To access some resource information, the agent must have root access to the resource itself. However, for security, many administrators do not want to run the agent process as root.
On Red Hat Enterprise Linux, it is possible to grant access to the agent to specific resources while running the agent as a non-root user. This is done by setting local access control rules to the local directories or files for the resource.
This example sets ACLs for a PostgreSQL database; the directories and files to specify in the setfacl command will vary depending on the resource type.
Log into the system as root.
Make sure that the acl package is installed on the system.
# rpm -q acl
acl option must be applied to the filesystem. This can be done by editing the
/etc/fstab file or using tune2fs. For example:
# vim /etc/fstab
LABEL=/ / ext3 defaults
,acl 1 1
Then re-mount the filesystem.
# mount -o remount /
Optionally, create a system user to use for the agent.
For PostgreSQL, the agent needs to be able to access the
postgresql.conf file. Open the PostgreSQL directory:
# cd /var/lib/pgsql
Grant read and write access to the
postgresql.conf file to the agent user. For example:
# setfacl -m u:jbosson-agent:rw $PGDATA/postgresql.conf
Then, grant access to the
data/ directory to the agent user. For example:
# setfacl -m u:jbosson-agent:x $PGDATA
Check that the new ACLs were added properly using the getfacl command:
# getfacl .
# file: .
# owner: postgres
# group: postgres