12:15 dms.log
-rw-r--r-- 1 root root 236782 Oct 3 10:28 dms.log.0.gz
-rw-r--r-- 1 root root 247679 Oct 2 22:20 dms.log.1.gz
-rw-r--r-- 1 root root 247132 Oct 2 21:53 dms.log.2.gz
-rw-r--r-- 1 root root 157649 Oct 2 21:43 dms.log.3.gz
drwx------ 2 root root 4096 Oct 5 2015 Docker
-rw-r--r-- 1 root root 62536 May 22 09:19 dpkg.log
-rw-r--r-- 1 root root 42190 May 22 09:19 dpkg_upgrade.log
-rw-rw---- 1 system log 5241 Oct 11 01:42 esynoscheduler.log
drwxr-xr-x 2 root root 4096 Oct 25 2015 httpd
-rw-rw---- 1 system log 541443 Oct 11 01:42 iscsi.log
-rw-rw---- 1 system log 475165 Oct 11 07:57 kern.log
drwxr-xr-x 2 admin users 4096 Jul 14 00:48 lighttpd
-rw-r--r-- 1 root root 30 Oct 6 2015 lvm_lv_create_log
-rw-rw---- 1 system log 8019232 Oct 12 11:36 messages
-rw-rw---- 1 system log 164552 Jul 3 19:42 messages.1.xz
-rw-rw---- 1 system log 167200 Jun 26 06:00 messages.2.xz
-rw-rw---- 1 system log 167592 Jun 17 13:01 messages.3.xz
-rw-rw---- 1 system log 164692 Jun 11 09:42 messages.4.xz
-rw-r--r-- 1 root root 0 Oct 6 2015 mount.log
drwxr-x--- 2 http root 4096 Feb 18 2016 nginx
-rw-rw-rw- 1 root root 156750 Oct 11 01:48 opentftp.log
-rw-r--r-- 1 root root 0 Oct 6 2015 partition
-rw------- 1 root root 14090 Oct 11 01:46 php-fpm.log
-rw-rw---- 1 system log 191007 Oct 11 08:27 postgresql.log
-rw-rw---- 1 system log 299107 Oct 12 11:36 router.log
drwxr-xr-x 2 root root 4096 Oct 5 2015 samba
-rw-rw---- 1 system log 631300 Oct 12 12:07 scemd.log
drwxr-x--- 2 root root 4096 May 9 21:34 selfcheck
-rw-rw-rw- 1 root root 6706 Oct 11 01:42 space_operation_error.log
-rw-r--r-- 1 root root 2020 Oct 11 01:42 synocmsclient.log
-rw-r--r-- 1 root root 75944 Oct 11 00:14 synocrond-execute.log
-rw-rw---- 1 system log 8429 Oct 11 01:42 synocrond.log
-rw-r----- 1 root root 39121 Mar 25 2016 synodtv.log
-rw-rw---- 1 system log 15382 Oct 11 01:39 synofeasibilitycheck.log
-rw-r--r-- 1 root root 8239 Apr 21 20:52 synoinfo.conf.bad
drwxr-x--- 2 root root 4096 Oct 12 12:12 synolog
-rw-rw---- 1 system log 3027 Oct 11 01:39 synopoweroff.log
-rw------- 1 root root 13683 Oct 11 01:42 synorelayd.log
-rw-rw---- 1 system log 495415 Oct 12 11:36 synoservice.log
-rw-rw---- 1 system log 104760 Jul 24 23:59 synoservice.log.1.xz
-rw-rw---- 1 system log 103560 Jun 28 06:03 synoservice.log.2.xz
-rw-rw---- 1 system log 101460 Jun 3 09:30 synoservice.log.3.xz
-rw-rw---- 1 system log 101320 Apr 30 06:44 synoservice.log.4.xz
-rw-rw---- 1 system log 88624 Mar 31 2016 synoservice.log.5.xz
-rw-rw---- 1 system log 707 Oct 11 01:39 synotifyd.log
-rw-r--r-- 1 root root 2949 May 22 09:19 synoupdate.log
-rw-rw---- 1 system log 29901 Oct 11 01:41 syslog.log
drwxr-xr-x 2 root root 4096 Oct 11 01:39 upstart
