配置11gR2 RAC SCAN
11G RAC scan即用DNA解析的IP地址，oracle推荐配置3个，这样可以起到均衡负载和冗余的作用.
系统情况： rac01,rac02
操作系统平台：red hat enterprise 5.4 2台虚拟机
这里 我们需要配置一个scan为 rac-scan的域名解析
配置步骤如下：
1. 我们设置rac01为DNS服务器
[root@rac01 etc]# ifconfig
eth0????? Link encap:Ethernet? HWaddr 00:0C:29:B5:38:5E?
????????? inet addr:192.168.0.18? Bcast:192.168.0.255? Mask:255.255.255.0
????????? inet6 addr: fe80::20c:29ff:feb5:385e/64 Scope:Link
????????? UP BROADCAST RUNNING MULTICAST? MTU:1500? Metric:1
????????? RX packets:2332291 errors:0 dropped:0 overruns:0 frame:0
????????? TX packets:1535201 errors:0 dropped:0 overruns:0 carrier:0
????????? collisions:0 txqueuelen:1000
????????? RX bytes:2347536563 (2.1 GiB)? TX bytes:1079658292 (1.0 GiB)
????????? Interrupt:185 Base address:0x1480
eth0:1??? Link encap:Ethernet? HWaddr 00:0C:29:B5:38:5E?
????????? inet addr:192.168.0.101? Bcast:192.168.0.255? Mask:255.255.255.0
????????? UP BROADCAST RUNNING MULTICAST? MTU:1500? Metric:1
????????? Interrupt:185 Base address:0x1480
eth1????? Link encap:Ethernet? HWaddr 00:0C:29:B5:38:68?
????????? inet addr:10.10.10.1? Bcast:10.10.10.255? Mask:255.255.255.0
????????? inet6 addr: fe80::20c:29ff:feb5:3868/64 Scope:Link
????????? UP BROADCAST RUNNING MULTICAST? MTU:1500? Metric:1
????????? RX packets:39950 errors:0 dropped:0 overruns:0 frame:0
????????? TX packets:61611 errors:0 dropped:0 overruns:0 carrier:0
????????? collisions:0 txqueuelen:1000
????????? RX bytes:15381230 (14.6 MiB)? TX bytes:46112067 (43.9 MiB)
????????? Interrupt:193 Base address:0x1800
lo??????? Link encap:Local Loopback?
????????? inet addr:127.0.0.1? Mask:255.0.0.0
????????? inet6 addr: ::1/128 Scope:Host
????????? UP LOOPBACK RUNNING? MTU:16436? Metric:1
????????? RX packets:54304 errors:0 dropped:0 overruns:0 frame:0
????????? TX packets:54304 errors:0 dropped:0 overruns:0 carrier:0
????????? collisions:0 txqueuelen:0
????????? RX bytes:10332630 (9.8 MiB)? TX bytes:10332630 (9.8 MiB)
?
从以上可以看出rac01的IP地址为:192.168.0.1
然后?配置 DNS named.conf 文件?
[root@rac01 named]# vi /var/named/chroot/etc/named.conf
options {
???? listen-on port 53 { any; };
???? listen-on-v6 port 53 { ::1; };
???? directory "/var/named";
???? dump-file "/var/named/data/cache_dump.db";
???? statistics-file "/var/named/data/named_stats.txt";
???? memstatistics-file "/var/named/data/named_mem_stats.txt";
???? query-source port 53;
???? query-source-v6 port 53;
???? allow-query { any; };
};
zone "." IN {
??? type hint;
??? file "named.ca";
};
zone "testenv.com" IN {
????? type master;
????? file "testenv.com.zone";
????? allow-update { none; };
};
zone "0.168.192.in-addr.arpa." IN {
?????? type master;
?????? file "0.168.192.in-addr.arpa.zone";
?????? allow-update { none; };
};
"/var/named/chroot/etc/named.conf" 29L, 697C
[root@rac01 etc]# dig? -t NS .
; <<>> DiG 9.3.6-P1-RedHat-9.3.6-4.P1.el5 <<>> -t NS .
