DNS 引起经典RAC故障
作者:吴伟龙(PrudentWoo)
一、环境介绍:
这是一套四年前部署的RAC系统,之前运行一直很好,没有出过问题,平时基本处于无人管的状态。
OS:Redhat EnterPrise Linux 5.8 x86_x64
DB:Oracle Database EnterPrise 11.2.0.4
GI:Oracle Grid Infrastructure 11.2.0.4
二、问题描述:
昨天临近下班接到现场人员故障请求,描述为数据库无法连接,报ORA-12547:TNS: lost CONNECT。当时第一反应是网络和监听故障,让现场人员进行tnsping和ping都是正常的。
三、问题现象:
我到达现场后,首先查看了数据库的状态,发现数据库实例是停止运行状态,并且从日志中看不出明显报错;
数据库日志:
- Starting up:
- Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
- With the Partitioning, Real Application Clusters, OLAP, Data Mining
- and Real Application Testing options.
- ORACLE_HOME = /u01/app/oracle/11.2.0.4/product/db_1
- System name: Linux
- Node name: db01
- Release: 3.8.13-44.1.1.el6uek.x86_64
- Version: #2 SMP Wed Sep 10 06:10:25 PDT 2014
- Machine: x86_64
- VM name: VMWare Version: 6
- Using parameter settings in server-side pfile /u01/app/oracle/11.2.0.4/product/db_1/dbs/initwoo1.ora
- System parameters with non-default values:
- processes = 600
- sessions = 922
- spfile = "+DATA/woo/spfilewoo.ora"
- nls_language = "SIMPLIFIED CHINESE"
- nls_territory = "CHINA"
- memory_target = 1584M
- control_files = "+DATA/woo/controlfile/current.260.930748953"
- control_files = "+FRA01/woo/controlfile/current.256.930748953"
- db_block_size = 8192
- compatible = "11.2.0.4.0"
- cluster_database = TRUE
- db_create_file_dest = "+DATA"
- db_recovery_file_dest = "+FRA01"
- db_recovery_file_dest_size= 4407M
- thread = 1
- undo_tablespace = "UNDOTBS1"
- instance_number = 1
- remote_login_passwordfile= "EXCLUSIVE"
- db_domain = ""
- dispatchers = "(PROTOCOL=TCP) (SERVICE=wooXDB)"
- remote_listener = "scan.prudentwoo.com:1521"
- audit_file_dest = "/u01/app/oracle/admin/woo/adump"
- audit_trail = "DB"
- db_name = "woo"
- open_cursors = 300
- diagnostic_dest = "/u01/app/oracle"
- Cluster communication is configured to use the following interface(s) for this instance
- 169.254.51.38
- 169.254.243.157
- cluster interconnect IPC version:Oracle UDP/IP (generic)
- IPC Vendor 1 proto 2
- Fri Dec 16 15:24:55 2016
- USER (ospid: 4044): terminating the instance due to error 119
- Instance terminated by USER, pid = 4044
数据库状态:
- [oracle@db01 ~]$ crsctl status res -t
- --------------------------------------------------------------------------------
- NAME TARGET STATE SERVER STATE_DETAILS
- --------------------------------------------------------------------------------
- Local Resources
- --------------------------------------------------------------------------------
- ora.BAK01.dg
- ONLINE ONLINE db01
- ONLINE ONLINE db02
- ora.DATA.dg
- ONLINE ONLINE db01
- ONLINE ONLINE db02
- ora.FRA01.dg
- ONLINE ONLINE db01
- ONLINE ONLINE db02
- ora.LISTENER.lsnr
- ONLINE ONLINE db01
- ONLINE ONLINE db02
- ora.OCR_VOT.dg
- ONLINE ONLINE db01
- ONLINE ONLINE db02
- ora.asm
- ONLINE ONLINE db01 Started
- ONLINE ONLINE db02 Started
- ora.gsd
- OFFLINE OFFLINE db01
- OFFLINE OFFLINE db02
- ora.net1.network
- ONLINE ONLINE db01
- ONLINE ONLINE db02
- ora.ons
- ONLINE ONLINE db01
- ONLINE ONLINE db02
- --------------------------------------------------------------------------------
- Cluster Resources
