(gdb) bt full
#0  0x00007f5280f26250 in fdatasync () from /lib/x86_64-linux-gnu/libc.so.6
No symbol table info available.
#1  0x00007f527f3013f4 in transaction_sync (tdb=0x7f5285b93760, offset=8212, length=4) at ../lib/tdb/common/transaction.c:554
No locals.
#2  0x00007f527f302127 in transaction_setup_recovery (tdb=0x7f5285b93760, magic_offset=0x7f52872ddc10) at ../lib/tdb/common/transaction.c:914
        recovery_size = 4108
        data = 0x7f52869896d0 "x\027\037\201R\177"
        p = 0x7f528698a6f0 ""
        methods = 0x7f527f509d80
        rec = 0x7f52869896d0
        recovery_offset = 8192
        recovery_max_size = 413672
        old_map_size = 421888
        magic = 4114333927
        tailer = 413696
        i = 2
#3  0x00007f527f30239e in _tdb_transaction_prepare_commit (tdb=0x7f5285b93760) at ../lib/tdb/common/transaction.c:981
        methods = 0x7f527f509d80
#4  0x00007f527f3024e2 in tdb_transaction_prepare_commit (tdb=0x7f5285b93760) at ../lib/tdb/common/transaction.c:1014
No locals.
#5  0x00007f526bb03208 in partition_metadata_prepare_commit (module=0x7f5285a6da10) at ../source4/dsdb/samdb/ldb_modules/partition_metadata.c:408
        data = 0x7f5285a700f0
        tdb = 0x7f5285b93760
#6  0x00007f526bafef3a in partition_prepare_commit (module=0x7f5285a6da10) at ../source4/dsdb/samdb/ldb_modules/partition.c:889
        i = 5
        data = 0x7f5285a700f0
        ret = 0
#7  0x00007f5284d0f9bc in ldb_next_prepare_commit (module=0x7f5285a6da10) at ../lib/ldb/common/ldb_modules.c:628
        ret = 32594
#8  0x00007f526cd35a23 in linked_attributes_prepare_commit (module=0x7f5285a6c600) at ../source4/dsdb/samdb/ldb_modules/linked_attributes.c:1203
        la_private = 0x7f5286563260
        ac = 0x0
        __FUNCTION__ = "linked_attributes_prepare_commit"
#9  0x00007f5284d0f9bc in ldb_next_prepare_commit (module=0x7f5285a6c600) at ../lib/ldb/common/ldb_modules.c:628
        ret = 0
#10 0x00007f526b2db65f in replmd_prepare_commit (module=0x7f5285a6c800) at ../source4/dsdb/samdb/ldb_modules/repl_meta_data.c:5272
        replmd_private = 0x7f5285a6c500
        la = 0x0
        prev = 0x7fff7fbb9390
        bl = 0x0
        ret = 0
#11 0x00007f5284d0f9bc in ldb_next_prepare_commit (module=0x7f5285a6c800) at ../lib/ldb/common/ldb_modules.c:628
        ret = 32594
#12 0x00007f526e16aa98 in descriptor_prepare_commit (module=0x7f5285a6e340) at ../source4/dsdb/samdb/ldb_modules/descriptor.c:1335
        descriptor_private = 0x7f5285a6cf10
        c = 0x0
        n = 0x11
        ret = 0
#13 0x00007f5284d2d0a7 in ldb_transaction_prepare_commit (ldb=0x7f52859e16c0) at ../lib/ldb/common/ldb.c:409
        module = 0x7f5285a6e340
        status = 32594
#14 0x00007f5284d2d216 in ldb_transaction_commit (ldb=0x7f52859e16c0) at ../lib/ldb/common/ldb.c:441
        module = 0x232b
        status = 511
#15 0x00007f5270f05ccf in handle_updates (dns=0x7f52866f1140, mem_ctx=0x7f52862ed140, zone=0x7f52872da230, prereqs=0x7f5286915e00, pcount=1, updates=0x7f5286963500, upd_count=3,
    tkey=0x0) at ../source4/dns_server/dns_update.c:680
        zone_dn = 0x7f528657c260
        werror = {w = 0}
        ret = 0
        ri = 3
        tmp_ctx = 0x7f52864672d0
        __FUNCTION__ = "handle_updates"
---Type <return> to continue, or q <return> to quit---
#16 0x00007f5270f0628a in dns_server_process_update (dns=0x7f52866f1140, state=0x7f52862ed180, mem_ctx=0x7f52862ed140, in=0x7f52862ed150, prereqs=0x7f52862ed1c0,
    prereq_count=0x7f52862ed1ae, updates=0x7f52862ed1c8, update_count=0x7f52862ed1b0, additional=0x7f52862ed1d0, arcount=0x7f52862ed1b2) at ../source4/dns_server/dns_update.c:799
        zone = 0x7f52872da230
        z = 0x7f528657fb00
        host_part_len = 0
        werror = {w = 0}
        tkey = 0x0
        __FUNCTION__ = "dns_server_process_update"
#17 0x00007f5270f00171 in dns_process_send (mem_ctx=0x7f528627f1c0, ev=0x7f52859df110, dns=0x7f52866f1140, in=0x7f528627f1d0) at ../source4/dns_server/dns_server.c:176
        req = 0x7f52866716d0
        subreq = 0x7f528628a180
        state = 0x7f52862ed140
        ndr_err = NDR_ERR_SUCCESS
        ret = {w = 0}
        forwarder = 0x7f52859cd8e0 "205.171.3.65"
        __FUNCTION__ = "dns_process_send"
#18 0x00007f5270f00d68 in dns_udp_call_loop (subreq=0x0) at ../source4/dns_server/dns_server.c:514
        sock = 0x7f5285e2f930
        dns = 0x7f52866f1140
        call = 0x7f528627f1c0
        buf = 0x7f5285b59050 "\372\v("
        len = 110
        sys_errno = 32594
        __FUNCTION__ = "dns_udp_call_loop"
#19 0x00007f52837f38e3 in _tevent_req_notify_callback (req=0x7f528628a1d0, location=0x7f527e588ce1 "../lib/tsocket/tsocket.c:239") at ../lib/tevent/tevent_req.c:101
No locals.