;; global options:? printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 14850
;; flags: qr rd ra; QUERY: 1, ANSWER: 13, AUTHORITY: 0, ADDITIONAL: 14
;; QUESTION SECTION:
;.????????????????????????????? IN????? NS
;; ANSWER SECTION:
.?????????????????????? 513716? IN????? NS????? e.root-servers.net.
.?????????????????????? 513716? IN????? NS????? f.root-servers.net.
.?????????????????????? 513716? IN????? NS????? g.root-servers.net.
.?????????????????????? 513716? IN????? NS????? h.root-servers.net.
.?????????????????????? 513716? IN????? NS????? i.root-servers.net.
.?????????????????????? 513716? IN????? NS????? j.root-servers.net.
.?????????????????????? 513716? IN????? NS????? k.root-servers.net.
.?????????????????????? 513716? IN????? NS????? l.root-servers.net.
.?????????????????????? 513716? IN????? NS????? m.root-servers.net.
.?????????????????????? 513716? IN????? NS????? a.root-servers.net.
.?????????????????????? 513716? IN????? NS????? b.root-servers.net.
.?????????????????????? 513716? IN????? NS????? c.root-servers.net.
.?????????????????????? 513716? IN????? NS????? d.root-servers.net.
;; ADDITIONAL SECTION:
a.root-servers.net.???? 600116? IN????? A?????? 198.41.0.4
a.root-servers.net.???? 600116? IN????? AAAA??? 2001:503:ba3e::2:30
b.root-servers.net.???? 600116? IN????? A?????? 192.228.79.201
c.root-servers.net.???? 600116? IN????? A?????? 192.33.4.12
d.root-servers.net.???? 600116? IN????? A?????? 128.8.10.90
e.root-servers.net.???? 600116? IN????? A?????? 192.203.230.10
f.root-servers.net.???? 600116? IN????? A?????? 192.5.5.241
f.root-servers.net.???? 600116? IN????? AAAA??? 2001:500:2f::f
g.root-servers.net.???? 600116? IN????? A?????? 192.112.36.4
h.root-servers.net.???? 600116? IN????? A?????? 128.63.2.53
h.root-servers.net.???? 600116? IN????? AAAA??? 2001:500:1::803f:235
i.root-servers.net.???? 600116? IN????? A?????? 192.36.148.17
i.root-servers.net.???? 600116? IN????? AAAA??? 2001:7fe::53
j.root-servers.net.???? 600116? IN????? A?????? 192.58.128.30
;; Query time: 7 msec
;; SERVER: 192.168.0.18#53(192.168.0.18)
;; WHEN: Sun Jan? 2 09:09:56 2011
;; MSG SIZE? rcvd: 500
[root@rac01 etc]# dig? -t NS . >/var/named/named.ca
配置正解析文件?
[root@rac01 etc]#? vi /var/named/chroot/var/named/testenv.com.zone
$TTL 86400
@??????? IN????? SOA???? dns.testenv.com.??????? root.dns.testenv.com. (
???????????????????????? 20110102
???????????????????????? 1H
???????????????????????? 15M
???????????????????????? 1W
???????????????????????? 1D)
testenv.com.?? IN NS? dns.testenv.com.
dns???????????? ?IN A 192.168.0.18
www??????????? IN A 192.168.0.199
vip-rac01????? IN A 192.168.0.100
vip-rac02????? IN A 192.168.0.101
rac-scan?????? IN A 192.168.0.55
rac-scan?????? IN A 192.168.0.56
rac-scan?????? IN A 192.168.0.57
news?????????? IN CNAME www
~
~
~
~
"/var/named/chroot/var/named/testenv.com.zone" 18L, 595C written
配置反解析文件
[root@rac01 etc]# vi /var/named/chroot/var/named/0.168.192.in-addr.arpa.zone
$TTL 86400
@??? IN SOA dns.testenv.com. root.dns.testenv.com. (
????????????????? 20111102
????????????????? 3H
????????????????? 1H
????????????????? 1W
????????????????? 1H )
???? IN NS????? dns.testenv.com.
