- Domain 3.0: Network Implementation
- Quick Check Answer Key
- Answers and Explanations
This chapter is from the book
This chapter is from the book
This chapter is from the book
Answers and Explanations
Objective 3.1
Answer: A. Samba is a product that provides file and print services to Windows-based clients. Samba does not offer thin client services, web server services or Proxy server services.
Answer: C. A Windows NT server hard drive may be formatted as NTFS and/or FAT. NTFS offers a wider range of services, including enhanced network security. The number of hard drives has nothing to do with the file structures NTFS or FAT; both can use multiple drives. Server backups are a normal and expected networking task no matter what type of file structure is used. Although the server can be used as a workstation (not recommended) NTFS does not provide this functionality.
Answer: A. NDS is the NetWare Directory Service and is proprietary to Novell, although it’s based on the X.400 protocol. Windows NT and Windows 9x are Microsoft products. UNIX is nonproprietary.
Answer: C. The directory structure used with Novell NetWare is called NDS. FAT is a file system associated with DOS and NTFS is a file system associated with Windows NT. The root file structure is normally associated with UNIX/Linux.
Answer: A. IPX is a protocol associated with Novell NetWare. NetBEUI is associated with MS Windows and AppleTalk is associated with Mac OS networks. MS-DOS is not a network protocol.
Answer: B. A Windows NT server hard drive may be formatted as NTFS and/or FAT. NTFS offers a wider range of services, including enhanced network security. The number of hard drives has nothing to do with the file structures NTFS or FAT; both can use multiple drives. Server backups are a normal and expected networking task no matter what type of file structure is used. Although the server can be used as a workstation (not recommended) NTFS does not provide this functionality.
Answer: C. NTFS (New Technology File System) originated with the HPFS file system that Microsoft and IBM developed for the OS/2 operating system. It’s the recommended choice for Windows NT. NTFS is recommended over FAT because NTFS is the more secure of the two, and NTFS is not limited by the 2GB partition limit of FAT. NTFS also utilizes the disk space far more efficiently than FAT.
Answer: B. Partitions and volumes are managed by two types of file services: Novell Storage Services (NSS), which first became available on version 5.0, and NetWare File System (NFS), which is the file service used on earlier versions of NetWare but is also available on version 5.0 and later.
Answers: A, C. Microsoft is noted for client operating systems. Virtually all the Microsoft operating systems run on a NetWare network as well as on an NT/2000/XP network. Both Microsoft and Novell support implementations of UNIX, generally with the TCP/IP protocol suite.
Answer: D. The Novell directory structure begins with a root. A root is the primary object from which the tree is built.
Answer: A. The basis of the Novell directory and file organization scheme is the Novell Directory Service, or NDS.
Answer: B. The basis of the Novell directory and file organization scheme is the Novell Directory Service, or NDS. NDS is based on the ITU (formerly known as CCITT) standard X.500.
Answer: B. The UNIX operating system is portable. It is adaptable to different situations, particularly machine types and file structures.
Answer: C. In contrast, NT and NetWare use some proprietary protocols that may not be compatible across networks. For example, UNIX uses the globally implemented TCP/IP as its networking protocol. In contrast, both NT and NetWare use proprietary networking protocols, NetBEUI and IPX, respectively, which poses some challenges for interconnectivity of networks.
Answer: A. Windows NT and NetWare include a proprietary set of TCP/IP utilities. However, all commercial versions of UNIX ship with a complete package of TCP/IP.
Answer: D. Windows NT and NetWare support only 32-bit applications. Because UNIX’s 64-bit capability has far superior performance applications, such as graphics and mathematical computations, it is invariably preferred over either NT or NetWare for such applications.
Answer: D. In contrast, NT and NetWare use some proprietary protocols that may not be compatible across networks. For example, UNIX uses the globally implemented TCP/IP as its networking protocol. In contrast, both NT and NetWare use proprietary networking protocols, NetBEUI and IPX, respectively, which pose some challenges for interconnectivity of networks.
