Hi again!

I managed to do a full DIT sync with my configuration, but I noticed two things that seem odd to me:

1. When a delta-syncrepl is aborted by stopping slapd after the MDB map was too small for the changelog, after extending the changelog size and restarting slapd, it considered the DIT to be current. So I deleted the chalngelog and the MDB files, and then DIT was synced correctly.
2. I had an incomplete sync, but didn’t notice, so I changed one entry in the DIT. After noticing the mistake, I loaded an older (but complete) LDIF on the other node. However the updated node considered the other node to be more current and started to delete the entries that had just been added again. Is that the way it should work? I doubt it.

And as a matter of fact, after having synced the second node successfully, slapd crashed after some delay when there was no requests (except syncrepl) being processed.

Logs like this:

Node 5 (actively managed):

Apr 24 14:11:07 v05 slapd[15418]: do_syncrep1: rid=106 starting refresh (sending cookie=rid=106,sid=005,csn=20130719093756.074776Z#000000#000#000000;20250217105250.345944Z#000000#001#000000;20250218171739.629994Z#000000#002#000000;20250217065706.238392Z#000000#003#000000;20250227092327.859231Z#000000#005#000000;20250424114618.458377Z#000000#006#000000)

Apr 24 14:11:08 v05 slapd[15418]: do_syncrepl: rid=106 rc -1 retrying (3 retries left)

Node 6 (being synced):

Apr 24 14:08:57 v06 slapd[9902]: accesslog_response: adding a new csn=20250424114618.458377Z#000000#006#000000 into minCSN

Apr 24 14:08:57 v06 slapd[9902]: slap_graduate_commit_csn: removing 0x7fd22079a930 20250424114618.458377Z#000000#006#000000

Apr 24 14:08:57 v06 slapd[9902]: do_syncrep2: rid=105 LDAP_RES_INTERMEDIATE - SYNC_ID_SET

Apr 24 14:08:57 v06 slapd[9902]: do_syncrep2: rid=105 LDAP_RES_INTERMEDIATE - REFRESH_PRESENT

Apr 24 14:11:07 v06 slapd[9902]: conn=1004 op=2 syncprov_op_search: got a persistent search with a cookie=rid=106,sid=005,csn=20130719093756.074776Z#000000#000#000000;20250217105250.345944Z#000000#001#000000;20250218171739.629994Z#000000#002#000000;20250217065706.238392Z#000000#003#000000;20250227092327.859231Z#000000#005#000000;20250424114618.458377Z#000000#006#000000

Apr 24 14:11:07 v06 slapd[9902]: conn=1004 op=2 syncprov_findbase: searching

Apr 24 14:11:07 v06 slapd[9902]: conn=1004 op=2 syncprov_op_search: registered persistent search

Apr 24 14:11:07 v06 systemd[1]: Started Process Core Dump (PID 9920/UID 0).

Apr 24 14:11:08 v06 systemd-coredump[9921]: [🡕] Process 9902 (slapd) of user 76 dumped core.

                                                 Stack trace of thread 9908:

                                                 #0  0x00007fd2476a8dfc __pthread_kill_implementation (libc.so.6 + 0xa8dfc)

                                                 #1  0x00007fd247657842 raise (libc.so.6 + 0x57842)

                                                 #2  0x00007fd24763f5cf abort (libc.so.6 + 0x3f5cf)

                                                 #3  0x00007fd24763f4e7 __assert_fail_base.cold (libc.so.6 + 0x3f4e7)

                                                 #4  0x00007fd24764fb32 __assert_fail (libc.so.6 + 0x4fb32)

                                                 #5  0x00007fd246a25218 n/a (syncprov.so + 0xc218)

                                                #6  0x000055e3e0f504f3 overlay_op_walk (slapd + 0xb74f3)

                                                 #7  0x000055e3e0f506be n/a (slapd + 0xb76be)

#8  0x000055e3e0edee54 fe_op_search (slapd + 0x45e54)

                                                 #9  0x000055e3e0ede726 do_search (slapd + 0x45726)

                                                 #10 0x000055e3e0edc18f n/a (slapd + 0x4318f)

                                                 #11 0x000055e3e0edc98d n/a (slapd + 0x4398d)

                                                 #12 0x00007fd24791cda0 n/a (libldap-2.5.releng.so.0 + 0x48da0)

#13 0x00007fd2476a6f6c start_thread (libc.so.6 + 0xa6f6c)

#14 0x00007fd24772e338 __clone3 (libc.so.6 + 0x12e338)

