Explanation
If a server has two arrays on the failed server: a two-drive RAID 0 set for the OS, and an eight-drive RAID 10 set for data, then the most likely failure scenario that caused the server to crash and not boot is that a drive failed in the OS array. RAID 0 is a RAID configuration that stripes data across two or more drives without parity or redundancy. RAID 0 offers high performance but no fault tolerance. If one drive fails in RAID 0, all data is lost and the system cannot boot. RAID 10 is a RAID configuration that combines disk mirroring and disk striping with parity. RAID 10 offers high performance and fault tolerance. RAID 10 can tolerate up to one drive failure per mirrored pair without losing data or functionality.References:https://www.technewstoday.com/what-is-a-raid-0/
https://www.technewstoday.com/what-is-a-raid-10/

Explanation
The cluster feature that will allow Ann to complete her task is failback. A cluster is a group of servers that work together to provide high availability, scalability, and load balancing for applications or services. A cluster can have different nodes or members that have different roles or states. An active node is a node that is currently running an application or service and serving requests from clients. A passive node is a node that is on standby and ready to take over if the active node fails. A failover is a process of switching from a failed or unavailable node to another node in a cluster. A failback is a process of switching back from a failover node to the original node after it becomes available again. Failback can be automatic or manual depending on the cluster configuration.

Explanation
A host firewall is a software that controls the incoming and outgoing network traffic on a server based on predefined rules and filters. It can block or allow certain ports, protocols, or addresses that are used for communication with other servers or devices. If a server is unable to connect to another server after applying a patch, it is possible that the patch changed or added a firewall rule that prevents the connection. The administrator should check the host firewall rule and modify it if necessary to restore connectivity. Verified References: [Host firewall], [Network connection]

A link aggregation group (LAG) is a technique that combines multiple physical network interfaces into a single logical interface. This allows for the distribution of traffic across all the interfaces in the group, increasing bandwidth and redundancy. A LAG can use different modes to balance the load, such as address hashing, dynamic, or most recently used algorithm.
References: CompTIA Server+ Study Guide, Chapter 6: Networking, page 239.