如何从管理员访问 postgres数据库？
我已更改用户的密码postgres：
$ sudo -u postgres psql
$ postgres=# alter user postgres password 'secret';
结果：
ALTER ROLE
但是我仍然在管理员上收到此错误：
Unable to connect to PostgreSQL server: FATAL: Peer authentication failed for user "postgres"
任何想法为什么？
我有这两个用户：
postgres=# \du
List of roles
Role name | Attributes | Member of
-----------+------------------------------------------------------------+-----------
postgres | Superuser, Create role, Create DB, Replication, Bypass RLS | {}
root | Superuser, Create role, Create DB | {}
root但是当我使用以下命令创建用户时，我没有为用户设置密码：
sudo -u postgres createuser --interactive
输出（为什么不要求输入密码？？）：
Enter name of role to add: root
Shall the new role be a superuser? (y/n) y
但我仍然收到管理员错误：
Unable to connect to PostgreSQL server: FATAL: Peer authentication failed for user "root"
编辑：
这是我的一些pg_hba.conf
sudo nano /etc/postgresql/9.5/main/pg_hba.conf
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all peer
# IPv4 local connections:
host all all 127.0.0.1/32 md5
# IPv6 local connections:
host all all ::1/128 md5
# Allow replication connections from localhost, by a user with the
# replication privilege.
#local replication postgres peer
#host replication postgres 127.0.0.1/32 md5
#host replication postgres ::1/128 md5
我peer改为ident：
# Database administrative login by Unix domain socket
local all postgres ident
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all ident
# IPv4 local connections:
host all all 127.0.0.1/32 md5
# IPv6 local connections:
host all all ::1/128 md5
# Allow replication connections from localhost, by a user with the
# replication privilege.
#local replication postgres peer
#host replication postgres 127.0.0.1/32 md5
#host replication postgres ::1/128 md5
然后重新启动了我的机器。但仍然没有运气。