Stack trace of thread 9902:

                                                 #0  0x00007fd2476a3c1e __futex_abstimed_wait_common (libc.so.6 + 0xa3c1e)

                                                 #1  0x00007fd2476a8b83 __pthread_clockjoin_ex (libc.so.6 + 0xa8b83)

#2  0x000055e3e0ed91ca slapd_daemon (slapd + 0x401ca)

                                                 #3  0x000055e3e0ebc88e main (slapd + 0x2388e)

#4  0x00007fd247640e6c __libc_start_call_main (libc.so.6 + 0x40e6c)

                                                 #5  0x00007fd247640f35 __libc_start_main@@GLIBC_2.34 (libc.so.6 + 0x40f35)

                                                 #6  0x000055e3e0ebc90a _start (slapd + 0x2390a)

                                                 Stack trace of thread 9906:

                                                 #0  0x00007fd2476a3c1e __futex_abstimed_wait_common (libc.so.6 + 0xa3c1e)

                                                 #1  0x00007fd2476a6548 pthread_cond_wait@@GLIBC_2.3.2 (libc.so.6 + 0xa6548)

                                                 #2  0x00007fd24791ce40 n/a (libldap-2.5.releng.so.0 + 0x48e40)

                                                 #3  0x00007fd2476a6f6c start_thread (libc.so.6 + 0xa6f6c)

#4  0x00007fd24772e338 __clone3 (libc.so.6 + 0x12e338)

Stack trace of thread 9907:

                                                 #0  0x00007fd2476a3c1e __futex_abstimed_wait_common (libc.so.6 + 0xa3c1e)

                                                 #1  0x00007fd2476a6548 pthread_cond_wait@@GLIBC_2.3.2 (libc.so.6 + 0xa6548)

                                                 #2  0x00007fd24791ce40 n/a (libldap-2.5.releng.so.0 + 0x48e40)

                                                 #3  0x00007fd2476a6f6c start_thread (libc.so.6 + 0xa6f6c)

#4  0x00007fd24772e338 __clone3 (libc.so.6 + 0x12e338)

Stack trace of thread 9909:

                                                 #0  0x00007fd2476a3c1e __futex_abstimed_wait_common (libc.so.6 + 0xa3c1e)

                                                 #1  0x00007fd2476a6548 pthread_cond_wait@@GLIBC_2.3.2 (libc.so.6 + 0xa6548)

                                                 #2  0x00007fd24791ce40 n/a (libldap-2.5.releng.so.0 + 0x48e40)

                                                 #3  0x00007fd2476a6f6c start_thread (libc.so.6 + 0xa6f6c)

#4  0x00007fd24772e338 __clone3 (libc.so.6 + 0x12e338)

Stack trace of thread 9910:

                                                 #0  0x00007fd2476a3c1e __futex_abstimed_wait_common (libc.so.6 + 0xa3c1e)

                                                 #1  0x00007fd2476a6548 pthread_cond_wait@@GLIBC_2.3.2 (libc.so.6 + 0xa6548)

                                                 #2  0x00007fd24791ce40 n/a (libldap-2.5.releng.so.0 + 0x48e40)

                                                 #3  0x00007fd2476a6f6c start_thread (libc.so.6 + 0xa6f6c)

#4  0x00007fd24772e338 __clone3 (libc.so.6 + 0x12e338)

Stack trace of thread 9911:

                                                 #0  0x00007fd2476a3c1e __futex_abstimed_wait_common (libc.so.6 + 0xa3c1e)

                                                 #1  0x00007fd2476a6548 pthread_cond_wait@@GLIBC_2.3.2 (libc.so.6 + 0xa6548)

                                                 #2  0x00007fd24791ce40 n/a (libldap-2.5.releng.so.0 + 0x48e40)

                                                 #3  0x00007fd2476a6f6c start_thread (libc.so.6 + 0xa6f6c)

#4  0x00007fd24772e338 __clone3 (libc.so.6 + 0x12e338)

Stack trace of thread 9912:

                                                 #0  0x00007fd2476a3c1e __futex_abstimed_wait_common (libc.so.6 + 0xa3c1e)

                                                 #1  0x00007fd2476a6548 pthread_cond_wait@@GLIBC_2.3.2 (libc.so.6 + 0xa6548)

                                                 #2  0x00007fd24791ce40 n/a (libldap-2.5.releng.so.0 + 0x48e40)

