COA Implementation & Configuration 3 — Questions and Answers
Question 1: Which configuration file controls the Nova compute service on a compute node?
- /etc/nova/nova.conf (Correct answer)
- /etc/nova/compute.conf
- /etc/openstack/nova-compute.ini
- /etc/nova/hypervisor.conf
Correct answer: /etc/nova/nova.conf
nova.conf is the primary configuration file for all Nova services including nova-compute on each compute node.
Question 2: When configuring Keystone with Fernet tokens, which command initializes the Fernet key repository?
- keystone-manage fernet_setup --keystone-user keystone --keystone-group keystone (Correct answer)
- keystone-manage token_setup --type fernet
- openstack token fernet init --user keystone
- keystone-manage credential_setup --fernet
Correct answer: keystone-manage fernet_setup --keystone-user keystone --keystone-group keystone
keystone-manage fernet_setup initializes the Fernet key repository and sets the correct ownership for the key directory.
Question 3: Which Glance image property signals Nova to use a config drive when booting an instance?
- img_config_drive=mandatory (Correct answer)
- hw_config_drive=true
- disk_config=AUTO
- block_device_mapping_v2=config_drive
Correct answer: img_config_drive=mandatory
Setting img_config_drive=mandatory in the Glance image metadata forces Nova to attach a config drive for every instance created from that image.
Question 4: In an OpenStack deployment, what is the function of the 'placement' service?
- Tracks resource provider inventories and allocations to support Nova scheduling decisions (Correct answer)
- Manages physical rack placement and server asset inventory
- Provides IP address allocation for Neutron DHCP agents
- Handles block storage placement across Cinder backends
Correct answer: Tracks resource provider inventories and allocations to support Nova scheduling decisions
The Placement API (originally part of Nova) tracks resource inventories like vCPU, RAM, and disk across compute nodes to help the scheduler make placement decisions.
Question 5: Which OpenStack CLI command lists all available flavors?
- openstack flavor list (Correct answer)
- nova flavor-list
- openstack compute flavor show
- openstack server flavor list
Correct answer: openstack flavor list
The 'openstack flavor list' command displays all available instance flavors defined in Nova.
Question 6: What does the 'allowed_address_pairs' Neutron port attribute enable?
- Permits traffic from additional IP/MAC addresses beyond the port's assigned address, enabling virtual IPs and failover (Correct answer)
- Restricts the port to only communicate with a specific list of IP addresses
- Configures port-level QoS policies for allowed bandwidth
- Enables MAC spoofing detection on the virtual switch
Correct answer: Permits traffic from additional IP/MAC addresses beyond the port's assigned address, enabling virtual IPs and failover
allowed_address_pairs lets a port accept traffic destined for additional IP/MAC combinations, which is needed for VRRP, keepalived, or other HA virtual IP setups.
Question 7: Which command creates a Neutron security group rule to allow inbound SSH (port 22) from any source?
- openstack security group rule create --proto tcp --dst-port 22 --remote-ip 0.0.0.0/0 <group> (Correct answer)
- openstack security group add rule --port 22 --direction ingress <group>
- neutron security-group-rule-create --protocol tcp --port-range-min 22 <group>
- openstack firewall rule create --protocol tcp --dport 22 <group>
Correct answer: openstack security group rule create --proto tcp --dst-port 22 --remote-ip 0.0.0.0/0 <group>
The correct unified CLI syntax specifies the protocol, destination port, remote IP CIDR, and the target security group name or ID.
COA Implementation & Configuration 3
Which configuration file controls the Nova compute service on a compute node?