Red Hat Linux 6.2: The Official Red Hat High Availability Server Installation Guide Prev Next Chapter 6. Post-Installation Security Overview After installing Red Hat High Availability Server 1.0, you will need to consider the security-related aspects of deploying a highly-available server environment. As a first step in this process, the installation program makes the following changes to the network environment over that used in a standard Red Hat Linux 6.2 installation. The /etc/hosts.deny File Set to Deny All Access The tcp_wrappers utility is used to control access to many network services. Therefore, the default /etc/hosts.deny is set to ALL: ALL (meaning that all remote hosts are denied access to all services). In addition, /etc/hosts.allow contains no active entries, meaning that any service run out of inetd would fail to start and a message to that effect is recorded in the system message logs. You should edit /etc/hosts.allow to include only trusted systems that should be allowed access. The following man pages are part of tcp_wrappers: hosts.allow hosts.deny.5.gz hosts_access (Section 3) hosts_access (Section 5) hosts_options tcpd tcpdchk tcpdmatch Prev Home Next Red Hat High Availability Server — Technology Overview Up System Logging Set to 60 Days