                                                 #3  0x00007fd2476a6f6c start_thread (libc.so.6 + 0xa6f6c)

#4  0x00007fd24772e338 __clone3 (libc.so.6 + 0x12e338)

Stack trace of thread 9904:

                                                 #0  0x00007fd24772e796 epoll_wait (libc.so.6 + 0x12e796)

                                                 #1  0x000055e3e0ed607b n/a (slapd + 0x3d07b)

                                                 #2  0x00007fd2476a6f6c start_thread (libc.so.6 + 0xa6f6c)

#3  0x00007fd24772e338 __clone3 (libc.so.6 + 0x12e338)

ELF object binary architecture: AMD x86-64

Apr 24 14:11:08 v06 systemd[1]: systemd-coredump@1-9920-0.service: Deactivated successfully.

Apr 24 14:11:08 v06 systemd[1]: slapd.service: Main process exited, code=dumped, status=6/ABRT

Apr 24 14:11:08 v06 systemd[1]: slapd.service: Failed with result 'core-dump'.

Apr 24 14:11:08 v06 systemd[1]: slapd.service: Consumed 1min 43.162s CPU time.

Rid=106 is cn=config from node 6, BTW.

Kind regards,

Ulrich Windl

From: Windl, Ulrich <u.windl@ukr.de>
Sent: Thursday, April 24, 2025 11:44 AM
To: openldap-technical@openldap.org
Subject: [EXT] RE: core dump when using olcSpSessionlogSource

Update: When I removed the accesslog databases, the problem went away.

Still someone should have a look, I think.

Kind regards,

Ulrich Windl

From: Windl, Ulrich <u.windl@ukr.de>
Sent: Thursday, April 24, 2025 11:39 AM
To: openldap-technical@openldap.org
Subject: [EXT] core dump when using olcSpSessionlogSource

Hi!

Configuring delta-syncrepl, I tried olcSpSessionlogSource instead of olcSPSessionlog.

After slapd war started, it dumped core like this:

…

Apr 24 11:25:41 v05 slapd[5030]: syncprov_db_open: starting syncprov for suffix cn=config

Apr 24 11:25:41 v05 slapd[5030]: conn=-1 op=0 syncprov_findcsn: mode=FIND_MAXCSN csn=

Apr 24 11:25:41 v05 slapd[5030]: syncprov_db_open: starting syncprov for suffix dc=sap,dc=klinik,dc=uni-regensburg,dc=de

Apr 24 11:25:41 v05 slapd[5030]: slapd starting

Apr 24 11:25:41 v05 start[5017]: Starting ldap-server

Apr 24 11:25:41 v05 systemd[1]: Started OpenLDAP Server Daemon.

Apr 24 11:25:41 v05 slapd[5030]: slap_get_csn: conn=1000 op=1 generated new csn=20250424092541.888430Z#000000#005#000000 manage=1

Apr 24 11:25:41 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a01217d0 20250424092541.888430Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd1a01217d0 20250424092541.888430Z#000000#005#000000

Apr 24 11:25:41 v05 ldapmodify[5035]: DIGEST-MD5 common mech free

Apr 24 11:25:41 v05 slapd[5030]: slap_get_csn: conn=1001 op=1 generated new csn=20250424092541.896113Z#000000#005#000000 manage=1

Apr 24 11:25:41 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a0122df0 20250424092541.896113Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: conn=1001 op=1 syncprov_checkpoint: running checkpoint

Apr 24 11:25:41 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd1a0122df0 20250424092541.896113Z#000000#005#000000

Apr 24 11:25:41 v05 ldapmodify[5037]: DIGEST-MD5 common mech free

Apr 24 11:25:41 v05 slapd[5030]: slap_get_csn: conn=1002 op=1 generated new csn=20250424092541.900818Z#000000#005#000000 manage=1

Apr 24 11:25:41 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a0128240 20250424092541.900818Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a012b820 20250424092541.900818Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd1a012b820 20250424092541.900818Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd1a0128240 20250424092541.900818Z#000000#005#000000

Apr 24 11:25:41 v05 ldapmodify[5039]: DIGEST-MD5 common mech free

Apr 24 11:25:41 v05 slapd[5030]: slap_get_csn: conn=1003 op=1 generated new csn=20250424092541.920778Z#000000#005#000000 manage=1

Apr 24 11:25:41 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd19c106d00 20250424092541.920778Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd19c107760 20250424092541.920778Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd19c107760 20250424092541.920778Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd19c106d00 20250424092541.920778Z#000000#005#000000

