我想测试来自其他主机的索引功能的执行，因为这个功能在hadoop程序中没有完全正确地实现。但是我遇到了从其他主机连接到数据库的问题，如下所述。我不明白什么是问题。
我写了以下java程序
import java.io.*;
import java.util.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.logging.Level;
import java.util.*;
public class Sample {
public static void main (String[] args) throws IOException {
int CountComputers;
FileInputStream fstream = new FileInputStream(
"/export/hadoop-1.0.1/bin/countcomputers.txt");
BufferedReader br = new BufferedReader(new InputStreamReader(fstream));
String result=br.readLine();
CountComputers=Integer.parseInt(result);
input.close();
fstream.close();
Connection con = null;
Statement st = null;
ResultSet rs = null;
String url = "jdbc:postgresql://192.168.1.8:5432/NexentaSearch";
String user = "postgres";
String password = "valter89";
//Class.forName("org.postgresql.Driver");
ArrayList<String> paths = new ArrayList<String>();
try
{
Class.forName("org.postgresql.Driver");
con = DriverManager.getConnection(url, user, password);
st = con.createStatement();
rs = st.executeQuery("select path from tasks order by id");
while (rs.next()) { paths.add(rs.getString(1)); };
PrintWriter zzz = null;
try
{
zzz = new PrintWriter(new FileOutputStream("/export/hadoop-1.0.1/bin/readwaysfromdatabase.txt"));
}
catch(FileNotFoundException e)
{
System.out.println("Error");
System.exit(0);
}
for (int i=0; i<paths.size(); i++)
{
zzz.println("paths[i]=" + paths.get(i) + "\n");
}
zzz.close();
}
catch (SQLException e)
{
System.out.println("Connection Failed! Check output console");
e.printStackTrace();
}
catch (ClassNotFoundException e)
{
e.printStackTrace();
}
}
}
我通过命令
启动了Sample.jar./java -jar -Djava.library.path=/opt/jdk1.7.0_06/lib /Samplejavaprogram/Sample.jar
因此我收到了以下消息
Connection Failed! Check output console
org.postgresql.util.PSQLException: Connection refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:136)
at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:66)
at org.postgresql.jdbc2.AbstractJdbc2Connection.<init>(AbstractJdbc2Connection.java:125)
at org.postgresql.jdbc3.AbstractJdbc3Connection.<init>(AbstractJdbc3Connection.java:30)
at org.postgresql.jdbc3.Jdbc3Connection.<init>(Jdbc3Connection.java:24)
at org.postgresql.Driver.makeConnection(Driver.java:393)
at org.postgresql.Driver.connect(Driver.java:267)
at java.sql.DriverManager.getConnection(DriverManager.java:579)
at java.sql.DriverManager.getConnection(DriverManager.java:221)
at Sample.main(Sample.java:33)
Caused by: java.net.ConnectException: Connection timed out
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:391)
at java.net.Socket.connect(Socket.java:579)
at java.net.Socket.connect(Socket.java:528)
at java.net.Socket.<init>(Socket.java:425)
at java.net.Socket.<init>(Socket.java:208)
at org.postgresql.core.PGStream.<init>(PGStream.java:62)
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:76)
... 9 more
我从地址为192.168.1.10的主机启动了该文件。帮助消除错误。在什么原因导致错误？有什么需要做的？
netstat -a
UDP: IPv4
Local Address Remote Address State
-------------------- -------------------- ----------
*.bootpc Idle
*.dhcpv6-client Idle
*.* Unbound
*.* Unbound
*.sunrpc Idle
*.* Unbound
*.38606 Idle
*.sunrpc Idle
*.* Unbound
*.40712 Idle
*.* Unbound
*.* Unbound
*.* Unbound
*.54122 Idle
*.41742 Idle
