This is one single consecutive line of events, but there are two stages, first showing working correctly, secong showing crashes after debugging enabled as in Postfix debugging page: Feb 23 08:37:35 gbn kernel: [30113.317303] grsec: shutdown auth success for /sbin/gradm[gradm:14376] uid/euid:0/0 gid/egid:0/0, parent /bin/bash[bash:2886] uid/euid:0/0 gid/egid:0/0 Feb 23 08:37:44 gbn postfix/postfix-script[14386]: refreshing the Postfix mail system Feb 23 08:37:44 gbn postfix/master[3561]: reload -- version 3.0.0, configuration /etc/postfix Feb 23 08:38:17 gbn postfix/qmgr[14395]: 1B824380D48: from=, size=672, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: 366B338195D: from=, size=828, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: A28A63836D1: from=, size=383, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: 8BBBE38313B: from=, size=203664, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: C18CC3836D9: from=, size=1260797, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: DFB9A3815CE: from=, size=203664, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: 910C3380D3E: from=, size=665, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: 9ABE9380D20: from=, size=188702, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: C38B838453D: from=, size=828, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: 1BD94380DE3: from=, size=383, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: CD602383163: from=, size=828, nrcpt=1 (queue active) Feb 23 08:38:17 gbn postfix/qmgr[14395]: B0C643830CD: from=, size=383, nrcpt=1 (queue active) Feb 23 08:38:18 gbn postfix/local[14399]: 1B824380D48: to=, relay=local, delay=10968, delays=10968/0.08/0/0.11, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/qmgr[14395]: 1B824380D48: removed Feb 23 08:38:18 gbn postfix/local[14401]: 366B338195D: to=, orig_to=, relay=local, delay=9249, delays=9249/0.06/0/0.18, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/qmgr[14395]: 366B338195D: removed Feb 23 08:38:18 gbn postfix/local[14399]: A28A63836D1: to=, relay=local, delay=2065, delays=2064/0.16/0/0.14, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/qmgr[14395]: A28A63836D1: removed Feb 23 08:38:18 gbn postfix/local[14401]: 8BBBE38313B: to=, orig_to=, relay=local, delay=5487, delays=5486/0.24/0/0.18, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/qmgr[14395]: 8BBBE38313B: removed Feb 23 08:38:18 gbn postfix/local[14399]: C18CC3836D9: to=, orig_to=, relay=local, delay=1899, delays=1898/0.3/0/0.17, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/qmgr[14395]: C18CC3836D9: removed Feb 23 08:38:18 gbn postfix/local[14401]: DFB9A3815CE: to=, orig_to=, relay=local, delay=9086, delays=9085/0.42/0/0.16, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/qmgr[14395]: DFB9A3815CE: removed Feb 23 08:38:18 gbn postfix/local[14399]: 910C3380D3E: to=, relay=local, delay=12180, delays=12179/0.47/0/0.16, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/qmgr[14395]: 910C3380D3E: removed Feb 23 08:38:18 gbn postfix/local[14401]: C38B838453D: to=, orig_to=, relay=local, delay=2065, delays=2064/0.63/0/0.11, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/local[14402]: 9ABE9380D20: to=, orig_to=, relay=local, delay=19204, delays=19203/0.58/0/0.16, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/qmgr[14395]: C38B838453D: removed Feb 23 08:38:18 gbn postfix/qmgr[14395]: 9ABE9380D20: removed Feb 23 08:38:18 gbn postfix/local[14401]: CD602383163: to=, orig_to=, relay=local, delay=5651, delays=5650/0.74/0/0.1, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/local[14399]: 1BD94380DE3: to=, relay=local, delay=9250, delays=9249/0.74/0/0.1, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/qmgr[14395]: