无法使用PgAdmin在Amazon EC2实例上远程连接到PostgreSQL

Question

我有一个运行的微型免费层RHEL 6实例,并使用yum说明安装了postgresql 9.2:http: //yum.pgrpms.org/howtoyum.php

我可以使用此服务器在本地连接到PG服务器:

03:46:20 root@xxx[~]$ psql -hlocalhost -p5432 -Upostgres

但是,我从来没有成功地连接到盒子外面.错误消息如下所示:

12:11:56 saladinxu@GoodOldMBP[~]$ psql -h ec2-xxx.ap-southeast-1.compute.amazonaws.com -p5432 -Upostgres
    psql: could not connect to server: Connection refused
    Is the server running on host "ec2-54-251-188-3.ap-southeast-1.compute.amazonaws.com" (54.251.188.3) and accepting TCP/IP connections on port 5432?

我尝试了很多不同的方法.以下是我的配置文件现在的样子:

/var/lib/pgsql/9.2/data/postgresql.conf:

...

# - Connection Settings -

listen_addresses = '*'      # what IP address(es) to listen on;
                # comma-separated list of addresses;
                # defaults to 'localhost'; use '*' for all
port = 5432             # (change requires restart)
max_connections = 100           # (change requires restart)
...

/var/lib/pgsql/9.2/data/pg_hba.conf:

# TYPE  DATABASE        USER            ADDRESS                 METHOD
host    all             pgadmin         0.0.0.0/24              trust
host    all             all             [my ip]/24         md5
# "local" is for Unix domain socket connections only
local   all             all                                     peer
# IPv4 local connections:
host    all             all             127.0.0.1/32            ident
# IPv6 local connections:
host    all             all             ::1/128                 ident

我试图将上面的地址设为0.0.0.0/0但是id不起作用.

每次我做出改变,我都会通过运行来重新启动

service postgresql-9.2 restart

在这个EC2实例的安全组中,我可以看到这个规则:

TCP
Port (Service)  Source  Action
22 (SSH)    0.0.0.0/0   Delete
80 (HTTP)   0.0.0.0/0   Delete
5432    0.0.0.0/0   Delete

netstat命令显示端口已打开:

04:07:46 root@ip-172-31-26-139[~]$ netstat -na|grep 5432
tcp        0      0 0.0.0.0:5432                0.0.0.0:*                   LISTEN      
tcp        0      0 :::5432                     :::*                        LISTEN      
unix  2      [ ACC ]     STREAM     LISTENING     14365  /tmp/.s.PGSQL.5432

回答bma的问题:

如果我在本地服务器上运行nmap命令,似乎建议通过内部DNS它将转到另一个5432打开的主机:

10:16:05 root@ip-172-31-26-139[~]$ nmap -Pnv -p 5432 ec2-54-251-188-3.ap-southeast-1.compute.amazonaws.com

Starting Nmap 5.51 ( http://nmap.org ) at 2013-07-22 10:16 EDT
Nmap scan report for ec2-54-251-188-3.ap-southeast-1.compute.amazonaws.com (172.31.26.139)
Host is up (0.00012s latency).
rDNS record for 172.31.26.139: ip-172-31-26-139.ap-southeast-1.compute.internal
PORT     STATE SERVICE
5432/tcp open  postgresql

Nmap done: 1 IP address (1 host up) scanned in 0.07 seconds

并且iptables命令提供以下输出

10:16:14 root@ip-172-31-26-139[~]$ iptables -nvL
Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target     prot opt in     out     source               destination         
25776   14M ACCEPT     all  --  *      *       0.0.0.0/0            0.0.0.0/0           state RELATED,ESTABLISHED 
0     0 ACCEPT     icmp --  *      *       0.0.0.0/0            0.0.0.0/0           
45  1801 ACCEPT     all  --  lo     *       0.0.0.0/0            0.0.0.0/0           
251 15008 ACCEPT     tcp  --  *      *       0.0.0.0/0            0.0.0.0/0           state NEW tcp dpt:22 
35  2016 REJECT     all  --  *      *       0.0.0.0/0            0.0.0.0/0           reject-with icmp-host-prohibited 

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target     prot opt in     out     source               destination         
0     0 REJECT     all  --  *      *       0.0.0.0/0            0.0.0.0/0           reject-with icmp-host-prohibited 

Chain OUTPUT (policy ACCEPT 21695 packets, 5138K bytes)
pkts bytes target     prot opt in     out     source               destination  