- --------------------------------------------------------------------------------
- ora.LISTENER_SCAN1.lsnr
- 1 ONLINE ONLINE db02
- ora.LISTENER_SCAN2.lsnr
- 1 ONLINE ONLINE db01
- ora.LISTENER_SCAN3.lsnr
- 1 ONLINE ONLINE db01
- ora.cvu
- 1 ONLINE ONLINE db01
- ora.db01.vip
- 1 ONLINE ONLINE db01
- ora.db02.vip
- 1 ONLINE ONLINE db02
- ora.oc4j
- 1 ONLINE ONLINE db01
- ora.scan1.vip
- 1 ONLINE ONLINE db02
- ora.scan2.vip
- 1 ONLINE ONLINE db01
- ora.scan3.vip
- 1 ONLINE ONLINE db01
- ora.woo.db
- 1 ONLINE OFFLINE Instance Shutdown
- 2 ONLINE OFFLINE Instance Shutdown
- [oracle@db01 ~]$ srvctl status database -d woo
- Instance woo1 is not running on node db01
- Instance woo2 is not running on node db02
四、手工带起数据库:
- [oracle@db01 trace]$ srvctl start database -d woo
- PRCR-1079 : Failed to start resource ora.woo.db
- CRS-5017: The resource action "ora.woo.db start" encountered the following error:
- ORA-00119: invalid specification for system parameter REMOTE_LISTENER
- ORA-00132: syntax error or unresolved network name 'scan.prudentwoo.com:1521'
- . For details refer to "(:CLSN00107:)" in "/u01/app/11.2.0.4/product/grid/log/db02/agent/crsd/oraagent_oracle/oraagent_oracle.log".
- CRS-5017: The resource action "ora.woo.db start" encountered the following error:
- ORA-00119: invalid specification for system parameter REMOTE_LISTENER
- ORA-00132: syntax error or unresolved network name 'scan.prudentwoo.com:1521'
- . For details refer to "(:CLSN00107:)" in "/u01/app/11.2.0.4/product/grid/log/db01/agent/crsd/oraagent_oracle/oraagent_oracle.log".
- CRS-2674: Start of 'ora.woo.db' on 'db02' failed
- CRS-2674: Start of 'ora.woo.db' on 'db01' failed
- CRS-2632: There are no more servers to try to place resource 'ora.woo.db' on that would satisfy its placement policy
日志信息:
- alert.log:
- [oracle@db01 trace]$ tail -0f alert_woo1.log
- Fri Dec 16 15:37:08 2016
- Starting ORACLE instance (normal)
- LICENSE_MAX_SESSION = 0
- LICENSE_SESSIONS_WARNING = 0
- Initial number of CPU is 2
- Private Interface 'eth1:1' configured from GPnP for use as a private interconnect.
- [name='eth1:1', type=1, ip=169.254.51.38, mac=00-0c-29-7c-44-ca, net=169.254.0.0/17, mask=255.255.128.0, use=haip:cluster_interconnect/62]
- Private Interface 'eth2:1' configured from GPnP for use as a private interconnect.
- [name='eth2:1', type=1, ip=169.254.243.157, mac=00-0c-29-7c-44-d4, net=169.254.128.0/17, mask=255.255.128.0, use=haip:cluster_interconnect/62]
- Public Interface 'eth0' configured from GPnP for use as a public interface.
- [name='eth0', type=1, ip=192.168.84.11, mac=00-0c-29-7c-44-c0, net=192.168.84.0/24, mask=255.255.255.0, use=public/1]
- Public Interface 'eth0:1' configured from GPnP for use as a public interface.
- [name='eth0:1', type=1, ip=192.168.84.22, mac=00-0c-29-7c-44-c0, net=192.168.84.0/24, mask=255.255.255.0, use=public/1]
- Public Interface 'eth0:3' configured from GPnP for use as a public interface.
- [name='eth0:3', type=1, ip=192.168.84.20, mac=00-0c-29-7c-44-c0, net=192.168.84.0/24, mask=255.255.255.0, use=public/1]
- Public Interface 'eth0:5' configured from GPnP for use as a public interface.
