It is configured with this guide. https://www.howtoforge.com/perfect-server-debian-wheezy-nginx-bind-dovecot-ispconfig-3-p3 Bind9 stopped working, But still active. In one of my servers stopped working bind9 5 days ago I installed CSF firewall due to a stranger was doing DDOS of 880K to my servers already from 3 weeks ago. The rest is still working well. I found important points vi /var/log/syslog Code: SV1 Dec 18 14:16:14 named [2309]: no longer listening on :: # 53 SV1 Dec 18 14:16:14 named [2309]: no longer listening on 127.0.0.1 # 53 SV1 Dec 18 14:16:14 named [2309]: no longer listening on 127.0.0.2 # 53 SV1 Dec 18 14:16:14 named [2309]: no longer listening on 23.XX.1X.136 # 53 ... Dec 18 14:17:29 sv1 postfix/qmgr[4786]: C1E3D162FDB: from=<[email protected]>, size=651, nrcpt=1 (queue active) Dec 18 14:17:38 sv1 kernel: [10101669.517236] Firewall: *TCP_IN Blocked* IN=venet0 OUT= MAC= SRC=107.178.160.194 DST=23.XX.1X.136 LEN=40 TOS Dec 19 02:43:20 sv1 postfix/error[5288]: AB5BB160773: to=<[email protected]>, relay=none, delay=3002, delays=2994/8.1/0/0, dsn=4.4.3, status=deferred (delivery temporarily suspended: Host or domain name not found. Name service error for name=msv1.domain.com type=MX: Host not found, try again) (I always used msv1.domain.com without problems. If used sv1.domain.com the emails do not reach.) Config Nameserver primary, secondary, and together. vi /etc/bind/named.conf.local Code: zone "sv1.domain.com" { type master; allow-transfer {none;}; file "/etc/bind/pri.sv1.domain.com"; }; zone "sv2.domain.com" { type master; allow-transfer {none;}; file "/etc/bind/pri.sv2.domain.com"; }; zone "domain.com" { type master; allow-transfer {none;}; file "/etc/bind/pri.domain.com"; }; You have 5 months this configuration. vi /etc/bind/pri.domain.com Code: $TTL 3600 @ IN SOA sv1.domain.com. admin.domain.com. ( 2015031703 ; serial, todays date + todays serial # 7200 ; refresh, seconds 540 ; retry, seconds 604800 ; expire, seconds 86400 ) ; minimum, seconds ; domain.com. 3600 A 23.XX.1X.136 mail 3600 A 23.XX.1X.136 sv1 86400 A 23.XX.1X.136 sv2 86400 A 23.XX.1X.136 www 3600 A 23.XX.1x.136 domain.com. 3600 MX 10 mail.domain.com. domain.com. 3600 NS sv1.domain.com. domain.com. 3600 NS sv2.domain.com.
Code: root@sv1:~# service bind9 stop [....] Stopping domain name service...: bind9waiting for pid 7947 to die . ok root@sv1:~# ps -ef|grep bind root 21577 21500 0 10:22 pts/0 00:00:00 grep bind
I think that the problem is in the Iptables as I've configured CSF firewall I think that I've blocked me something related to the DNS. root@sv1:~# iptables -L -n -v Code: Chain LOGDROPIN (1 references) pkts bytes target prot opt in out source destination 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:67 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:67 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:68 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:68 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:111 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:111 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:113 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:113 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpts:135:139 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpts:135:139 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:445 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:445 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:500 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:500 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:513 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:513 0 0 DROP tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcp dpt:520 0 0 DROP udp -- * * 0.0.0.0/0 0.0.0.0/0 udp dpt:520 0 0 LOG tcp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix "Firewall: *TCP_IN Blocked* " 3 87 LOG udp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix "Firewall: *UDP_IN Blocked* " 0 0 LOG icmp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix "Firewall: *ICMP_IN Blocked* " 3 87 DROP all -- * * 0.0.0.0/0 0.0.0.0/0 