Apr 24 11:25:41 v05 ldapmodify[5041]: DIGEST-MD5 common mech free

Apr 24 11:25:41 v05 slapd[5030]: slap_get_csn: conn=1004 op=1 generated new csn=20250424092541.937140Z#000000#005#000000 manage=1

Apr 24 11:25:41 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd19c10c9f0 20250424092541.937140Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd19c11c110 20250424092541.937140Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd19c11c110 20250424092541.937140Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd19c10c9f0 20250424092541.937140Z#000000#005#000000

Apr 24 11:25:41 v05 ldapmodify[5043]: DIGEST-MD5 common mech free

Apr 24 11:25:41 v05 slapd[5030]: slap_get_csn: conn=1005 op=1 generated new csn=20250424092541.989098Z#000000#005#000000 manage=1

Apr 24 11:25:41 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a012b920 20250424092541.989098Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a0107320 20250424092541.989098Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd1a0107320 20250424092541.989098Z#000000#005#000000

Apr 24 11:25:41 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd1a012b920 20250424092541.989098Z#000000#005#000000

Apr 24 11:25:41 v05 ldapmodify[5044]: DIGEST-MD5 common mech free

Apr 24 11:25:42 v05 slapd[5030]: slap_get_csn: conn=1006 op=1 generated new csn=20250424092542.004124Z#000000#005#000000 manage=1

Apr 24 11:25:42 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a01277f0 20250424092542.004124Z#000000#005#000000

Apr 24 11:25:42 v05 slapd[5030]: index objectClass 0x0004

Apr 24 11:25:42 v05 slapd[5030]: index entryCSN 0x0004

Apr 24 11:25:42 v05 slapd[5030]: index reqEnd 0x0004

Apr 24 11:25:42 v05 slapd[5030]: index reqResult 0x0004

Apr 24 11:25:42 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a02376f0 20250424092542.004124Z#000000#005#000000

Apr 24 11:25:42 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd1a02376f0 20250424092542.004124Z#000000#005#000000

Apr 24 11:25:42 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd1a01277f0 20250424092542.004124Z#000000#005#000000

Apr 24 11:25:42 v05 ldapmodify[5046]: DIGEST-MD5 common mech free

Apr 24 11:25:42 v05 slapd[5030]: slap_get_csn: conn=1007 op=1 generated new csn=20250424092542.020297Z#000000#005#000000 manage=1

Apr 24 11:25:42 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a010a230 20250424092542.020297Z#000000#005#000000

Apr 24 11:25:42 v05 slapd[5030]: index objectClass 0x0004

Apr 24 11:25:42 v05 slapd[5030]: index entryCSN 0x0004

Apr 24 11:25:42 v05 slapd[5030]: index reqEnd 0x0004

Apr 24 11:25:42 v05 slapd[5030]: index reqResult 0x0004

Apr 24 11:25:42 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a0117770 20250424092542.020297Z#000000#005#000000

Apr 24 11:25:42 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd1a0117770 20250424092542.020297Z#000000#005#000000

Apr 24 11:25:42 v05 slapd[5030]: slap_graduate_commit_csn: removing 0x7fd1a010a230 20250424092542.020297Z#000000#005#000000

Apr 24 11:25:42 v05 ldapmodify[5048]: DIGEST-MD5 common mech free

Apr 24 11:25:42 v05 slapd[5030]: slap_get_csn: conn=1008 op=1 generated new csn=20250424092542.036954Z#000000#005#000000 manage=1

Apr 24 11:25:42 v05 slapd[5030]: slap_queue_csn: queueing 0x7fd1a0237570 20250424092542.036954Z#000000#005#000000

Apr 24 11:25:42 v05 slapd[5030]: syncprov_db_open: starting syncprov for suffix cn=changelog-0

Apr 24 11:25:42 v05 slapd[5030]: [71B blob data]

Apr 24 11:25:42 v05 slapd[5030]: olcSpSessionlogSource: value #0: <olcSpSessionlogSource> failed startup (cn=changelog-0)!

Apr 24 11:25:42 v05 systemd[1]: Started Process Core Dump (PID 5051/UID 0).

Apr 24 11:25:42 v05 systemd-coredump[5052]: [🡕] Process 5030 (slapd) of user 1000 dumped core.