CD602383163: removed Feb 23 08:38:18 gbn postfix/qmgr[14395]: 1BD94380DE3: removed Feb 23 08:38:18 gbn postfix/local[14402]: B0C643830CD: to=, relay=local, delay=5651, delays=5650/0.84/0/0.07, dsn=2.0.0, status=sent (delivered to maildir) Feb 23 08:38:18 gbn postfix/qmgr[14395]: B0C643830CD: removed Feb 23 08:43:51 gbn postfix/postfix-script[14493]: refreshing the Postfix mail system Feb 23 08:43:51 gbn postfix/master[3561]: reload -- version 3.0.0, configuration /etc/postfix Feb 23 08:43:51 gbn postfix/pickup[14499]: running: PATH=/bin:/usr/bin:/usr/local/bin; export PATH; (echo cont;?echo where) | gdb /usr/libexec/postfix/pickup 14499 2>&1?>/etc/postfix/pickup.14499.log & sleep 5 Feb 23 08:43:51 gbn postfix/qmgr[14500]: running: PATH=/bin:/usr/bin:/usr/local/bin; export PATH; (echo cont;?echo where) | gdb /usr/libexec/postfix/qmgr 14500 2>&1?>/etc/postfix/qmgr.14500.log & sleep 5 Feb 23 08:43:51 gbn kernel: [30489.757708] grsec: process /usr/libexec/postfix/pickup(pickup:14499) attached to via ptrace by /usr/bin/gdb[gdb:14507] uid/euid:0/0 gid/egid:0/0, parent /bin/bash[sh:14501] uid/euid:0/0 gid/egid:0/0 Feb 23 08:43:51 gbn kernel: [30489.760510] grsec: process /usr/libexec/postfix/qmgr(qmgr:14500) attached to via ptrace by /usr/bin/gdb[gdb:14505] uid/euid:0/0 gid/egid:0/0, parent /bin/bash[sh:14502] uid/euid:0/0 gid/egid:0/0 Feb 23 08:43:51 gbn kernel: [30489.762784] PAX: execution attempt in: , 3a0d8adf000-3a0d8ae2000 3a0d8adf000 Feb 23 08:43:51 gbn kernel: [30489.762790] PAX: terminating task: /usr/bin/gdb(gdb):14515, uid/euid: 0/0, PC: 000003a0d8adf000, SP: 000003d728edf0c0 Feb 23 08:43:51 gbn kernel: [30489.762793] PAX: bytes at PC: cc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Feb 23 08:43:51 gbn kernel: [30489.762808] PAX: bytes at SP-8: 000003a0d8adf000 0000000000000000 db2cd003f1af9d00 000003d728edf140 0000001965c07500 0000001965c07420 0000001968adb180 000000196559fb80 0000000000000000 000003d728edf190 0000001965549cc1 Feb 23 08:43:51 gbn kernel: [30489.762828] grsec: bruteforce prevention initiated for the next 30 minutes or until service restarted, stalling each fork 30 seconds. Please investigate the crash report for /usr/bin/gdb[gdb:14515] uid/euid:0/0 gid/egid:0/0, parent /usr/bin/gdb[gdb:14507] uid/euid:0/0 gid/egid:0/0 Feb 23 08:43:51 gbn kernel: [30489.762842] grsec: denied resource overstep by requesting 4096 for RLIMIT_CORE against limit 0 for /usr/bin/gdb[gdb:14515] uid/euid:0/0 gid/egid:0/0, parent /usr/bin/gdb[gdb:14507] uid/euid:0/0 gid/egid:0/0 Feb 23 08:43:51 gbn kernel: [30489.763999] PAX: execution attempt in: , 2fb322e7000-2fb322ea000 2fb322e7000 Feb 23 08:43:51 gbn kernel: [30489.764005] PAX: terminating task: /usr/bin/gdb(gdb):14516, uid/euid: 0/0, PC: 000002fb322e7000, SP: 000003c0181a8e90 Feb 23 08:43:51 gbn kernel: [30489.764009] PAX: bytes at PC: cc 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 Feb 23 08:43:51 gbn kernel: [30489.764023] PAX: bytes at SP-8: 000002fb322e7000 0000000000000000 5ce42948a02eed00 000003c0181a8f10 0000001540666500 0000001540666420 000000154467b340 000000153fffeb80 0000000000000000 000003c0181a8f60 000000153ffa8cc1 Feb 23 08:43:51 gbn kernel: [30489.764042] grsec: bruteforce prevention initiated for the next 30 minutes or until service restarted, stalling each fork 30 seconds. Please investigate the crash report for /usr/bin/gdb[gdb:14516] uid/euid:0/0 gid/egid:0/0, parent /usr/bin/gdb[gdb:14505] uid/euid:0/0 gid/egid:0/0 Feb 23 08:43:51 gbn kernel: [30489.764056] grsec: denied resource overstep by requesting 4096 for RLIMIT_CORE against limit 0 for /usr/bin/gdb[gdb:14516] uid/euid:0/0 gid/egid:0/0, parent /usr/bin/gdb[gdb:14505] uid/euid:0/0 gid/egid:0/0