Chain LOGDROPOUT (7 references) pkts bytes target prot opt in out source destination 0 0 LOG tcp -- * * 0.0.0.0/0 0.0.0.0/0 tcpflags: 0x17/0x02 limit: avg 30/min burst 5 LOG flags 8 level 4 prefix "Firewall: *TCP_OUT Blocked* " 0 0 LOG udp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 8 level 4 prefix "Firewall: *UDP_OUT Blocked* " 0 0 LOG icmp -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 8 level 4 prefix "Firewall: *ICMP_OUT Blocked* " 0 0 DROP all -- * * 0.0.0.0/0 0.0.0.0/0 Chain PORTFLOOD (1 references) pkts bytes target prot opt in out source destination 0 0 LOG all -- * * 0.0.0.0/0 0.0.0.0/0 limit: avg 30/min burst 5 LOG flags 0 level 4 prefix "Firewall: *Port Flood* " 0 0 DROP all -- * * 0.0.0.0/0 0.0.0.0/0 23.XX.1x.136 is my real IP. root@sv1:~# cat /var/log/messages Code: Dec 21 09:31:40 sv1 kernel: imklog 5.8.11, log source = /proc/kmsg started. Dec 21 09:31:40 sv1 rsyslogd: [origin software="rsyslogd" swVersion="5.8.11" x-pid="2315" x-info="http://www.rsyslog.com"] start Dec 21 09:32:10 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 4805 due to rate-limiting Dec 21 09:32:16 sv1 rsyslogd-2177: imuxsock lost 137 messages from pid 4805 due to rate-limiting Dec 21 09:33:41 sv1 kernel: [10343626.654939] Firewall: *UDP_IN Blocked* IN=venet0 OUT= MAC= SRC=123.128.43.87 DST=23.XX.1X.136 LEN=29 TOS=0x00 PREC=0x00 TTL=51 ID=59256 DF PROTO=UDP SPT=32297 DPT=53413 LEN=9 Dec 21 09:33:43 sv1 kernel: [10343628.878315] Firewall: *UDP_IN Blocked* IN=venet0 OUT= MAC= SRC=123.128.43.87 DST=23.XX.1X.136 LEN=29 TOS=0x00 PREC=0x00 TTL=51 ID=59257 DF PROTO=UDP SPT=32297 DPT=53413 LEN=9 Dec 21 09:33:46 sv1 kernel: [10343631.860006] Firewall: *UDP_IN Blocked* IN=venet0 OUT= MAC= SRC=123.128.43.87 DST=23.XX.1X.136 LEN=29 TOS=0x00 PREC=0x00 TTL=51 ID=59258 DF PROTO=UDP SPT=32297 DPT=53413 LEN=9 Dec 21 09:35:01 sv1 pure-ftpd: (?@::1) [INFO] New connection from ::1 Dec 21 09:35:01 sv1 pure-ftpd: (?@::1) [INFO] Logout. Dec 21 09:37:10 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 4805 due to rate-limiting Dec 21 09:38:05 sv1 kernel: [10343890.819829] Firewall: *UDP_IN Blocked* IN=venet0 OUT= MAC= SRC=182.68.8.141 DST=23.XX.1X.136 LEN=88 TOS=0x00 PREC=0x00 TTL=240 ID=41494 DF PROTO=UDP SPT=10003 DPT=14660 LEN=68 Dec 21 09:38:11 sv1 rsyslogd-2177: imuxsock lost 323 messages from pid 4805 due to rate-limiting Dec 21 09:38:31 sv1 kernel: [10343916.602086] Firewall: *UDP_IN Blocked* IN=venet0 OUT= MAC= SRC=101.23.65.92 DST=23.XX.1X.136 LEN=29 TOS=0x00 PREC=0x00 TTL=50 ID=55562 DF PROTO=UDP SPT=31583 DPT=53413 LEN=9 Dec 21 09:38:34 sv1 kernel: [10343919.838697] Firewall: *UDP_IN Blocked* IN=venet0 OUT= MAC= SRC=101.23.65.92 DST=23.XX.1X.136 LEN=29 TOS=0x00 PREC=0x00 TTL=50 ID=55563 DF PROTO=UDP SPT=31583 DPT=53413 LEN=9 Dec 21 09:40:01 sv1 pure-ftpd: (?@::1) [INFO] New connection from ::1 Dec 21 09:40:01 sv1 pure-ftpd: (?@::1) [INFO] Logout. Dec 21 09:42:10 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 4805 due to rate-limiting Dec 21 09:43:11 sv1 rsyslogd-2177: imuxsock lost 246 messages from pid 4805 due to rate-limiting Dec 21 09:45:02 sv1 pure-ftpd: (?@::1) [INFO] New connection from ::1 Dec 21 09:45:02 sv1 pure-ftpd: (?@::1) [INFO] Logout. Dec 21 09:47:10 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 4805 due to rate-limiting Dec 21 09:49:11 sv1 rsyslogd-2177: imuxsock lost 659 messages from pid 4805 due to rate-limiting Dec 21 09:50:01 sv1 pure-ftpd: (?@::1) [INFO] New connection from ::1 Dec 21 09:50:01 sv1 pure-ftpd: (?@::1) [INFO] Logout. Dec 21 09:52:05 sv1 kernel: [10344730.122499] Firewall: *TCP_IN Blocked* IN=venet0 OUT= MAC= SRC=51.254.151.5 DST=23.XX.1X.136 LEN=40 TOS=0x00 PREC=0x00 TTL=241 ID=22904 PROTO=TCP SPT=49120 DPT=8080 WINDOW=1024 RES=0x00 SYN URGP=0 Dec 21 09:52:10 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 4805 due to rate-limiting This is my entire iptables Can you see something that blocks the DNS? https://mega.nz/#!xs8DTRAL!x3HNbBl2XMNO0HNY6Js4IwfYYX2zGeIniuRkAXMbA0I
