Hi, I want to use samba as AD on SLES 11 SP3. And I can make samba 4.5.x into some rpms which works well. Recently I try to build samba 4.8.0 using my spec file which works well on samba4.5.x. But when I test these rpms there is a problem. When I use ldap to access the domain to query some domain info, it remains me the directory service is not operational. This problem also appears in samba4.7.6 with my spec file.Besides, I tried to use AD Explorer to connect the AD. It also failed with “this directory service is unavailable”. And here are my configure options in spec file: PATH_OPTS="\ --enable-fhs \ --with-lockdir=%{_localstatedir}/cache/samba \ --prefix=%{_prefix} \ --exec-prefix=%{_exec_prefix} \ --bindir=%{_bindir} \ --sbindir=%{_sbindir} \ --sysconfdir=%{_sysconfdir} \ --datadir=%{_datadir} \ --includedir=%{_includedir} \ --libdir=%{_libdir} \ --libexecdir=%{_libexecdir} \ --localstatedir=%{_localstatedir} \ --sharedstatedir=%{_sharedstatedir} \ --mandir=%{_mandir} \ --infodir=%{_infodir} \ --with-pammodulesdir=/%{_lib}/security \" BUILD_OPTS="\ --disable-rpath-install \ --bundled-libraries=ALL \ %if %{make_devel} --enable-developer \ --picky-developer \ --enable-krb5developer \ %endif" CONF_OPTS="\ --enable-cups \ --enable-gnutls \ --with-acl-support \ --with-automount \ --with-pam \ --without-profiling-data \ --with-quotas \ --with-syslog \ --with-utmp \ --with-winbind \ --with-ads \ --with-dnsupdate \ --with-cluster-support \ %if %{with_libarchive} --with-libarchive \ %else --without-libarchive \ %endif %if %{make_dmapi} --with-dmapi \ %else --without-dmapi \ %endif --with-shared-modules=%{shared_modules} \" ./configure $PATH_OPTS $BUILD_OPTS $CONF_OPTS This is my smb.conf : [global] bind interfaces only = Yes interfaces = 8.22.145.173 127.0.0.1 log file = /var/FusionAccess/LiteAD/log.samba log level = 2 max log size = 15000 netbios name = SAMBATEST2 realm = TESTSAMBA476.HAUWEI.COM server role = active directory domain controller workgroup = TESTSAMBA476 idmap_ldb:use rfc2307 = yes ldap server require strong auth = no load printers = no printing = bsd printcap name = /dev/null disable spoolss = yes [netlogon] path = /var/lib/samba/sysvol/testsamba476.hauwei.com/scripts read only = No [sysvol] path = /var/lib/samba/sysvol read only = No In log.samba I found those when I use ldap to access the domain: [2018/04/11 15:31:18.303677, 0] ../auth/ntlmssp/ntlmssp_sign.c:236(ntlmssp_check_packet) NTLMSSP NTLM2 packet check failed due to invalid signature! [2018/04/11 15:31:18.303917, 2] ../source4/smbd/process_standard.c:473(standard_terminate) standard_terminate: reason[ldapsrv_call_loop: tstream_read_pdu_blob_recv() - NT_STATUS_IO_DEVICE_ERROR] [2018/04/11 15:31:18.307704, 2] ../source4/smbd/process_standard.c:157(standard_child_pipe_handler) Child 24315 () exited with status 0 [2018/04/11 15:31:18.347855, 0] ../auth/ntlmssp/ntlmssp_sign.c:236(ntlmssp_check_packet) NTLMSSP NTLM2 packet check failed due to invalid signature! [2018/04/11 15:31:18.348237, 2] ../source4/smbd/process_standard.c:473(standard_terminate) standard_terminate: reason[ldapsrv_call_loop: tstream_read_pdu_blob_recv() - NT_STATUS_IO_DEVICE_ERROR] [2018/04/11 15:31:18.352456, 2] ../source4/smbd/process_standard.c:157(standard_child_pipe_handler) Child 24316 () exited with status 0 Is there any change for ldap default configuration in samba4.7.x and samba4.8.x comparing to samba 4.5.x? If so, what should I do tomake it back to normal. Thanks RyanYang