[根据bma的建议加入后编辑]

新增后,iptables看起来像这样:

11:57:20 root@ip-172-31-26-139[~]$ iptables -nvL
Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
 pkts bytes target     prot opt in     out     source               destination         
26516   14M ACCEPT     all  --  *      *       0.0.0.0/0            0.0.0.0/0           state RELATED,ESTABLISHED 
0     0 ACCEPT     icmp --  *      *       0.0.0.0/0            0.0.0.0/0           
47  1885 ACCEPT     all  --  lo     *       0.0.0.0/0            0.0.0.0/0           
255 15236 ACCEPT     tcp  --  *      *       0.0.0.0/0            0.0.0.0/0           state NEW tcp dpt:22 
38  2208 REJECT     all  --  *      *       0.0.0.0/0            0.0.0.0/0           reject-with icmp-host-prohibited 
0     0 ACCEPT     tcp  --  *      *       [my ip]         54.251.188.3        tcp spts:1024:65535 dpt:5432 state NEW,ESTABLISHED 
0     0 ACCEPT     tcp  --  *      *       0.0.0.0/0            54.251.188.3        tcp spt:5432 dpts:1024:65535 state ESTABLISHED 

Chain FORWARD (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target     prot opt in     out     source               destination         
0     0 REJECT     all  --  *      *       0.0.0.0/0            0.0.0.0/0           reject-with icmp-host-prohibited 

Chain OUTPUT (policy ACCEPT 5 packets, 1124 bytes)
pkts bytes target     prot opt in     out     source               destination         
0     0 ACCEPT     tcp  --  *      *       54.251.188.3         [my ip]        tcp spt:5432 dpts:1024:65535 state ESTABLISHED 
0     0 ACCEPT     tcp  --  *      *       54.251.188.3         0.0.0.0/0           tcp spts:1024:65535 dpt:5432 state NEW,ESTABLISHED 

但我仍然无法连接(相同的错误).这里可能缺少什么？

Answer 1

我找到了解决这个问题的方法.需要做两件事.

1. 使用文本编辑器修改pg_hba.conf.找到该行:

   host all all 127.0.0.1/0 md5.

   紧接其下方,添加以下新行:

   host all all 0.0.0.0/0 md5

2. 编辑PostgreSQL postgresql.conf文件:

   使用文本编辑器修改postgresql.conf.

   找到以...开头的行#listen_addresses = 'localhost'.

   通过删除#,取消注释该行,并更改'localhost'为'*'.

   该行现在应该如下所示:

   listen_addresses = '*' # what IP address(es) to listen on;.

现在只需重新启动postgres服务即可连接

Answer 2

您的防火墙是否阻止端口 5432？快速 nmap 显示它正在被过滤。

nmap -Pnv -p 5432 ec2-54-251-188-3.ap-southeast-1.compute.amazonaws.com

Starting Nmap 6.00 ( http://nmap.org ) at 2013-07-21 11:05 PDT
Nmap scan report for ec2-54-251-188-3.ap-southeast-1.compute.amazonaws.com (54.251.188.3)
Host is up (0.19s latency).
PORT     STATE    SERVICE
5432/tcp filtered postgresql

EC2 上的 iptables 显示端口 5432 是什么？

iptables -nvL

[OP添加更多细节后]

Netstat 显示它正在侦听，但防火墙输出看起来不像 5432 端口已打开（我承认我不是一个网络专家）。参考我之前安装的一些注释，您可能需要向您的 IP 打开 EC2 端口 5432。

要允许输入防火墙访问，请将 YOUR-REMOTE-IP 替换为您要连接的 IP：

iptables -A INPUT -p tcp -s YOUR-REMOTE-IP --sport 1024:65535 -d 54.251.188.3 --dport 5432 -m state --state NEW,ESTABLISHED -j ACCEPT
iptables -A OUTPUT -p tcp -s 54.251.188.3 --sport 5432 -d YOUR-REMOTE-IP --dport 1024:65535 -m state --state ESTABLISHED -j ACCEPT

--出站访问

iptables -A OUTPUT -p tcp -s 54.251.188.3 --sport 1024:65535 -d 0/0 --dport 5432 -m state --state NEW,ESTABLISHED -j ACCEPT
iptables -A INPUT -p tcp -s 0/0 --sport 5432 -d 54.251.188.3 --dport 1024:65535 -m state --state ESTABLISHED -j ACCEPT

iptables -nvL之后列出什么。你能连接吗？