PostgreSQL pg_hba.conf to access policy configuration file, located by default in / var / lib / pgsql / 10 / data / directory (PostgreSQL10).
The profile has five parameters, namely: TYPE (host type), DATABASE (database name), the USER (user name), ADDRESS (IP address and mask), the METHOD (encryption method)
TYPE, there are four values
local: using Unix-hardliners domainsocket Host: using the TCP / the IP connection, the SSL may be, may not hostssl: SSL must be of hostnossl: must be non-SSL is
DATABASE：
Database name, can be "all", "sameuser", "samerole", "replication". all means all, but does not include replication. With multiple databases "," separated.
USER：
User name, which can be "all", means all, you can also specify a user. Multiple users with "," separated. Like DATABASE and can also be placed in the configuration file, the file name prefixed with @
ADDRESS：
It can be a host name, or by the IP address and CIDR mask composition. Mask may be an integer between 0-32 (IPv4) or 0-128 (IPv6), 32 represents a subnet mask of the subnet mask is represented 255.255.255.255,24 255.255.255.0. Host names. "" Beginning. samehost can match all hosts, samenet can match all hosts within the same mask.
Example: 192.168.10.122/32 represent a single host, 192.168.10.0 / 24 subnet 192.168.0.1 ~ 192.168.0.255 represents all hosts, 0.0.0.0 / 0 indicates all hosts.
METHOD：
Password encryption policy, password represents the password is sent in plain text, md5 and scram-sha-256 will be encrypted in a corresponding manner sending the password again.
