[Samba] INTERNAL ERROR and PANIC: internal error - samba version 4.8.2

[Marcio Souza]

Hello everyone, I apologize, because I'm using google translator
because I do not write well in English. But I will post the problem to
see if you can help me, I have samba 4.8.2 running here on the network
for about 60 days and in the last 15, he started to present the error
"INTERNAL ERROR: Signal 11 in pid 5301 (4.8.2) and PANIC: internal
error "and notice that the dns service" internal dns "stops working.
When executing the "netstat -ant" I only see port ": 53". I noticed
that the problem began to occur as the number of hosts and users
logged into the domain increased. Today, there are approximately 120
hosts. Follow the log for analysis, thank you for the force.



Samba 4.8.2
Ubuntu
Linux dc01smbrec 4.4.0-130-generic # 156-Ubuntu SMP Thu Jun 14
08:53:28 UTC 2018 x86_64 x86_64 x86_64 GNU / Linux

Log error:

[2018/08/02 15:14:53.402161,  1] ../lib/ldb-samba/ldb_wrap.c:77(ldb_wrap_debug)
  ldb: ldb_handler_fold: unable to casefold string [▒g▒▒g▒]
[2018/08/02 15:14:53.402236,  1] ../lib/ldb-samba/ldb_wrap.c:77(ldb_wrap_debug)
  ldb: ldb_handler_fold: unable to casefold string [▒g▒▒g▒]
[2018/08/02 15:14:53.402274,  1] ../lib/ldb-samba/ldb_wrap.c:77(ldb_wrap_debug)
  ldb: ldb_handler_fold: unable to casefold string [▒g▒▒g▒]
[2018/08/02 15:14:53.402310,  0] ../lib/util/fault.c:78(fault_report)
  ===============================================================
[2018/08/02 15:14:53.402388,  0] ../lib/util/fault.c:79(fault_report)
  INTERNAL ERROR: Signal 11 in pid 6182 (4.8.2)
  Please read the Trouble-Shooting section of the Samba HOWTO
[2018/08/02 15:14:53.402533,  0] ../lib/util/fault.c:81(fault_report)
  ===============================================================
[2018/08/02 15:14:53.402664,  0] ../lib/util/fault.c:151(smb_panic_default)
  PANIC: internal error
[2018/08/02 15:14:53.550223,  0]
../source4/smbd/process_standard.c:158(standard_child_pipe_handler)
  standard_child_pipe_handler: Child 6182 (dns) terminated with signal 6
[2018/08/02 15:20:31.004389,  0] ../source4/smbd/server.c:466(binary_smbd_main)