- [name='eth0:5', type=1, ip=192.168.84.13, mac=00-0c-29-7c-44-c0, net=192.168.84.0/24, mask=255.255.255.0, use=public/1]
- CELL communication is configured to use 0 interface(s):
- CELL IP affinity details:
- NUMA status: non-NUMA system
- cellaffinity.ora status: N/A
- CELL communication will use 1 IP group(s):
- Grp 0:
- Picked latch-free SCN scheme 3
- Using LOG_ARCHIVE_DEST_1 parameter default value as USE_DB_RECOVERY_FILE_DEST
- Autotune of undo retention is turned on.
- LICENSE_MAX_USERS = 0
- SYS auditing is disabled
- Starting up:
- Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
- With the Partitioning, Real Application Clusters, OLAP, Data Mining
- and Real Application Testing options.
- ORACLE_HOME = /u01/app/oracle/11.2.0.4/product/db_1
- System name: Linux
- Node name: db01
- Release: 3.8.13-44.1.1.el6uek.x86_64
- Version: #2 SMP Wed Sep 10 06:10:25 PDT 2014
- Machine: x86_64
- VM name: VMWare Version: 6
- Using parameter settings in server-side pfile /u01/app/oracle/11.2.0.4/product/db_1/dbs/initwoo1.ora
- System parameters with non-default values:
- processes = 600
- sessions = 922
- spfile = "+DATA/woo/spfilewoo.ora"
- nls_language = "SIMPLIFIED CHINESE"
- nls_territory = "CHINA"
- memory_target = 1584M
- control_files = "+DATA/woo/controlfile/current.260.930748953"
- control_files = "+FRA01/woo/controlfile/current.256.930748953"
- db_block_size = 8192
- compatible = "11.2.0.4.0"
- cluster_database = TRUE
- db_create_file_dest = "+DATA"
- db_recovery_file_dest = "+FRA01"
- db_recovery_file_dest_size= 4407M
- thread = 1
- undo_tablespace = "UNDOTBS1"
- instance_number = 1
- remote_login_passwordfile= "EXCLUSIVE"
- db_domain = ""
- dispatchers = "(PROTOCOL=TCP) (SERVICE=wooXDB)"
- remote_listener = "scan.prudentwoo.com:1521"
- audit_file_dest = "/u01/app/oracle/admin/woo/adump"
- audit_trail = "DB"
- db_name = "woo"
- open_cursors = 300
- diagnostic_dest = "/u01/app/oracle"
- Cluster communication is configured to use the following interface(s) for this instance
- 169.254.51.38
- 169.254.243.157
- cluster interconnect IPC version:Oracle UDP/IP (generic)
- IPC Vendor 1 proto 2
- Fri Dec 16 15:37:49 2016
- USER (ospid: 6043): terminating the instance due to error 119
- Instance terminated by USER, pid = 6043
五、问题分析:
我从启动数据库来看,发现数据库此时无法正常启动,并随着报ORA-00132,日志报error 119。
根据启动提示可以将问题定位到scan,因scan故障引起数据库无法正常启动。
六、检查scan配置信息:
- #check scan info:
- [oracle@db01 ~]$ srvctl config scan
- SCAN name: scan.prudentwoo.com, Network: 1/192.168.84.0/255.255.255.0/eth0
- SCAN VIP name: scan1, IP: /scan.prudentwoo.com/192.168.84.21
- SCAN VIP name: scan2, IP: /scan.prudentwoo.com/192.168.84.22
- SCAN VIP name: scan3, IP: /scan.prudentwoo.com/192.168.84.20
- [oracle@db01 ~]$ ping 192.168.84.20 -c 2
- PING 192.168.84.20 (192.168.84.20) 56(84) bytes of data.
- 64 bytes from 192.168.84.20: icmp_seq=1 ttl=64 time=0.032 ms
- 64 bytes from 192.168.84.20: icmp_seq=2 ttl=64 time=0.039 ms
- --- 192.168.84.20 ping statistics ---
- 2 packets transmitted, 2 received, 0% packet loss, time 1000ms
- rtt min/avg/max/mdev = 0.032/0.035/0.039/0.006 ms
- [oracle@db01 ~]$ ping 192.168.84.21 -c 2
- PING 192.168.84.21 (192.168.84.21) 56(84) bytes of data.
