RHCSA Firewalld and Network Configuration Flashcards

Which command shows all available firewalld zones?

Answer: firewall-cmd --get-zones

--get-zones prints a space-separated list of all zones defined on the system.

A developer needs traffic from 10.0.0.0/8 to always be treated as 'trusted'. What is the best approach?

Answer: firewall-cmd --zone=trusted --add-source=10.0.0.0/8 --permanent

Adding a source CIDR to the trusted zone routes all packets from that network through the trusted zone policy.

Which nmcli property sets the DNS server for a connection?

Answer: ipv4.dns

The ipv4.dns property in NetworkManager holds one or more DNS server addresses for a connection.

What does 'firewall-cmd --zone=public --query-service=https' return?

Answer: yes or no indicating if the https service is currently enabled in the public zone

--query-service returns 'yes' if the service is active in the zone at runtime, 'no' otherwise.

To configure NetworkManager to use a connection only for specific traffic and not set it as the default route, which setting is used?

Answer: ipv4.never-default yes

Setting ipv4.never-default to yes prevents NetworkManager from using that connection as the default gateway.

Which command removes the 'ftp' service from the 'public' zone permanently?

Answer: firewall-cmd --zone=public --remove-service=ftp --permanent

--remove-service removes a predefined service from the specified zone when combined with --permanent.

What is the purpose of 'firewall-cmd --runtime-to-permanent'?

Answer: Copies all current runtime rules to the permanent configuration

--runtime-to-permanent saves everything currently active at runtime into the permanent on-disk configuration.