Если в конфиге агента явно задать параметр ListenIP, до демон валится при запуске с диагностикой:

================================
Apr 21 09:27:38 mars zabbix_agentd: *** glibc has detected an error in /usr/sbin/zabbix_agentd: free(): invalid pointer: 0x000000000042628f ***
Apr 21 09:27:38 mars zabbix_agentd: ======= Backtrace: =========
Apr 21 09:27:38 mars zabbix_agentd: /lib64/libc.so.6(+0x71ad6)[0x7f5f8d3e3ad6]
Apr 21 09:27:38 mars zabbix_agentd: /lib64/libc.so.6(cfree+0x70)[0x7f5f8d3e8980]
Apr 21 09:27:38 mars zabbix_agentd: /usr/sbin/zabbix_agentd[0x41a431]
Apr 21 09:27:38 mars zabbix_agentd: /usr/sbin/zabbix_agentd[0x40b856]
Apr 21 09:27:38 mars zabbix_agentd: /usr/sbin/zabbix_agentd(main+0x116)[0x40c066]
Apr 21 09:27:38 mars zabbix_agentd: /lib64/libc.so.6(__libc_start_main+0xfd)[0x7f5f8d390c5d]
Apr 21 09:27:38 mars zabbix_agentd: /usr/sbin/zabbix_agentd[0x407449]
Apr 21 09:27:38 mars zabbix_agentd: ======= Memory map: ========
Apr 21 09:27:38 mars zabbix_agentd: 00400000-00430000 r-xp 00000000 08:05 271672                             /usr/sbin/zabbix_agentd
Apr 21 09:27:38 mars zabbix_agentd: 0062f000-00630000 r--p 0002f000 08:05 271672                             /usr/sbin/zabbix_agentd
Apr 21 09:27:38 mars zabbix_agentd: 00630000-00631000 rw-p 00030000 08:05 271672                             /usr/sbin/zabbix_agentd
Apr 21 09:27:38 mars zabbix_agentd: 00631000-00658000 rw-p 00000000 00:00 0                                  [heap]
Apr 21 09:27:38 mars zabbix_agentd: 7f5f84000000-7f5f84021000 rw-p 00000000 00:00 0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f84021000-7f5f88000000 ---p 00000000 00:00 0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8b5df000-7f5f8b5f4000 r-xp 00000000 08:01 62                         /lib64/libgcc_s.so.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8b5f4000-7f5f8b7f3000 ---p 00015000 08:01 62                         /lib64/libgcc_s.so.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8b7f3000-7f5f8b7f4000 r--p 00014000 08:01 62                         /lib64/libgcc_s.so.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8b7f4000-7f5f8b7f5000 rw-p 00015000 08:01 62                         /lib64/libgcc_s.so.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8b7f5000-7f5f8b80c000 r-xp 00000000 08:01 48                         /lib64/libpthread-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8b80c000-7f5f8ba0b000 ---p 00017000 08:01 48                         /lib64/libpthread-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8ba0b000-7f5f8ba0c000 r--p 00016000 08:01 48                         /lib64/libpthread-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8ba0c000-7f5f8ba0d000 rw-p 00017000 08:01 48                         /lib64/libpthread-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8ba0d000-7f5f8ba11000 rw-p 00000000 00:00 0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8ba11000-7f5f8ba13000 r-xp 00000000 08:01 185                        /lib64/libkeyutils.so.1.3
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8ba13000-7f5f8bc12000 ---p 00002000 08:01 185                        /lib64/libkeyutils.so.1.3
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8bc12000-7f5f8bc13000 r--p 00001000 08:01 185                        /lib64/libkeyutils.so.1.3
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8bc13000-7f5f8bc14000 rw-p 00002000 08:01 185                        /lib64/libkeyutils.so.1.3
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8bc14000-7f5f8bc1b000 r-xp 00000000 08:01 1101                       /lib64/libkrb5support.so.0.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8bc1b000-7f5f8be1a000 ---p 00007000 08:01 1101                       /lib64/libkrb5support.so.0.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8be1a000-7f5f8be1b000 r--p 00006000 08:01 1101                       /lib64/libkrb5support.so.0.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8be1b000-7f5f8be1c000 rw-p 00007000 08:01 1101                       /lib64/libkrb5support.so.0.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8be1c000-7f5f8be1f000 r-xp 00000000 08:01 133                        /lib64/libcom_err.so.2.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8be1f000-7f5f8c01e000 ---p 00003000 08:01 133                        /lib64/libcom_err.so.2.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c01e000-7f5f8c01f000 r--p 00002000 08:01 133                        /lib64/libcom_err.so.2.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c01f000-7f5f8c020000 rw-p 00003000 08:01 133                        /lib64/libcom_err.so.2.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c020000-7f5f8c038000 r-xp 00000000 08:01 73                         /lib64/libz.so.1.2.5