- 64 bytes from 192.168.84.21: icmp_seq=1 ttl=64 time=0.231 ms
- 64 bytes from 192.168.84.21: icmp_seq=2 ttl=64 time=0.292 ms
- --- 192.168.84.21 ping statistics ---
- 2 packets transmitted, 2 received, 0% packet loss, time 1001ms
- rtt min/avg/max/mdev = 0.231/0.261/0.292/0.034 ms
- [oracle@db01 ~]$ ping 192.168.84.22 -c 2
- PING 192.168.84.22 (192.168.84.22) 56(84) bytes of data.
- 64 bytes from 192.168.84.22: icmp_seq=1 ttl=64 time=0.024 ms
- 64 bytes from 192.168.84.22: icmp_seq=2 ttl=64 time=0.034 ms
- --- 192.168.84.22 ping statistics ---
- 2 packets transmitted, 2 received, 0% packet loss, time 999ms
- rtt min/avg/max/mdev = 0.024/0.029/0.034/0.005 ms
- [oracle@db01 ~]$ ping scan.prudentwoo.com -c 2
- ping: unknown host scan.prudentwoo.com
我们可以看到,现在scan对应的三个地址都是通的,说明SCAN的服务是好的,但是ping scan所对应的域名的时候报无法找到主机,无法解析域名,那么下一步可以定位应该是域名服务出问题了。
七、在两台数据库服务器上检查域名(dns)服务,结果是域名服务器没有在这两台数据服务器上:
- #check dns client and server:
- [oracle@db01 ~]$ /sbin/chkconfig --list|grep named
- [oracle@db01 ~]$ ssh db02 '/sbin/chkconfig --list|grep named'
- [oracle@db01 ~]$
- check dns client:
- [oracle@db01 ~]$ cat /etc/resolv.conf
- search prudentwoo.com
- nameserver 192.168.84.15
八、根据resolv.conf配置找到真正的域名服务器,发现域名域名服务器hang住:
- [oracle@db01 ~]$ ping 192.168.84.15 -c 2
- PING 192.168.84.15 (192.168.84.15) 56(84) bytes of data.
- From 192.168.84.11 icmp_seq=1 Destination Host Unreachable
- From 192.168.84.11 icmp_seq=2 Destination Host Unreachable
- --- 192.168.84.15 ping statistics ---
- 2 packets transmitted, 0 received, +2 errors, 100% packet loss, time 3007ms
- pipe 2
九、修复域名服务器,现在可以正常解析:
- [oracle@db01 ~]$ ping scan.prudentwoo.com -c 2
- PING scan.prudentwoo.com (192.168.84.21) 56(84) bytes of data.
- 64 bytes from scan.prudentwoo.com (192.168.84.21): icmp_seq=1 ttl=64 time=0.494 ms
- 64 bytes from scan.prudentwoo.com (192.168.84.21): icmp_seq=2 ttl=64 time=0.289 ms
- --- scan.prudentwoo.com ping statistics ---
- 2 packets transmitted, 2 received, 0% packet loss, time 1001ms
- rtt min/avg/max/mdev = 0.289/0.391/0.494/0.104 ms
十、再次启动数据库:
- [oracle@db01 ~]$ srvctl start database -d woo
- [oracle@db01 ~]$ srvctl status database -d woo
- Instance woo1 is running on node db01
- Instance woo2 is running on node db02
- [oracle@db01 ~]$ srvctl config database -d woo
- Database unique name: woo
- Database name: woo
- Oracle home: /u01/app/oracle/11.2.0.4/product/db_1
- Oracle user: oracle
- Spfile: +DATA/woo/spfilewoo.ora
- Domain:
- Start options: open
- Stop options: immediate
- Database role: PRIMARY
- Management policy: AUTOMATIC
- Server pools: woo
- Database instances: woo1,woo2
- Disk Groups: DATA,FRA01
- Mount point paths:
- Services:
- Type: RAC
- Database is administrator managed
能正常启动,故障修复。
从整个问题的处理思路来看该故障不仅考验解决数据库故障能力,同时安装,基本运行原理都有考察到,当然考验更多的应该还是操作系统和DNS服务的深入理解。
当然我是很庆幸的,出于职业敏感度,一堆报错中瞬间发现问题根源ORA-00132,而没有从其它报错信息入手。