*.* Unbound
*.lockd Idle
*.lockd Idle
*.59670 Idle
*.42840 Idle
*.43065 Idle
*.39546 Idle
*.34243 Idle
*.35383 Idle
*.40746 Idle
*.40832 Idle
192.168.1.2.bootpc Idle
*.mdns Idle
*.mdns Idle
192.168.1.2.ntp Idle
*.snmpd Idle
*.ntp Idle
*.ntp Idle
localhost.localdomain.ntp Idle
myhost2.ntp Idle
UDP: IPv6
Local Address Remote Address State If
--------------------------------- --------------------------------- ---------- -----
*.dhcpv6-client Idle
*.* Unbound
localhost.44111 localhost.44111 Connected
*.sunrpc Idle
*.* Unbound
*.38606 Idle
*.54122 Idle
*.* Unbound
*.lockd Idle
*.42840 Idle
*.39546 Idle
*.35383 Idle
*.40832 Idle
*.ntp Idle
localhost.ntp Idle
TCP: IPv4
Local Address Remote Address Swind Send-Q Rwind Recv-Q State
-------------------- -------------------- ----- ------ ----- ------ -----------
localhost.localdomain.4999 *.* 0 0 128000 0 LISTEN
*.2001 *.* 0 0 128000 0 LISTEN
*.2002 *.* 0 0 128000 0 LISTEN
*.2003 *.* 0 0 128000 0 LISTEN
*.16049 *.* 0 0 128000 0 LISTEN
*.5432 *.* 0 0 128000 0 LISTEN
*.sunrpc *.* 0 0 128000 0 LISTEN
*.* *.* 0 0 128000 0 IDLE
*.sunrpc *.* 0 0 128000 0 LISTEN
*.* *.* 0 0 128000 0 IDLE
*.54002 *.* 0 0 128000 0 LISTEN
*.49023 *.* 0 0 128000 0 LISTEN
*.55493 *.* 0 0 1049200 0 LISTEN
*.46659 *.* 0 0 1048952 0 LISTEN
*.lockd *.* 0 0 1049200 0 LISTEN
*.lockd *.* 0 0 1048952 0 LISTEN
*.45361 *.* 0 0 128000 0 LISTEN
localhost.localdomain.36084 localhost.localdomain.2001 65440 0 139264 0 ESTABLISHED
*.53943 *.* 0 0 128000 0 LISTEN
localhost.localdomain.2001 localhost.localdomain.36084 139060 0 130880 0 ESTABLISHED
localhost.localdomain.44644 localhost.localdomain.2012 34765 0 139264 0 ESTABLISHED
localhost.localdomain.2012 localhost.localdomain.44644 139060 0 139060 0 ESTABLISHED
*.36068 *.* 0 0 128000 0 LISTEN
*.57055 *.* 0 0 128000 0 LISTEN
*.login *.* 0 0 128000 0 LISTEN
*.finger *.* 0 0 128000 0 LISTEN
*.telnet *.* 0 0 128000 0 LISTEN
*.shell *.* 0 0 128000 0 LISTEN
*.40524 *.* 0 0 128000 0 LISTEN
*.60838 *.* 0 0 128000 0 LISTEN
*.47648 *.* 0 0 128000 0 LISTEN
*.56894 *.* 0 0 128000 0 LISTEN
*.48461 *.* 0 0 128000 0 LISTEN
*.53672 *.* 0 0 128000 0 LISTEN
*.42108 *.* 0 0 128000 0 LISTEN
*.63720 *.* 0 0 128000 0 LISTEN
*.ssh *.* 0 0 128000 0 LISTEN
localhost.localdomain.smtp *.* 0 0 128000 0 LISTEN
localhost.localdomain.submission *.* 0 0 128000 0 LISTEN
*.80 *.* 0 0 128000 0 LISTEN
*.* *.* 0 0 128000 0 IDLE
*.2000 *.* 0 0 128000 0 LISTEN
*.* *.* 0 0 128000 0 IDLE
*.443 *.* 0 0 128000 0 LISTEN
*.* *.* 0 0 128000 0 IDLE
localhost.localdomain.38137 localhost.localdomain.2003 65440 0 139264 0 ESTABLISHED
localhost.localdomain.2003 localhost.localdomain.38137 139060 0 130880 0 ESTABLISHED
localhost.localdomain.63918 localhost.localdomain.2001 65440 0 139264 0 ESTABLISHED
localhost.localdomain.2001 localhost.localdomain.63918 139060 0 130880 0 ESTABLISHED
myhost2.ssh 192.168.1.4.7431 65548 0 128480 0 ESTABLISHED
localhost.localdomain.34057 localhost.localdomain.2001 65440 0 139264 0 ESTABLISHED
localhost.localdomain.2001 localhost.localdomain.34057 139060 0 130880 0 ESTABLISHED
localhost.localdomain.37015 localhost.localdomain.2001 65440 0 139264 0 ESTABLISHED
localhost.localdomain.2001 localhost.localdomain.37015 139060 0 130880 0 ESTABLISHED