Answer: A. For networking, Linux includes a complete set of TCP/IP protocols.
Answer: B. In a server-based environment, up time is normally one of the primary objectives. Therefore, you should never test hop servers and workstations in a live environment if possible. You should install the upgrade on a test server for evaluation before loading it on a working network server.
Answer: C. A workgroup is a network of computers that can share access to each other’s resources. Each computer in the workgroup maintains a list of user accounts describing passwords and access rights.
Answer: A. Share-level security involves password-protecting each shared resource on a workstation. It’s typically associated with workgroup or peer-to-peer LANs, but can also be applied to server-based networks.
Answer: D. Once a group account has been set up, a user may be assigned to it. Essentially, groups are a tool that eases the management of user accounts. From an administrative perspective, they save time over setting security for each user (which is how it must be done with share-level access). The option to use group accounts is set at the workstation by specifying user-level access.
Answer: C. Folders are replicated from one server to another. The machine that copies the folder to another machine is referred to as the export server, while the machine that receives the copy is called the import server. Folder replication, in addition to copying a file, automatically updates the copy when changes are made to the original.
Answer: B. Folders are replicated from one server to another. The machine that copies the folder to another machine is referred to as the export server, while the machine that receives the copy is called the import server. Folder replication, in addition to copying a file, automatically updates the copy when changes are made to the original.
Answer: B, C. If the MAC is an older workstation, AppleTalk will need to be enabled. However, with newer MACs, TCP/IP will be sufficient for all the machines to communicate.
Answer: B. CSNW stands for Client Services for NetWare. It is used to connect NT clients to NetWare-based servers for access to file and print sharing.
Answer: C. A UNIX client would require an IP address, a correct subnet mask, and a HOSTS file. WINS is used to resolve Windows-based NetBIOS names, and the LMHOST file is used to map out IP addresses with their relevant NetBIOS-named computers.
Answer: C. The Domain Controller (DC) in a Windows Server 2003 environment is the server that clients log in to to receive their access rights to various resources throughout the domain. As a result, the Domain Controller has stored what resources are able to be accessed by what client.
Answer: B. The Active Directory is a hierarchical directory service.
Answer: D. Apple Keychain allows a user to store multiple logins and passwords on a single user login.
Answer: D. Appleshare is used to allow Mac clients to communicate with Windows-based servers using the Apple File protocol (AFP). 802.11A is a wireless protocol.
Answer: A. When a user in a Linux environment wants to authenticate using Kerberos, the request is processed and granted by a Kerberos Key Distribution Center.
Answer: B. Both Admin and Power users groups are able to share folders by default.
Answer: D. There is no difference between mobile users and remote users in the Novell environment.
Objective 3.2
Answer: D. If the card is PnP compatible you can configure the card using software configuration. You must connect using coaxial or UTP cabling with either a BNC or RJ-45 connector, respectively. You should connect the cable first before installing the client software.
Answer: B. When assigning individual user access, there are two terms to understand: rights and profiles. Rights refer to the authorized permission to perform specific actions on the network. Profiles are the configuration settings made for each user. For example, a profile may be created that places a user in a group. This group has been given certain rights to perform specific actions on the network.
Answer: A. DHCP must be running on the server before a client can receive a dynamic IP address from a server.
Answer: B. A share-level security model must be configured on each workstation in the network. Answer A, user-level security, is set up on a server. The administrator can manage all security accounts from a central location rather than visit each workstation each time a change must be made. The network operating system doesn’t directly determine the security model used on a network.
Answer: C. Share-level access applies password protection to the folder level to control, read, and change access.
Answer: B. User-level access applies to permissions assigned to a single user account or group account with similar needs to network resources.
Answer: A. User-level security is more secure and requires a user to provide a login ID, usually a username and password combination to access network resources. Share-level security is not as secure as user-level security. Password level and Layered are not accepted terms for describing levels of security.