                                                 Stack trace of thread 5034:

                                                 #0  0x00007fd1b82a8dfc __pthread_kill_implementation (libc.so.6 + 0xa8dfc)

                                                 #1  0x00007fd1b8257842 raise (libc.so.6 + 0x57842)

                                                 #2  0x00007fd1b823f5cf abort (libc.so.6 + 0x3f5cf)

                                                 #3  0x00007fd1b8240497 __libc_message.cold (libc.so.6 + 0x40497)

                                                 #4  0x00007fd1b82b34b7 malloc_printerr (libc.so.6 + 0xb34b7)

                                                 #5  0x00007fd1b82b5a69 _int_free (libc.so.6 + 0xb5a69)

                                                 #6  0x00007fd1b82b81df free (libc.so.6 + 0xb81df)

                                                 #7  0x00007fd1b8159bee n/a (syncprov.so + 0x3bee)

                                                 #8  0x000056122f1a02ee overlay_destroy_one (slapd + 0xb82ee)

                                                 #9  0x000056122f1156bd n/a (slapd + 0x2d6bd)

                                                 #10 0x000056122f115fb0 n/a (slapd + 0x2dfb0)

                                                 #11 0x000056122f19f533 overlay_op_walk (slapd + 0xb7533)

                                                 #12 0x000056122f19f6be n/a (slapd + 0xb76be)

                                                 #13 0x000056122f1319ad fe_op_add (slapd + 0x499ad)

                                                 #14 0x000056122f1328d9 do_add (slapd + 0x4a8d9)

                                                 #15 0x000056122f12b18f n/a (slapd + 0x4318f)

                                                 #16 0x000056122f12b98d n/a (slapd + 0x4398d)

                                                 #17 0x00007fd1b86bcda0 n/a (libldap-2.5.releng.so.0 + 0x48da0)

                                                 #18 0x00007fd1b82a6f6c start_thread (libc.so.6 + 0xa6f6c)

#19 0x00007fd1b832e338 __clone3 (libc.so.6 + 0x12e338)

Stack trace of thread 5030:

                                                 #0  0x00007fd1b82a3c1e __futex_abstimed_wait_common (libc.so.6 + 0xa3c1e)

                                                 #1  0x00007fd1b82a8b83 __pthread_clockjoin_ex (libc.so.6 + 0xa8b83)

                                                 #2  0x000056122f1281ca slapd_daemon (slapd + 0x401ca)

                                                 #3  0x000056122f10b88e main (slapd + 0x2388e)

                                                 #4  0x00007fd1b8240e6c __libc_start_call_main (libc.so.6 + 0x40e6c)

                                                 #5  0x00007fd1b8240f35 __libc_start_main@@GLIBC_2.34 (libc.so.6 + 0x40f35)

                                                 #6  0x000056122f10b90a _start (slapd + 0x2390a)

                                                 Stack trace of thread 5038:

                                                 #0  0x00007fd1b82a3c1e __futex_abstimed_wait_common (libc.so.6 + 0xa3c1e)

                                                 #1  0x00007fd1b82a6548 pthread_cond_wait@@GLIBC_2.3.2 (libc.so.6 + 0xa6548)

                                                 #2  0x00007fd1b86bce40 n/a (libldap-2.5.releng.so.0 + 0x48e40)

                                                 #3  0x00007fd1b82a6f6c start_thread (libc.so.6 + 0xa6f6c)

#4  0x00007fd1b832e338 __clone3 (libc.so.6 + 0x12e338)

Stack trace of thread 5032:

                                                 #0  0x00007fd1b832e796 epoll_wait (libc.so.6 + 0x12e796)

                                                 #1  0x000056122f12507b n/a (slapd + 0x3d07b)

                                                 #2  0x00007fd1b82a6f6c start_thread (libc.so.6 + 0xa6f6c)

#3  0x00007fd1b832e338 __clone3 (libc.so.6 + 0x12e338)

ELF object binary architecture: AMD x86-64

Apr 24 11:25:42 v05 ldapmodify[5050]: DIGEST-MD5 common mech free

Apr 24 11:25:42 v05 systemd[1]: slapd.service: Main process exited, code=dumped, status=6/ABRT

Apr 24 11:25:42 v05 systemd[1]: slapd.service: Failed with result 'core-dump'.

Apr 24 11:25:42 v05 systemd[1]: systemd-coredump@1-5051-0.service: Deactivated successfully.

Looks a bit like a bad free() to me.

I was adding the syncprov overlay with the accesslog DB being defined, but the accesslog overlay to set “olcAccessLogDB: cn=changelog-0” wasn’t done yet. The changelog-0 database may have contained outdated entries.

Kind regards,

Ulrich Windl