For TOSS systems using Domain Name Servers (DNS) resolution, at least two name servers must be configured.
An XCCDF Rule
Description
To provide availability for name resolution services, multiple redundant name servers are mandated. A failure in name resolution could lead to the failure of security functions requiring name resolution, which may include time synchronization, centralized authentication, and remote system logging.
- ID
- SV-252935r991589_rule
- Version
- TOSS-04-010330
- Severity
- Medium
- References
- Updated
Remediation Templates
A Manual Procedure
Configure the operating system to use two or more name servers for DNS resolution.
By default, "NetworkManager" on TOSS dynamically updates the /etc/resolv.conf file with the DNS settings from active "NetworkManager" connection profiles. However, this feature can be disabled to allow manual configurations.
If manually configuring DNS, edit the "/etc/resolv.conf" file to uncomment or add the two or more "nameserver" option lines with the IP address of local authoritative name servers. If local host resolution is being performed, the "/etc/resolv.conf" file must be empty. An empty "/etc/resolv.conf" file can be created as follows:
$ sudo echo -n > /etc/resolv.conf