Answer: B. Data that is being accessed by another user is placed in Read-Only mode, so that subsequent users accessing the same data at the same time cannot overwrite simultaneously the work being done by the first user.
Answer: A. Replacing hubs with switches is a practical, economical, and very effective way to improve performance on twisted-pair networks. It is the accepted upgrade path in hub-based networks. Although implementing switches is a valid approach, the cost of doing so may be prohibitive, and it is not the best option of those given. Implementing a router is not the most likely approach and would require extensive reconfiguration of the network. Implementing a bridge is not the most likely approach.
Answer: D. A 100BASE-FX fiber-optic NIC will not work with 10BASE-T UTP copper cabling.
Answer: B. When a new card is installed on a token ring network, the speed of the card has to be set to match the speed used by the network. Token ring networks operate at either 4Mbps or 16Mbps. Full-duplex connections are not used on token ring networks. Although it is possible, it is not the most likely that the card is faulty.
Answers: A, B. Because there are multiple segments, a routable protocol is required. Both NetWare and Windows 2000 support the routable TCP/IP and IPX/SPX. The Point-to-Point protocol (PPP) is used for dial-up connections, not as a network transport protocol. NetBEUI is not a routable protocol, nor is it supported by NetWare. Therefore, it is not a suitable protocol for the given configuration.
Objective 3.3
Answer: D. A time domain reflectometer can be used to find the exact location of a break in the cable. A voltmeter can be used to see whether there is continuity of a cable, but it will not tell you where the break is, if one exists. A tone generator and locator can be used to find a cable that is faulty, but it will not help you find the location of the break. Wire taps are used for taking a signal off a line for the purpose of eavesdropping.
Answer: A. A tone generator and locator are two tools used for tracing cables. Collectively they are often referred to as the "fox and hound." A time domain reflectometer is a tool used to locate a break in the cable. A voltmeter is used to measure electrical connectivity and voltages. "Cable chaser" is not a commonly used term. Wire taps are used for taking a signal off a line for the purpose of eavesdropping.
Answer: C. A token-ring media filter is used to interface a token-ring adapter card to a UTP cable.
Answer: C. A cable tester may be equipped with LEDs that illuminate for each wire that isn’t broken, or it may emit a tone to indicate connectivity across the length of the cable.
Answers: A, C. A hardware loopback plug connects the 2 and 6 wires and 1 and 3 wires to simulate a live network connection. The remaining possible answers are not correct for the cabling in a hardware loopback adapter.
Answer: B. A crossover cable is required for this connection. The MDI connection indicates that the hub does not perform the crossover function internally.
Answer: D. Network Monitor and Performance Monitor, both used with Windows NT, 2000, and 2003 operating systems, are examples. They have the advantage of displaying network-related information in both real-time (as it occurs) and in recorded-time (in a log file to be viewed at a later date).
8. Answer: C. A punch down tool will be required to make the connections in the company’s wiring closet between the incoming line (or lines) and the fan out of cables into the building.
9. Answers: B, C. A TDR can be used to place active signals on a copper cable for testing. This device measures the amount of time between when the signal is placed on the wire and the time it is reflected back to source. It uses this timing to determine such things as the distance to breaks in the line. The line tester is a simpler device that places signals on the wires and detects them through a loopback process, made possible by a special attachment that must be installed at the end of the cable.
Objective 3.4
Answer: B. Because the same IRQ has been assigned to both NICs, locate any available IRQ to resolve the IRQ conflict. Changing the I/O of the second NIC to B800–B81F is incorrect because the I/O addresses must be unique. The IRQ 10 assigned to both NICs will create a hardware conflict. Locating any available I/O range to resolve the I/O conflict is incorrect because there is no I/O conflict.
Answer: B. There is no apparent resource conflict associated with these settings. However, there could be conflicts with other installed devices. So if actual errors occur with these settings, the resource settings of the other devices in the system should be checked.
