CompTIA SK0-005 - CompTIA Server+ Certification Exam

The administrator should use a subnet mask of 255.255.255.0 for this setup. A subnet mask is a binary number that defines how many bits of an IP address areused for the network portion and how many bits are used for the host portion. The network portion identifies the specific network that the IP address belongs to, while the host portion identifies the specific device within that network. The subnet mask is usually written in dotted decimal notation, where each octet represents eight bits of the binary number. A 1 in the binary number means that the corresponding bit in the IP address is part of the network portion, while a 0 means that it is part of the host portion. For example, a subnet mask of 255.255.255.0 means that the first 24 bits (three octets) of the IP address are used for the network portion and the last 8 bits (one octet) are used for the host portion. This subnet mask allows up to 254 hosts per network (2^8 - 2). In this case, the IP address of 10.20.10.15 and the default gateway of 10.20.10.254 belong to the same network of 10.20.10.0/24 (where /24 indicates the number of bits used for the network portion), which can be defined by using a subnet mask of 255.255.255.0.

RTO (Recovery Time Objective) is a measure of how much downtime an organization can tolerate during an unplanned outage. It is the maximum time allowed for restoring normal operations after a disaster. RTO is one of the key metrics for disaster recovery planning and testing. SLA (Service Level Agreement) is a contract that defines the expected level of service and performance between a provider and a customer. BIA (Business Impact Analysis) is a process that identifies and evaluates the potential effects of a disaster on critical business functions and processes. MTTR (Mean Time To Repair) is a measure of how long it takes to fix a failed component or system. References: https://parachute.cloud/rto-vs-rpo/ https://www.techopedia.com/definition/13622/service-level-agreement-sla https://www.techopedia.com/definition/1032/business-impact-analysis-biahttps://www.techopedia.com/definition/8239/mean-time-to-repair-mttr

A warm site is a type of disaster recovery site that has a target storage array that receives replication traffic and servers that are only powered on in the event of a disaster. A warm site is a compromise between a hot site and a cold site. A warm site has some equipment and data ready, but requires some configuration and restoration before resuming operations. A warm site is usually located in a different geographic area than the primary site and has redundant power, cooling, network, and security systems. A warm site is suitable for organizations that can tolerate some downtime and data loss in case of a disaster. A cloud site is a type of disaster recovery site that uses cloud-based resources and platforms to store backups and restore data and applications after a disaster. A cold site is a type of disaster recovery site that has only basic infrastructure and space available, but requires significant setup and installation before resuming operations. A hot site is a type of disaster recovery site that has all the equipment and data ready to resume operations as soon as possible after a disaster. References: https://www.techopedia.com/definition/11172/hot-site https://www.techopedia.com/definition/11173/warm-site https://www.techopedia.com/definition/11174/cold-sitehttps://www.techopedia.com/definition/29836/cloud-recovery

The backup type that only records changes to the data blocks on a virtual machine is snapshot. A snapshot is a point-in-time copy of a virtual machine (VM) that captures the state and data of the VM at a specific moment. A snapshot can be created instantly and with minimal overhead, as it only stores the changes made to the VM after the snapshot was taken. A snapshot can be used to restore the VM to its previous state in case of data loss or corruption.

This is the best action to perform before applying patches to one of the hosts in a high availability cluster. A high availability cluster is a group of hosts thatact like a single system and provide continuous uptime. A high availability cluster is often used for load balancing, backup, and failover purposes. Failover is a process of transferring workloads from one host to another in case of a failure or maintenance. By failing over all VMs (Virtual Machines) from the host that needs to be patched to another host in the cluster, the technician can ensure that there is no downtime or data loss during the patching process. Disabling the heartbeat network is not a good action to perform, as this would disrupt the communication and synchronization between the hosts in the cluster. Fallback cluster services is not a valid term, but it may refer to restoring cluster services after a failover, which is not relevant before applying patches. Setting the cluster to active-active is not a good action to perform, as this would increase the load on both hosts and reduce redundancy. References: https://www.howtogeek.com/190014/virtualization-basics-understanding-techniques-and-fundamentals/https://www.howtogeek.com/428483/what-is-end-to-end-encryption-and-why-does-it-matter/