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c038000-7f5f8c237000 ---p 00018000 08:01 73                         /lib64/libz.so.1.2.5
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c237000-7f5f8c238000 r--p 00017000 08:01 73                         /lib64/libz.so.1.2.5
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c238000-7f5f8c239000 rw-p 00018000 08:01 73                         /lib64/libz.so.1.2.5
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c239000-7f5f8c25e000 r-xp 00000000 08:01 1097                       /lib64/libk5crypto.so.3.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c25e000-7f5f8c45d000 ---p 00025000 08:01 1097                       /lib64/libk5crypto.so.3.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c45d000-7f5f8c45f000 r--p 00024000 08:01 1097                       /lib64/libk5crypto.so.3.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c45f000-7f5f8c460000 rw-p 00026000 08:01 1097                       /lib64/libk5crypto.so.3.1
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c460000-7f5f8c4fc000 r-xp 00000000 08:01 1099                       /lib64/libkrb5.so.3.3
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c4fc000-7f5f8c6fb000 ---p 0009c000 08:01 1099                       /lib64/libkrb5.so.3.3
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c6fb000-7f5f8c6fe000 r--p 0009b000 08:01 1099                       /lib64/libkrb5.so.3.3
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c6fe000-7f5f8c700000 rw-p 0009e000 08:01 1099                       /lib64/libkrb5.so.3.3
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c700000-7f5f8c70c000 r-xp 00000000 08:01 26                         /lib64/libcrypt-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c70c000-7f5f8c90b000 ---p 0000c000 08:01 26                         /lib64/libcrypt-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c90b000-7f5f8c90c000 r--p 0000b000 08:01 26                         /lib64/libcrypt-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c90c000-7f5f8c90d000 rw-p 0000c000 08:01 26                         /lib64/libcrypt-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c90d000-7f5f8c93b000 rw-p 00000000 00:00 0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c93b000-7f5f8c93d000 r-xp 00000000 08:01 153                        /lib64/libdl-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8c93d000-7f5f8cb3d000 ---p 00002000 08:01 153                        /lib64/libdl-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8cb3d000-7f5f8cb3e000 r--p 00002000 08:01 153                        /lib64/libdl-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8cb3e000-7f5f8cb3f000 rw-p 00003000 08:01 153                        /lib64/libdl-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8cb3f000-7f5f8cccd000 r-xp 00000000 08:01 27                         /lib64/libcrypto.so.1.0.0h
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8cccd000-7f5f8cecc000 ---p 0018e000 08:01 27                         /lib64/libcrypto.so.1.0.0h
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8cecc000-7f5f8cee6000 r--p 0018d000 08:01 27                         /lib64/libcrypto.so.1.0.0h
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8cee6000-7f5f8cef0000 rw-p 001a7000 08:01 27                         /lib64/libcrypto.so.1.0.0h
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8cef0000-7f5f8cef4000 rw-p 00000000 00:00 0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8cef4000-7f5f8cf4e000 r-xp 00000000 08:01 148                        /lib64/libssl.so.1.0.0h
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8cf4e000-7f5f8d14d000 ---p 0005a000 08:01 148                        /lib64/libssl.so.1.0.0h
Apr 21 09:27:38 mars zabbix_agentd: 7f
Apr 21 09:27:38 mars zabbix_agentd: 5f8d14d000-7f5f8d150000 r--p 00059000 08:01 148                        /lib64/libssl.so.1.0.0h
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d150000-7f5f8d156000 rw-p 0005c000 08:01 148                        /lib64/libssl.so.1.0.0h