Answer: B. Interrupt Request (IRQ) is a setting, assigned to each device in a computer, that’s used to get the attention of the microprocessor. All devices must be assigned unique IRQs so the processor can tell which device it’s servicing. IRQ3 is used on COM 2 or COM4.
Answer: D. The following resources should be configured up for a modem installation: COM port, I/O Address, and Interrupt request settings.
Answer: A. If you have a standalone modem connected to an ISP from your home, you connect to the ISP using the point-to-point (PPP) protocol.
Answer: B. The correct access path to configure RAS on a Windows 2000 Server is Start, Programs, Administrative Tools, Routing, and Remote Access.
Answer: B. If the user is able to access the Internet, then the problem isn’t with the Internet settings. The first thing to do is to attempt a reconnection of the VPN, which is used to allow remote users to access internal corporate resources with the proper credentials.
Answer: C. SASL, or Simple Authentication and Security Layer, is what Apple servers use to determine what authentication protocol to use, if a service is not using Kerberos servers.
Objective 3.5
Answer: B. A firewall server acts to prevent users on external networks from accessing the internal network. You can use any of the popular operating systems as a base for running a firewall application. Browser security does not secure the network itself. A Proxy server system does not actually offer any security, although the proxy functionality is combined with firewall functionality in some products.
Answer: A. Firewall systems protect a network from attack by outside sources. They are placed at the edge of the private network, so they can control traffic from a single point. Although firewalls can be placed at any point on the network, they are not normally placed between two internal networks or between client systems and servers. Firewalls normally reside at the edge of the private network boundary, not outside it.
Answer: D. Because the IP addresses have been made public—or can be deduced from a company’s public presence on the Internet—they are ready targets for intruders. The key point in the question is to determine a means of thwarting outsiders from accessing the network. From the selections, only a firewall filters those whose source IP can be authenticated.
Answer: A. The purpose of the firewall system is to protect one network from another. One of the most common places to see a firewall is to protect a private network from a public one such as the Internet. Although a firewall can provide a single point of access, this is not its primary purpose. A Proxy server allows hostnames to be resolved to IP addresses. A DNS server provides a single point of access to the Internet.
Answer: A. To prevent unauthorized access into a private network from the Internet, you can use a firewall server to restrict outside access. Implementing a more secure password policy may be a good idea, but it is not the best choice of those available. Implementing a file level encryption system may be a good idea, but it is not the best choice of those available. Kerberos is an authentication system, not a method to prevent unauthorized access to the system.
Answer: B. A firewall can provide several different services to the network, including Network Address Translation (NAT), proxy and packet filtering. NAS is Network Attached Storage and is not a function of a firewall server.
Answer: A. A firewall is software or hardware that’s specifically used to prevent intruders from entering a network.
Answer: B. Packet filtering firewalls operate at the network and transport layers.
Objective 3.6
Answers: A, B, D. Using a caching Proxy server allows Internet access to be centralized. Caching Proxy servers reduce the demand on the Internet connection because commonly used Web pages are retrieved from the cache rather than being retrieved from the Internet directly. It is faster to retrieve commonly used Web pages from a cache than from the Internet directly. Automatic assignment of IP addresses to workstations is the function of a DHCP server. Protection of the internal network from attack by outside sources is a function of a firewall system.
Answer: C. A Proxy server is used to prevent network workstation IP addresses from being advertised on the Internet. The Proxy server performs all packet filtering. In addition, the proxy will replace a workstation IP address with a proxy IP address and may also authenticate users via a password for connecting to the Internet.
Answer: D. For traffic inbound from the Internet, the firewall may be configured to prevent any Internet application such as FTP uploads or email. In addition, the firewall may reject all packets that are broadcast to all workstations connected to the Internet. This prevents the network workstations from being a target or unwitting accomplice in attacks against the network.
Answer: C. The purpose of a proxy is to prevent an outsider from learning IP addresses of workstations and servers with the network. Because the outsider doesn’t know the IP address of any device on the network, the physical location of the device can’t be learned, either.