This is the most likely reason why the fans in that server are operating at full speed while the ambient temperature in the room is normal and the other servers in the rack are not experiencing this behavior. A fan failure is a situation where one or more fans in a server stop working or malfunction due to wear and tear, dust, or other factors. This can cause overheating and performance issues on the server. To prevent this, most servers have a fan redundancy feature that allows the other fans to increase their speed and airflow to compensate for the failed fan and maintain a safe temperature level. The server is not likely to be in the process of shutting down, as this would not cause the fans to run at high speeds. An incorrect fan size is not likely to be inserted into the server, as most fans are standardized and compatible with the server chassis and motherboard. The server is not likely to be utilizing more memory than the other servers, as this would not cause a significant increase in temperature or fan speed. References: https://www.howtogeek.com/303282/how-to-manage-your-pcs-fans-for-optimal-airflow-and-cooling/https://www.howtogeek.com/174288/how-to-tell-if-your-computer-is-overheating-and-what-to-do-about-it/

The administrator should use the command chmod 754 /home/Ann to resolve the issue without granting unnecessary permissions. The chmod command is used to change the permissions of files and directories on a Linux server. The permissions are represented by three numbers, each ranging from 0 to 7, that correspond to the read ®, write (w), and execute (x) permissions for the owner, group, and others respectively. The numbers are calculated by adding up the values of each permission: r = 4, w = 2, x = 1. For example, 7 means rwx (4 + 2 + 1), 6 means rw- (4 + 2), 5 means r-x (4 + 1), etc. In this case, Ann’s home directory has the permissions dr-xr-xr–, which means that only the owner (d) can read ® and execute (x) the directory, and the group and others can only read ® and execute (x) but not write (w) to it. This prevents Ann from saving files to her home directory. To fix this issue, the administrator should grant write permission to the owner by using chmod 754 /home/Ann, which means that the owner can read ®, write (w), and execute (x) the directory, the group can read ® and execute (x) but not write (w) to it, and others can only read ® but not write (w) or execute (x) it. This way, Ann can save files to her home directory without giving unnecessary permissions to others.

RAID 1 (mirroring) is a RAID configuration that should be used to provide redundancy for the OS on a server that has two hard drives on which to install the OS. RAID 1 (mirroring) is a configuration that duplicates data across two or more drives. It provides fault tolerance and improves read performance, but reduces storage capacity by half. If one drive fails in RAID 1, the other drive can continue to operate without data loss or system downtime. RAID 0 (striping) is a configuration that splits data across two or more drives without parity or redundancy. It improves performance but offers no fault tolerance. If one drive fails in RAID 0, all data is lost and the system cannot boot. RAID 5 (striping with parity) is a configuration that stripes data across three or more drives with parity information. It provides fault tolerance and improves performance, but reduces storage capacity by one drive’s worth of space. RAID 5 can tolerate one drive failure without data loss, but not two ormore. RAID 6 (striping with double parity) is a configuration that stripes data across four or more drives with double parity information. It provides fault tolerance and improves performance, but reduces storage capacity by two drives’ worth of space. RAID 6 can tolerate two drive failures without data loss, but not three or more.References:https://www.howtogeek.com/199068/how-to-upgrade-your-existing-hard-drive-in-under-an-hour/

The administrator should only allow secure traffic and DNS inquiries on the server, which means that only ports 22, 53, and 443 should be open. Port 22 is used for SSH (Secure Shell), which is a protocol that allows secure remote login and command execution over a network connection using a command-line interface (CLI). Port 53 is used for DNS (Domain Name System), which is a service that translates domain names into IP addresses and vice versa. Port 443 is used for HTTPS (Hypertext Transfer Protocol Secure), which is a secure version of HTTP that encrypts the data exchanged between a web browser and a web server.

An IDRAC (Integrated Dell Remote Access Controller) is a tool that can be used to command a remote shutdown of a physical Linux server. An IDRAC is a hardware device that provides out-of-band management for Dell servers. It allows the technician to access the server’s console, power cycle, reboot, or shut down the server remotely using a web interface or a command-line interface. An IDRAC does not depend on the operating system or network connectivity of the server. A virtual serial console is a tool that can be used to access a remote virtual machine’s console using a serial port connection. A KVM (Keyboard, Video, Mouse) switch is a device that allows the technician to switch between different computer sources using the same keyboard, monitor, and mouse. A crash cart is a mobile unit that contains a keyboard, monitor, mouse, and other tools that can be connected to a physical server for troubleshooting purposes. References: https://www.dell.com/support/kbdoc/en-us/000131486/understanding-the-idrac https://www.howtogeek.com/799968/what-is-a-kvm-switch/https://www.techopedia.com/definition/1032/business-impact-analysis-bia