I have been researching deeply and it is a DDOS attack It destroys the DNS Code: Dec 21 05:00:11 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 05:00:13 sv1 rsyslogd-2177: imuxsock lost 113 messages from pid 3485 due to rate-limiting Dec 21 05:00:17 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 05:01:07 sv1 rsyslogd-2177: imuxsock lost 29 messages from pid 3485 due to rate-limiting Dec 21 06:00:12 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 06:00:14 sv1 rsyslogd-2177: imuxsock lost 88 messages from pid 3485 due to rate-limiting Dec 21 06:00:17 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 06:01:08 sv1 rsyslogd-2177: imuxsock lost 109 messages from pid 3485 due to rate-limiting Dec 21 07:00:14 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 07:00:15 sv1 rsyslogd-2177: imuxsock lost 23 messages from pid 3485 due to rate-limiting Dec 21 07:00:20 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 07:00:21 sv1 rsyslogd-2177: imuxsock lost 14 messages from pid 3485 due to rate-limiting Dec 21 07:00:24 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 07:01:09 sv1 rsyslogd-2177: imuxsock lost 31 messages from pid 3485 due to rate-limiting Dec 21 08:00:14 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 08:00:15 sv1 rsyslogd-2177: imuxsock lost 31 messages from pid 3485 due to rate-limiting Dec 21 08:00:18 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 08:00:21 sv1 rsyslogd-2177: imuxsock lost 69 messages from pid 3485 due to rate-limiting Dec 21 09:00:26 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 09:00:29 sv1 rsyslogd-2177: imuxsock lost 136 messages from pid 3485 due to rate-limiting Dec 21 09:32:26 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 09:32:28 sv1 rsyslogd-2177: imuxsock lost 66 messages from pid 3485 due to rate-limiting Dec 21 10:32:33 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 10:32:34 sv1 rsyslogd-2177: imuxsock lost 33 messages from pid 3485 due to rate-limiting Dec 21 10:48:16 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 10:49:12 sv1 rsyslogd-2177: imuxsock lost 12 messages from pid 3485 due to rate-limiting Dec 21 11:32:18 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 11:32:19 sv1 rsyslogd-2177: imuxsock lost 5 messages from pid 3485 due to rate-limiting Dec 21 12:32:19 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 12:32:20 sv1 rsyslogd-2177: imuxsock lost 1 messages from pid 3485 due to rate-limiting Dec 21 12:32:24 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 12:32:26 sv1 rsyslogd-2177: imuxsock lost 106 messages from pid 3485 due to rate-limiting Dec 21 13:32:20 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 13:32:21 sv1 rsyslogd-2177: imuxsock lost 34 messages from pid 3485 due to rate-limiting Dec 21 13:32:25 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 3485 due to rate-limiting Dec 21 13:32:27 sv1 rsyslogd-2177: imuxsock lost 23 messages from pid 3485 due to rate-limiting Dec 21 16:15:51 sv1 kernel: imklog 5.8.11, log source = /proc/kmsg started. Dec 21 16:15:51 sv1 rsyslogd: [origin software = "rsyslogd" swVersion = "5.8.11" x-pid ="1887" x-info = "http://www.rsyslog.com"] start Dec 21 16:25:50 sv1 kernel: imklog 5.8.11, log source = /proc/kmsg started. Dec 21 16:25:50 sv1 rsyslogd: [origin software = "rsyslogd" swVersion = "5.8.11" x-pid ="1889" x-info = "http://www.rsyslog.com"] start Dec 21 16:32:27 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 1854 due to rate-limiting Dec 21 16:32:28 sv1 rsyslogd-2177: imuxsock lost 1 messages from pid 1854 due to rate-limiting Dec 21 17:02:25 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 1854 due to rate-limiting Dec 21 17:02:26 sv1 rsyslogd-2177: imuxsock lost 12 messages from pid 1854 due to rate-limiting Dec 21 18:16:54 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 1854 due to rate-limiting Dec 21 18:16:55 sv1 rsyslogd-2177: imuxsock lost 36 messages from pid 1854 due to rate-limiting Dec 21 19:17:30 sv1 rsyslogd-2177: imuxsock begins to drop messages from pid 1854 due to rate-limiting Dec 21 19:18:02 sv1 rsyslogd-2177: imuxsock lost 54 messages from pid 1854 due to rate-limiting