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d156000-7f5f8d171000 r-xp 00000000 08:01 295                        /lib64/libsasl2.so.2.0.24
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d171000-7f5f8d370000 ---p 0001b000 08:01 295                        /lib64/libsasl2.so.2.0.24
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d370000-7f5f8d371000 r--p 0001a000 08:01 295                        /lib64/libsasl2.so.2.0.24
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d371000-7f5f8d372000 rw-p 0001b000 08:01 295                        /lib64/libsasl2.so.2.0.24
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d372000-7f5f8d4d1000 r-xp 00000000 08:01 22                         /lib64/libc-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d4d1000-7f5f8d6d0000 ---p 0015f000 08:01 22                         /lib64/libc-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d6d0000-7f5f8d6d4000 r--p 0015e000 08:01 22                         /lib64/libc-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d6d4000-7f5f8d6d5000 rw-p 00162000 08:01 22                         /lib64/libc-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d6d5000-7f5f8d6da000 rw-p 00000000 00:00 0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d6da000-7f5f8d6ed000 r-xp 00000000 08:01 3598                       /lib64/libresolv-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d6ed000-7f5f8d8ed000 ---p 00013000 08:01 3598                       /lib64/libresolv-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d8ed000-7f5f8d8ee000 r--p 00013000 08:01 3598                       /lib64/libresolv-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d8ee000-7f5f8d8ef000 rw-p 00014000 08:01 3598                       /lib64/libresolv-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d8ef000-7f5f8d8f1000 rw-p 00000000 00:00 0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d8f1000-7f5f8d8ff000 r-xp 00000000 08:01 1105                       /lib64/liblber-2.4.so.2.6.0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8d8ff000-7f5f8dafe000 ---p 0000e000 08:01 1105                       /lib64/liblber-2.4.so.2.6.0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8dafe000-7f5f8daff000 r--p 0000d000 08:01 1105                       /lib64/liblber-2.4.so.2.6.0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8daff000-7f5f8db00000 rw-p 0000e000 08:01 1105                       /lib64/liblber-2.4.so.2.6.0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8db00000-7f5f8db44000 r-xp 00000000 08:01 1107                       /lib64/libldap-2.4.so.2.6.0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8db44000-7f5f8dd43000 ---p 00044000 08:01 1107                       /lib64/libldap-2.4.so.2.6.0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8dd43000-7f5f8dd44000 r--p 00043000 08:01 1107                       /lib64/libldap-2.4.so.2.6.0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8dd44000-7f5f8dd46000 rw-p 00044000 08:01 1107                       /lib64/libldap-2.4.so.2.6.0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8dd46000-7f5f8dd65000 r-xp 00000000 08:01 147                        /lib64/ld-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8df53000-7f5f8df5c000 rw-p 00000000 00:00 0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8df62000-7f5f8df64000 rw-p 00000000 00:00 0
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8df64000-7f5f8df65000 r--p 0001e000 08:01 147                        /lib64/ld-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8df65000-7f5f8df66000 rw-p 0001f000 08:01 147                        /lib64/ld-2.11.3.so
Apr 21 09:27:38 mars zabbix_agentd: 7f5f8df66000-7f5f8df67000 rw-p 00000000 00:00 0
Apr 21 09:27:38 mars zabbix_agentd: 7fff93b13000-7fff93b34000 rw-p 00000000 00:00 0                          [stack]
Apr 21 09:27:38 mars zabbix_agentd: 7fff93b4b000-7fff93b4c000 r-xp 00000000 00:00 0                          [vdso]
Apr 21 09:27:38 mars zabbix_agentd: ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0                  [vsyscall]
Apr 21 09:27:38 mars zabbix_agentd: zabbix_agentd startup failed
========================

Похоже, проблема в src/zabbix_agent/zbxconf.c, а именно в:

char   *CONFIG_LISTEN_IP               = "0.0.0.0";

так как в более новых редакциях там уже стоит:

char   *CONFIG_LISTEN_IP               = NULL;