18?? IN PTR???? dns.testenv.com.
199? IN PTR???? www.testenv.com.
100? IN PTR???? vip-rac01.testenv.com.
101? IN PTR???? vip-rac02.testenv.com.
55?? IN PTR???? rac-scan.testenv.com.
56?? IN PTR???? rac-scan.testenv.com.
57?? IN PTR???? rac-scan.testenv.com.
~
~
~
~
"/var/named/chroot/var/named/0.168.192.in-addr.arpa.zone" 15L, 468C
?
配置DNS服务器所在地址：其中192.168.0.1为总的解析服务器,这里我们添加192.168.0.18为解析服务器
[root@rac01 etc]# vi /etc/resolv.conf
nameserver 192.168.0.18
nameserver 192.168.0.1
search localdomain testenv.com
~
~
"/etc/resolv.conf" 3L, 78C
配置hosts解析顺序:
[root@rac01 etc]# vi /etc/nsswitch.conf
#
# /etc/nsswitch.conf
#
# An example Name Service Switch config file. This file should be
# sorted with the most-used services at the beginning.
#
# The entry '[NOTFOUND=return]' means that the search for an
# entry should stop if the search in the previous entry turned
# up nothing. Note that if the search failed due to some other reason
# (like no NIS server responding) then the search continues with the
# next entry.
#
# Legal entries are:
#
#?????? nisplus or nis+???????? Use NIS+ (NIS version 3)
#?????? nis or yp?????????????? Use NIS (NIS version 2), also called YP
#?????? dns???????????????????? Use DNS (Domain Name Service)
#?????? files?????????????????? Use the local files
#?????? db????????????????????? Use the local database (.db) files
#?????? compat????????????????? Use NIS on compat mode
#?????? hesiod????????????????? Use Hesiod for user lookups
#?????? [NOTFOUND=return]?????? Stop searching if not found so far
#
# To use db, put the "db" in front of "files" for entries you want to be
# looked up first in the databases
#
# Example:
#passwd:??? db files nisplus nis
#shadow:??? db files nisplus nis
#group:???? db files nisplus nis
passwd:???? files
shadow:???? files
group:????? files
#hosts:???? db files nisplus nis dns
#hosts:????? files dns
hosts:?????? dns files nis
# Example - obey only what nisplus tells us...
#services:?? nisplus [NOTFOUND=return] files
"/etc/nsswitch.conf" 64L, 1724C
?
然后重新启动DNS服务
[root@rac01 etc]# service named restart
Stopping named: [? OK? ]
Starting named: [? OK? ]
[root@rac01 etc]# tail /var/log/messages
Jan? 2 09:14:02 rac01 named[29179]: listening on IPv4 interface eth0:1, 192.168.0.101#53
Jan? 2 09:14:02 rac01 named[29179]: listening on IPv4 interface eth1, 10.10.10.1#53
Jan? 2 09:14:02 rac01 named[29179]: /etc/named.conf:8: using specific query-source port suppresses port randomization and can be insecure.
Jan? 2 09:14:02 rac01 named[29179]: /etc/named.conf:9: using specific query-source port suppresses port randomization and can be insecure.
Jan? 2 09:14:02 rac01 named[29179]: command channel listening on 127.0.0.1#953
Jan? 2 09:14:02 rac01 named[29179]: command channel listening on ::1#953
Jan? 2 09:14:02 rac01 named[29179]: the working directory is not writable
Jan? 2 09:14:02 rac01 named[29179]: zone 0.168.192.in-addr.arpa/IN: loaded serial 20111102
Jan? 2 09:14:02 rac01 named[29179]: zone testenv.com/IN: loaded serial 20110102
Jan? 2 09:14:02 rac01 named[29179]: running
?