#20 0x00007f52837f3915 in tevent_req_finish (req=0x7f528628a1d0, state=TEVENT_REQ_DONE, location=0x7f527e588ce1 "../lib/tsocket/tsocket.c:239") at ../lib/tevent/tevent_req.c:110
No locals.
#21 0x00007f52837f393c in _tevent_req_done (req=0x7f528628a1d0, location=0x7f527e588ce1 "../lib/tsocket/tsocket.c:239") at ../lib/tevent/tevent_req.c:116
No locals.
#22 0x00007f527e57fb1a in tdgram_recvfrom_done (subreq=0x7f5285c2a950) at ../lib/tsocket/tsocket.c:239
        req = 0x7f528628a1d0
        state = 0x7f52862e2950
        ret = 110
        sys_errno = 32594
#23 0x00007f52837f38e3 in _tevent_req_notify_callback (req=0x7f5285c2a950, location=0x7f527e589ec0 "../lib/tsocket/tsocket_bsd.c:972") at ../lib/tevent/tevent_req.c:101
No locals.
#24 0x00007f52837f3915 in tevent_req_finish (req=0x7f5285c2a950, state=TEVENT_REQ_DONE, location=0x7f527e589ec0 "../lib/tsocket/tsocket_bsd.c:972")
    at ../lib/tevent/tevent_req.c:110
No locals.
#25 0x00007f52837f393c in _tevent_req_done (req=0x7f5285c2a950, location=0x7f527e589ec0 "../lib/tsocket/tsocket_bsd.c:972") at ../lib/tevent/tevent_req.c:116
No locals.
#26 0x00007f527e5830cc in tdgram_bsd_recvfrom_handler (private_data=0x7f5285c2a950) at ../lib/tsocket/tsocket_bsd.c:972
        req = 0x7f5285c2a950
        state = 0x7f52862866b0
        dgram = 0x7f5286d5a640
        bsds = 0x7f5286882f00
        bsda = 0x7f5286709190
        ret = 110
        err = 0
        retry = false
#27 0x00007f527e5827a8 in tdgram_bsd_fde_handler (ev=0x7f52859df110, fde=0x7f52866a08e0, flags=1, private_data=0x7f5286882f00) at ../lib/tsocket/tsocket_bsd.c:701
        bsds = 0x7f5286882f00
#28 0x00007f52837fa512 in epoll_event_loop (epoll_ev=0x7f52859df320, tvalp=0x7fff7fbb9850) at ../lib/tevent/tevent_epoll.c:736
        fde = 0x7f52866a08e0
        flags = 1
        mpx_fde = 0x0
        ret = 1
        i = 0
        events = {{events = 1, data = {ptr = 0x7f52866a08e0, fd = -2039871264, u32 = 2255096032, u64 = 139992419141856}}}
        timeout = 30000
        wait_errno = 0
---Type <return> to continue, or q <return> to quit---
#29 0x00007f52837fab26 in epoll_event_loop_once (ev=0x7f52859df110, location=0x7f5278576890 "../source4/smbd/process_standard.c:186") at ../lib/tevent/tevent_epoll.c:931
        epoll_ev = 0x7f52859df320
        tval = {tv_sec = 30, tv_usec = 0}
        panic_triggered = false
#30 0x00007f52837f78ab in std_event_loop_once (ev=0x7f52859df110, location=0x7f5278576890 "../source4/smbd/process_standard.c:186") at ../lib/tevent/tevent_standard.c:112
        glue_ptr = 0x7f52859df1f0
        glue = 0x7f52859df1f0
        ret = 32594
#31 0x00007f52837f1f5f in _tevent_loop_once (ev=0x7f52859df110, location=0x7f5278576890 "../source4/smbd/process_standard.c:186") at ../lib/tevent/tevent.c:530
        ret = 0
        nesting_stack_ptr = 0x0
#32 0x00007f52837f21bf in tevent_common_loop_wait (ev=0x7f52859df110, location=0x7f5278576890 "../source4/smbd/process_standard.c:186") at ../lib/tevent/tevent.c:634
        ret = 0
#33 0x00007f52837f794d in std_event_loop_wait (ev=0x7f52859df110, location=0x7f5278576890 "../source4/smbd/process_standard.c:186") at ../lib/tevent/tevent_standard.c:138
        glue_ptr = 0x7f52859df1f0
        glue = 0x7f52859df1f0
        ret = 32594
#34 0x00007f52837f228a in _tevent_loop_wait (ev=0x7f52859df110, location=0x7f5278576890 "../source4/smbd/process_standard.c:186") at ../lib/tevent/tevent.c:653
No locals.