*.2011 *.* 0 0 131072 0 LISTEN
localhost.localdomain.36598 localhost.localdomain.2002 65440 0 139264 0 ESTABLISHED
localhost.localdomain.2002 localhost.localdomain.36598 139060 0 130880 0 ESTABLISHED
localhost.localdomain.4000 *.* 0 0 131072 0 LISTEN
localhost.localdomain.53161 localhost.localdomain.2011 34765 0 139264 0 ESTABLISHED
localhost.localdomain.2011 localhost.localdomain.53161 139060 0 139060 0 ESTABLISHED
localhost.localdomain.43878 localhost.localdomain.2001 65440 0 139264 0 ESTABLISHED
localhost.localdomain.2001 localhost.localdomain.43878 139060 0 130880 0 ESTABLISHED
localhost.localdomain.50976 localhost.localdomain.2001 65440 0 139264 0 ESTABLISHED
localhost.localdomain.2001 localhost.localdomain.50976 139060 0 130880 0 ESTABLISHED
localhost.localdomain.62633 localhost.localdomain.2012 34765 0 139264 0 ESTABLISHED
localhost.localdomain.2012 localhost.localdomain.62633 139060 0 139060 0 ESTABLISHED
*.2012 *.* 0 0 131072 0 LISTEN
localhost.localdomain.34418 localhost.localdomain.2012 34765 0 139264 0 ESTABLISHED
localhost.localdomain.2012 localhost.localdomain.34418 139060 0 139060 0 ESTABLISHED
localhost.localdomain.34356 localhost.localdomain.2011 34765 0 139264 0 ESTABLISHED
localhost.localdomain.2011 localhost.localdomain.34356 139060 0 139060 0 ESTABLISHED
localhost.localdomain.62884 localhost.localdomain.2001 65440 0 139264 0 ESTABLISHED
localhost.localdomain.2001 localhost.localdomain.62884 139060 0 130880 0 ESTABLISHED
localhost.localdomain.52603 localhost.localdomain.2011 34765 0 139264 0 ESTABLISHED
localhost.localdomain.2011 localhost.localdomain.52603 139060 0 139060 0 ESTABLISHED
localhost.localdomain.35345 localhost.localdomain.2001 65440 0 139264 0 ESTABLISHED
localhost.localdomain.2001 localhost.localdomain.35345 139060 0 130880 0 ESTABLISHED
localhost.localdomain.49022 localhost.localdomain.2001 130880 0 139264 0 TIME_WAIT
localhost.localdomain.42797 localhost.localdomain.2001 130880 0 139264 0 TIME_WAIT
localhost.localdomain.46312 localhost.localdomain.2001 130880 0 139264 0 TIME_WAIT
TCP: IPv6
Local Address Remote Address Swind Send-Q Rwind Recv-Q State If
--------------------------------- --------------------------------- ----- ------ ----- ------ ----------- -----
*.5432 *.* 0 0 128000 0 LISTEN
*.sunrpc *.* 0 0 128000 0 LISTEN
*.* *.* 0 0 128000 0 IDLE
*.54002 *.* 0 0 128000 0 LISTEN
*.55493 *.* 0 0 1049200 0 LISTEN
*.lockd *.* 0 0 1049200 0 LISTEN
*.53943 *.* 0 0 128000 0 LISTEN
*.57055 *.* 0 0 128000 0 LISTEN
*.login *.* 0 0 128000 0 LISTEN
*.finger *.* 0 0 128000 0 LISTEN
*.telnet *.* 0 0 128000 0 LISTEN
*.shell *.* 0 0 128000 0 LISTEN
*.60838 *.* 0 0 128000 0 LISTEN
*.56894 *.* 0 0 128000 0 LISTEN
*.53672 *.* 0 0 128000 0 LISTEN
*.63720 *.* 0 0 128000 0 LISTEN
*.ssh *.* 0 0 128000 0 LISTEN
localhost.smtp *.* 0 0 128000 0 LISTEN
*.80 *.* 0 0 128000 0 LISTEN
*.2000 *.* 0 0 128000 0 LISTEN
*.443 *.* 0 0 128000 0 LISTEN
Active UNIX domain sockets
Address Type Vnode Conn Local Addr Remote Addr
ffffff0119f107b8 stream-ord 00000000 00000000
ffffff0119f10b68 stream-ord 00000000 00000000
ffffff0119214050 stream-ord 00000000 00000000
ffffff0119214400 stream-ord 00000000 00000000
