Latest observation from my side is that lxc-console hangs as well. During login via lxc-console it hangs after motd

lxc-console -n kjell

Connected to tty 1
Type <Ctrl+a q> to exit the console, <Ctrl+a Ctrl+a> to enter Ctrl+a itself

Debian GNU/Linux 8 kjell tty1

kjell login: NNNN
Password: 
Last login: Mon Apr 25 15:56:13 CEST 2016 from 151.156.192.9 on pts/4
Linux kjell 4.4.0-21-generic #37-Ubuntu SMP Mon Apr 18 18:33:37 UTC 2016 x86_64

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.


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I listed the processes and found that even CRON was stucked. Se list below

ps aux
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root         1  0.0  0.0  28208  3316 ?        Ss   Apr23   0:01 /sbin/init
root        38  0.0  0.0  32968  4372 ?        Ss   Apr23   0:00 /lib/systemd/systemd-journald
root        96  0.0  0.0  27476  1432 ?        Ss   Apr23   0:00 /usr/sbin/cron -f
root       102  0.0  0.0  12664  1236 tty3     Ss+  Apr23   0:00 /sbin/agetty --noclear tty3 linux
root       103  0.0  0.0  12664  1212 tty2     Ss+  Apr23   0:00 /sbin/agetty --noclear tty2 linux
root       104  0.0  0.0  12664  1172 tty4     Ss+  Apr23   0:00 /sbin/agetty --noclear tty4 linux
root       105  0.0  0.0  63316  2268 tty1     Ss+  Apr23   0:00 /bin/login --      
root       106  0.0  0.0  14236  1272 console  Ss+  Apr23   0:00 /sbin/agetty --noclear --keep-baud console 115200 38400 9600 vt102
root       121  0.0  0.0   8440  1160 ?        S    Apr23   0:00 /usr/sbin/syslogd --no-forward
Debian-+   364  0.0  0.0  53248  2260 ?        Ss   Apr23   0:00 /usr/sbin/exim4 -bd -q30m
root      2284  0.0  0.0  42336  1960 ?        S    Apr25   0:00 /usr/sbin/CRON -f
root      2475  0.0  0.0  42336  1960 ?        S    Apr25   0:00 /usr/sbin/CRON -f
root      2686  0.0  0.0  42336  1960 ?        S    Apr25   0:00 /usr/sbin/CRON -f
root      2789  0.0  0.0  42336  1960 ?        S    Apr25   0:00 /usr/sbin/CRON -f
root      2794  0.0  0.0  42336  1960 ?        S    Apr25   0:00 /usr/sbin/CRON -f
root      2813  0.0  0.0  55184  4056 ?        Ss   Apr25   0:00 /usr/sbin/sshd -D
root      2864  0.0  0.0  42336  1960 ?        S    Apr25   0:00 /usr/sbin/CRON -f
root      2869  0.0  0.0  42336  1960 ?        S    00:17   0:00 /usr/sbin/CRON -f
root      2874  0.0  0.0  42336  1960 ?        S    01:17   0:00 /usr/sbin/CRON -f
root      2879  0.0  0.0  42336  1960 ?        S    02:17   0:00 /usr/sbin/CRON -f
root      2884  0.0  0.0  42336  1960 ?        S    03:17   0:00 /usr/sbin/CRON -f
root      2889  0.0  0.0  42336  1960 ?        S    04:17   0:00 /usr/sbin/CRON -f
root      2894  0.0  0.0  42336  1960 ?        S    05:17   0:00 /usr/sbin/CRON -f
root      2900  0.0  0.0  42336  1960 ?        S    06:17   0:00 /usr/sbin/CRON -f
root      2901  0.0  0.0  21888  2668 ?        Ss   06:20   0:00 /bin/bash
root      2934  0.0  0.0  19100  1628 ?        R+   06:21   0:00 ps aux
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I narrowed it down to syslogd process.  I restarted inetutils-syslogd and now the container behaves as expected again.
Now we need to trackdrown what happends with syslogd processes in my containers.