#35 0x00007f52785764e7 in standard_new_task (ev=0x7f52859df110, lp_ctx=0x7f52859ca810, service_name=0x7f5270f08edf "dns", new_task=0x7f52840694c6 <task_server_callback>,
    private_data=0x7f52872f80f0) at ../source4/smbd/process_standard.c:186
        pid = 20005
#36 0x00007f5284069668 in task_server_startup (event_ctx=0x7f52859df110, lp_ctx=0x7f52859ca810, service_name=0x7f5270f08edf "dns", model_ops=0x7f5278776d40,
    task_init=0x7f5270f016d0 <dns_task_init>) at ../source4/smbd/service_task.c:112
        state = 0x7f52872f80f0
#37 0x00007f5284067b4a in server_service_init (name=0x7f52859cfcc0 "dns", event_context=0x7f52859df110, lp_ctx=0x7f52859ca810, model_ops=0x7f5278776d40)
    at ../source4/smbd/service.c:63
        srv = 0x7f52859de990
#38 0x00007f5284067c84 in server_service_startup (event_ctx=0x7f52859df110, lp_ctx=0x7f52859ca810, model=0x7f528538fa3a "standard", server_services=0x7f52859cfe50)
    at ../source4/smbd/service.c:95
        status = {v = 0}
        i = 12
        model_ops = 0x7f5278776d40
        __FUNCTION__ = "server_service_startup"
#39 0x00007f528538bc10 in binary_smbd_main (binary_name=0x7f528538f88b "samba", argc=1, argv=0x7fff7fbb9e58) at ../source4/smbd/server.c:477
        opt_daemon = true
        opt_interactive = false
        opt = -1
        pc = 0x7f52859c9040
        static_init = {0x7f52840678fc <server_service_auth_init>, 0x7f528406a423 <server_service_echo_init>, 0}
        shared_init = 0x7f5285a06f50
        event_ctx = 0x7f52859df110
        stdin_event_flags = 0
        status = {v = 0}
        model = 0x7f528538fa3a "standard"
        max_runtime = 0
        long_options = {{longName = 0x0, shortName = 0 '\000', argInfo = 4, arg = 0x7f5281403220, val = 0, descrip = 0x7f528538fa43 "Help options:", argDescrip = 0x0}, {
            longName = 0x7f528538fa51 "daemon", shortName = 68 'D', argInfo = 0, arg = 0x0, val = 1000, descrip = 0x7f528538fa58 "Become a daemon (default)", argDescrip = 0x0}, {
            longName = 0x7f528538fa72 "interactive", shortName = 105 'i', argInfo = 0, arg = 0x0, val = 1001, descrip = 0x7f528538fa80 "Run interactive (not a daemon)",
            argDescrip = 0x0}, {longName = 0x7f528538fa9f "model", shortName = 77 'M', argInfo = 1, arg = 0x0, val = 1002, descrip = 0x7f528538faa5 "Select process model",
            argDescrip = 0x7f528538faba "MODEL"}, {longName = 0x7f528538fac0 "maximum-runtime", shortName = 0 '\000', argInfo = 2, arg = 0x7fff7fbb9d34, val = 0,
            descrip = 0x7f528538fad0 "set maximum runtime of the server process, till autotermination", argDescrip = 0x7f528538fb10 "seconds"}, {
            longName = 0x7f528538fb18 "show-build", shortName = 98 'b', argInfo = 0, arg = 0x0, val = 1003, descrip = 0x7f528538fb23 "show build info", argDescrip = 0x0}, {
            longName = 0x0, shortName = 0 '\000', argInfo = 4, arg = 0x7f52855936e0, val = 0, descrip = 0x7f528538fb33 "Common Samba options:", argDescrip = 0x0}, {
            longName = 0x0, shortName = 0 '\000', argInfo = 4, arg = 0x7f52855938a0, val = 0, descrip = 0x7f528538fb49 "Version options:", argDescrip = 0x0}, {longName = 0x0,
            shortName = 0 '\000', argInfo = 0, arg = 0x0, val = 0, descrip = 0x0, argDescrip = 0x0}}
        __FUNCTION__ = "binary_smbd_main"
#40 0x00007f528538bcdf in main (argc=1, argv=0x7fff7fbb9e58) at ../source4/smbd/server.c:497
No locals.