检查配置是否成功：试着解析rac-scan域名
[root@rac01 etc]# nslookup rac-scan
Server:???????? 192.168.0.18
Address:??????? 192.168.0.18#53
Name:?? rac-scan.testenv.com
Address: 192.168.0.55
Name:?? rac-scan.testenv.com
Address: 192.168.0.56
Name:?? rac-scan.testenv.com
Address: 192.168.0.57
[root@rac01 etc]# nslookup vip-rac01
Server:???????? 192.168.0.18
Address:??????? 192.168.0.18#53
Name:?? vip-rac01.testenv.com
Address: 192.168.0.100
[root@rac01 etc]# nslookup vip-rac02
Server:???????? 192.168.0.18
Address:??????? 192.168.0.18#53
Name:?? vip-rac02.testenv.com
Address: 192.168.0.101
反解析：
[root@rac01 etc]# nslookup 192.168.0.56
Server:???????? 192.168.0.18
Address:??????? 192.168.0.18#53
56.0.168.192.in-addr.arpa?????? name = rac-scan.testenv.com.
[root@rac01 etc]#
看来配置成功!
然后再在rac02上做相关配置:
[root@rac02 ~]# vi /etc/nsswitch.conf
#
# /etc/nsswitch.conf
#
# An example Name Service Switch config file. This file should be
# sorted with the most-used services at the beginning.
#
# The entry '[NOTFOUND=return]' means that the search for an
# entry should stop if the search in the previous entry turned
# up nothing. Note that if the search failed due to some other reason
# (like no NIS server responding) then the search continues with the
# next entry.
#
# Legal entries are:
#
#?????? nisplus or nis+???????? Use NIS+ (NIS version 3)
#?????? nis or yp?????????????? Use NIS (NIS version 2), also called YP
#?????? dns???????????????????? Use DNS (Domain Name Service)
#?????? files?????????????????? Use the local files
#?????? db????????????????????? Use the local database (.db) files
#?????? compat????????????????? Use NIS on compat mode
#?????? hesiod????????????????? Use Hesiod for user lookups
#?????? [NOTFOUND=return]?????? Stop searching if not found so far
#
# To use db, put the "db" in front of "files" for entries you want to be
# looked up first in the databases
#
# Example:
#passwd:??? db files nisplus nis
#shadow:??? db files nisplus nis
#group:???? db files nisplus nis
passwd:???? files
shadow:???? files
group:????? files
#hosts:???? db files nisplus nis dns
#hosts:???? files dns
hosts:????? dns files nis
# Example - obey only what nisplus tells us...
#services:?? nisplus [NOTFOUND=return] files
"/etc/nsswitch.conf" 64L, 1722C
[root@rac02 ~]# vi /etc/resolv.conf
; generated by /sbin/dhclient-script
nameserver 192.168.0.18
nameserver 192.168.0.1
search localdomain testenv.com
~
~
"/etc/resolv.conf" 4L, 115C
?
[root@rac02 ~]# nslookup rac-scan
Server:???????? 192.168.0.18
Address:??????? 192.168.0.18#53
Name:?? rac-scan.testenv.com
Address: 192.168.0.56
Name:?? rac-scan.testenv.com
Address: 192.168.0.57
Name:?? rac-scan.testenv.com
Address: 192.168.0.55
[root@rac02 ~]#
[root@rac02 ~]# nslookup vip-rac01
Server:???????? 192.168.0.18
Address:??????? 192.168.0.18#53
Name:?? vip-rac01.testenv.com
Address: 192.168.0.100
[root@rac02 ~]# nslookup vip-rac02
Server:???????? 192.168.0.18
Address:??????? 192.168.0.18#53
Name:?? vip-rac02.testenv.com
Address: 192.168.0.101
[root@rac02 ~]# nslookup 192.168.0.56
Server:???????? 192.168.0.18
Address:??????? 192.168.0.18#53
56.0.168.192.in-addr.arpa?????? name = rac-scan.testenv.com.
[root@rac02 ~]#
?
rac02也可以正确解析SCAN域名！
这样一个正反解析的SCAN域名就配置成功了.......
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注意：在安装11Gr2 RAC集群时，配置其中的一个节点作为DNS服务器是不被支持的，安装过程中会出错
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