ffffff0119214b60 stream-ord 00000000 00000000
ffffff0114119048 stream-ord 00000000 00000000
ffffff01141193f8 stream-ord ffffff011950e580 00000000 /tmp/dbus-3YiNfXlgwn
ffffff01141197a8 stream-ord ffffff0119217e40 00000000 /tmp/dbus-7BNzAEnmYY
ffffff0114119b58 stream-ord ffffff0114118e40 00000000 /var/run/mDNSResponder
ffffff01138b2040 stream-ord 00000000 00000000 /var/run/dbus/system_bus_socket
ffffff01138b23f0 stream-ord 00000000 ffffff0111d0e780 /var/run/dbus/system_bus_socket
ffffff01138b27a0 stream-ord 00000000 00000000 /var/run/dbus/system_bus_socket
ffffff01138b2b50 stream-ord 00000000 ffffff0111d0e780 /var/run/dbus/system_bus_socket
ffffff0113059038 stream-ord ffffff0113835140 00000000 /var/run/.inetd.uds
ffffff01130593e8 stream-ord 00000000 ffffff0112c5f880 /var/run/hald/dbus-9g2E5zdff9
ffffff0113059798 stream-ord 00000000 00000000 /var/run/hald/dbus-9g2E5zdff9
ffffff0113059b48 dgram ffffff01130b2e00 00000000 /var/run/in.ndpd_mib
ffffff011306d030 stream-ord ffffff0112bb5280 00000000 /var/run/in.ndpd_ipadm
ffffff011306d3e0 stream-ord 00000000 00000000 /var/run/hald/dbus-9g2E5zdff9
ffffff011306d790 stream-ord 00000000 00000000 /var/run/hald/dbus-9g2E5zdff9
ffffff011306db40 stream-ord 00000000 ffffff0112c5f880 /var/run/hald/dbus-9g2E5zdff9
ffffff0112fcb028 stream-ord 00000000 ffffff0112c5f880 /var/run/hald/dbus-9g2E5zdff9
ffffff0112fcb3d8 stream-ord 00000000 00000000 /var/run/hald/dbus-9g2E5zdff9
ffffff0112fcb788 stream-ord 00000000 ffffff0112c5f880 /var/run/hald/dbus-9g2E5zdff9
ffffff0112fcbb38 stream-ord ffffff0112fd4080 00000000 /tmp/.s.PGSQL.5432
ffffff01122c4020 stream-ord 00000000 00000000 /var/run/hald/dbus-F83hT9CGSX
ffffff01122c43d0 stream-ord 00000000 ffffff0112c5f280 /var/run/hald/dbus-F83hT9CGSX
ffffff01122c4780 stream-ord ffffff0112c5f280 00000000 /var/run/hald/dbus-F83hT9CGSX
ffffff01122c4b30 stream-ord 00000000 00000000
ffffff0112294018 stream-ord 00000000 00000000
ffffff01122943c8 stream-ord ffffff0112c5f880 00000000 /var/run/hald/dbus-9g2E5zdff9
ffffff0112294778 stream-ord 00000000 00000000
ffffff0112294b28 stream-ord 00000000 00000000
ffffff0112278010 stream-ord ffffff01122c7880 00000000 /tmp/dbus-PuCCfO9I4C
ffffff01122783c0 stream-ord 00000000 00000000
ffffff0112278770 stream-ord 00000000 00000000
ffffff0112278b20 stream-ord ffffff01122a0b40 00000000 /tmp/dbus-tfcmjjMClq
ffffff0111d08008 stream-ord 00000000 00000000
ffffff0111d083b8 stream-ord 00000000 00000000
ffffff0111d08768 stream-ord ffffff01121a2b40 00000000 /tmp/dbus-cEAGQX2WDo
ffffff0111d08b18 stream-ord ffffff0111d0e780 00000000 /var/run/dbus/system_bus_socket
推出Postgresql？
答案 0 :(得分：7)
错误“检查主机名和端口是否正确以及postmaster是否接受TCP / IP连接。”表明：
Postgres未启动，检查此次运行netstat -a并检查Postgres是否在等待5432端口上的连接
用户名/密码错误 - 尝试使用控制台或PG管理员使用这些凭据连接到Postgres
可能会发生，特别是如果Postgres在Linux机器上，由于安全原因，它不允许TCP / IP连接。你需要启用它。在网上搜索“启用远程Postgres连接”或“启用Postgres tcp / ip连接”，有大量的信息。
答案 1 :(得分：0)
您需要在postgres目录中配置postgresql.conf和pg_hba.conf文件。
打开 postgresql.conf 文件并替换行
listen_addresses = 'localhost'
使用
listen_addresses = '*'
如果#的jsut删除以“ listen_addresses”开头，则会使它们成为注释行。现在重新启动postgresql服务器。
pg_hba.conf
host all all 0.0.0.0/0 md5
将此行添加到pg_hba.conf的末尾。
md5表示密码是连接所必需的，如果您不希望将任何密码更改为trust，则表示无条件接受连接。
0.0.0.0/0表示您还可以根据需要更改每个IP地址。