CentOS 7, PostgreSQL failed to read permission data directory in mounted partition I've a problem with start PostgreSQL 9.4 on Centos 7 Server. Because the partition /var/lib/pgsql/9.4/data/ (which contains PostgreSQL data) is full so I want to change to another partition.

/dev/sdb1               154685904  322500 146482752   1% /run/media/root/Data


I've used this command to copy all the old data to new data folder:

cp -a /var/lib/pgsql/9.4/data/ /run/media/root/Data/pgsql_data


Then I changed the directory to new data directory in postgresql.conf (/var/lib/pgsql/9.4/data)

data_directory = '/run/media/root/Data/pgsql_data/'     # use data in another directory


And then I try to restart PostgreSQL, here are errors:

postgresql-9.4.service - PostgreSQL 9.4 database server    
Loaded: loaded (/usr/lib/systemd/system/postgresql-9.4.service; enabled)    
Active: failed (Result: exit-code) since Wed 2015-03-11 09:17:21 ICT; 4s ago   
Process: 54975 ExecStop=/usr/pgsql-9.4/bin/pg_ctl stop -D ${PGDATA} -s -m fast (code=exited, status=0/SUCCESS)   
Process: 56133 ExecStart=/usr/pgsql-9.4/bin/pg_ctl start -D ${PGDATA} -s -w -t 300 (code=exited, status=1/FAILURE)   
Process: 56127 ExecStartPre=/usr/pgsql-9.4/bin/postgresql94-check-db-dir ${PGDATA} (code=exited, status=0/SUCCESS)  
Main PID: 54580 (code=exited, status=0/SUCCESS)

Mar 11 09:17:16 localhost.localdomain pg_ctl[56133]: LOG:  skipping missing configuration file "/run/media/root/Data/pgsql_data/postgresql.auto.conf" 
Mar 11 09:17:16 localhost.localdomain pg_ctl[56133]: &lt; 2015-03-10 22:17:16.187 EDT FATAL:  could not read permissions of directory "/run/media/root/Data/pgsql_data": Permission denied 
Mar 11 09:17:21 localhost.localdomain pg_ctl[56133]: pg_ctl: could not start server 
Mar 11 09:17:21 localhost.localdomain pg_ctl[56133]: Examine the log output. 
Mar 11 09:17:21 localhost.localdomain systemd[1]: postgresql-9.4.service: control process exited, code=exited status=1 
Mar 11 09:17:21 localhost.localdomain systemd[1]: Failed to start PostgreSQL 9.4 database server. 
Mar 11 09:17:21 localhost.localdomain systemd[1]: Unit postgresql-9.4.service entered failed state.


Please help!
You are obviously missing some permissions in the new location. 

I have tried to reproduce your error on my local test cluster.  I could get several different errors along the way but never the one you got.  However, here are the permissions you need on your directories to run the cluster:


the data_directory (in your case, pgsql_data) must be owned by postgres (the group seems making no difference)
it must have 0700 as permissions (no group and world level permissions are allowed)
all directories under this need 07XX, where XX refers to the group and world permissions - I haven't found any restrictions to these (but obviously didn't try all possibilities)


Based on my experiments, these should be enough for starting PostgreSQL.