无法从 Docker 连接到 postgres

Question

我有一个 docker 图像，其中我有一个主节点和两个从节点组成的 hadoop 集群。在这个集群上，我有 HBase。

我正在尝试使用 scoop 将安装在本地计算机上的 postgres 数据库迁移到 Docker 图像上的 HBase 数据库。

对于 postgres，这是我的 postgresql.conf 配置文件：

#------------------------------------------------------------------------------
# CONNECTIONS AND AUTHENTICATION
#------------------------------------------------------------------------------

# - Connection Settings -

listen_addresses = '*'          # what IP address(es) to listen on;
                                        # comma-separated list of addresses;
                                        # defaults to 'localhost'; use '*' for all
                                        # (change requires restart) port = 5432                             # (change requires restart)
max_connections = 100                   # (change requires restart)
#superuser_reserved_connections = 3     # (change requires restart) unix_socket_directories = '/var/run/postgresql' # comma-separated list
of directories
                                        # (change requires restart)
#unix_socket_group = ''                 # (change requires restart)
#unix_socket_permissions = 0777         # begin with 0 to use octal notation
                                        # (change requires restart)
#bonjour = off                          # advertise server via Bonjour
                                        # (change requires restart)
#bonjour_name = ''                      # defaults to the computer name


# - Security and Authentication -

#authentication_timeout = 1min          # 1s-600s ssl = on
#ssl_ciphers = 'HIGH:MEDIUM:+3DES:!aNULL' # allowed SSL ciphers
#ssl_prefer_server_ciphers = on
#ssl_ecdh_curve = 'prime256v1'
#ssl_dh_params_file = '' ssl_cert_file = '/etc/ssl/certs/ssl-cert-snakeoil.pem' ssl_key_file =
'/etc/ssl/private/ssl-cert-snakeoil.key'
#ssl_ca_file = ''
#ssl_crl_file = ''
#password_encryption = md5              # md5 or scram-sha-256
#db_user_namespace = off
#row_security = on

# GSSAPI using Kerberos
#krb_server_keyfile = ''
#krb_caseins_users = off

# - TCP Keepalives -
# see "man 7 tcp" for details

#tcp_keepalives_idle = 0                # TCP_KEEPIDLE, in seconds;
                                        # 0 selects the system default
#tcp_keepalives_interval = 0            # TCP_KEEPINTVL, in seconds;
                                        # 0 selects the system default
#tcp_keepalives_count = 0               # TCP_KEEPCNT;
                                        # 0 selects the system default

这也是 pg_hba.conf 文件的内容：

# Database administrative login by Unix domain socket local   all             postgres                                peer

# TYPE  DATABASE        USER            ADDRESS                 METHOD

# "local" is for Unix domain socket connections only local   all             all                                     trust
# IPv4 local connections: host    all             all             127.0.0.1/32            trust
# IPv6 local connections: host    all             all             ::1/128                 trust
# Allow replication connections from localhost, by a user with the
# replication privilege. 
local   replication     all                              trust 

host    replication     all             127.0.0.1/32     trust      
host    replication     all             ::1/128

我的问题是当我尝试使用 scoop 使用此命令从 docker 图像连接到 postgres 时：

sqoop import --connect jdbc:postgresql://localhost:5432/mimic --username postgres --password 0000 --table admission_ids --hbase-table mimic --column-family admission_ids --hbase-row-key id -m 1

我刚遇到这个问题：

Check that the hostname and port are correct and that the postmaster
is accepting TCP/IP connections. org.postgresql.util.PSQLException:
Connection refused. Check that the hostname and port are correct and
that the postmaster is accepting TCP/IP connections.

经过搜索，我才明白 docker 是这个问题的根源，为了确认这一点，我只是在第一时间尝试从我的本地计算机使用 tenlnet 连接到 postgres，这是结果：

telnet localhost 5432
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.

第二次来自docker：

telnet localhost 5432
Trying 127.0.0.1...
Trying ::1...
telnet: Unable to connect to remote host: Cannot assign requested address

我的 docker 图像被命名为 spark-hadoop。

我尝试运行此命令但始终无法正常工作：

docker run -d --name bridgeToHadoop --publish=127.0.0.1:5432:5432 -p 172.18.0.2:5432:5432 spark-hadoop

Answer 1

主机上的 Postgresql 运行，您正尝试从 docker 容器连接它。执行此操作时，主机不应在连接字符串中为 localhost。这里localhost的意思是docker容器。

用IP地址替换localhost，应该是下面的

sqoop import --connect jdbc:postgresql://host-pi-addr:5432/mimic --username postgres --password 0000 --table admission_ids --hbase-table mimic --column-family admission_ids --hbase-row-key id -m 1

Answer 2

Docker 为容器网络使用默认的 172.17.0.0/16 子网 IP 范围。您需要允许 non-local 个连接，因为您的容器网络不再被视为相对于 postgres 服务器的本地网络。要允许适当范围内的外部连接，请将以下内容添加到 pg_hba.conf（对数据库、用户和方法进行适当的选择）。

#TYPE   DATABASE   USER   ADDRESS          METHOD
host    all        all    172.17.0.0/16    scram-sha-256`

此外，默认情况下 postgres 服务器仅侦听 localhost，因此您还需要通过将以下内容添加到 postgresql.conf.

来告诉 postgres 侦听其他 IP 地址

listen_addresses = '*'

无法从 Docker 连接到 postgres

can not connect to postgres from Docker

postgresql

hadoop

hbase

docker