Answer: A. A proxy server caches web pages, so that pages that tend to be frequently accessed overtime will instead be handled by the proxy server, resulting in fewer times that web pages have to be accessed over the Internet, resulting in less bandwidth requirements.
Answer: C. A Proxy server resolves hostnames to IP addresses and replaces workstation IP addresses with proxy IP addresses. The purpose of the firewall system is to protect one network from another. One of the most common places to see a firewall is to protect a private network from a public one such as the Internet. Although a firewall can provide a single point of access, this is not its primary purpose.
Answer: A. A proxy server operates at the application layer of the OSI model.
Objective 3.7
Answer: A. Passwords should not be included in documentation because doing so represents a security risk. Ensuring that passwords are not reused, making sure that users use only "strong" passwords that are a certain length, and changing passwords on a periodic basis are valid procedures that should be included in a password policy.
Answer: C. PaSsWoRd1 contains a mix of upper-and lowercase letters, as well as a number. All other answers contain limited choices that an intruder must attempt when guessing a password. Note that PASSWORD1 is less secure than PaSsWoRd1 because PASSWORD1 contains all uppercase letters.
Answer: B. It implies that a network must be planned before any implementation efforts are made. All other answers are incorrect because they involve activities that should occur after the planning stage.
Answer: A. POP3 operates on Port 110. While there are other services between ports 100 and 200, the other options listed are FTP = 20 and 21, SMTP = 25 and HTTP = 80.
Answer: C. Changing passwords too frequently is not practical and represents a security risk. Monthly password changes are typically adequate for most environments. Changing passwords too frequently can cause problems as users may have trouble remembering passwords and use passwords that are too similar. Although passwords should be changed if they are compromised, they should also be changed periodically.
Answer: C. UNIX/Linux uses the HOSTS file to resolve logical names with their corresponding IP addresses.
Answer: B. User-level security is more secure and requires a user to provide a login ID, usually a username and password combination to access network resources. Share-level security is not as secure as user-level security. Password level and Layered are not accepted terms for describing levels of security.
Answer: A. The HOSTS file is used to manually configure host name resolution and if there is a problem with host name resolution, entries in this file must be checked. Resolv and staticdns are not used on a Linux system. The passwd file is used to store user account information.
Answer: C. The Attribute file permission is not a valid Linux file permission. The rest of possible answers are all valid file permissions on a Linux system.
Answer: A. Users should be given the option of changing passwords whenever they want. If this isn’t possible, establish a policy that forces them to do so at least once a month. Normally, a notice pops up when the monthly time limit approaches, say 10 to 15 days before. Users then have two weeks to make the change. If they don’t, they’ll be prohibited from logging on when the password expires. This is a good system because it incorporates randomness into password changes. If all users change passwords on the same day at the same time, it won’t be too difficult for a hacker to be in the right place at that specific time to catch the new password. Randomness makes it far more difficult for this to happen.
Answer: A. Users should be given the option to change passwords whenever they want. If this isn’t possible, establish a policy that forces them to do so at least once a month. Normally, a notice pops up when the monthly time limit approaches, say 10 to 15 days before. Users then have two weeks to make the change. If they don’t, they’ll be prohibited from logging on when the password expires. This is a good system because it incorporates randomness into password changes. If all users change passwords on the same day at the same time, it won’t be too difficult for a hacker to be in the right place at that specific time to catch the new password. Randomness makes it far more difficult for this to happen.
Answer: D. Users should be given the option of changing passwords whenever they want. If this isn’t possible, establish a policy that forces them to do so at least once a month. Normally, a notice pops up when the monthly time limit approaches, say 10 to 15 days before. Users then have two weeks to make the change. If they don’t, they’ll be prohibited from logging on when the password expires. This is a good system because it incorporates randomness into password changes.
Answer: D. Secure web pages are viewed using HTTPS. HTTPS uses port 443, which is different from a normal web page that uses HTTP over port 80. Therefore, in this scenario, the most likely explanation is that port 443 is being blocked by the firewall, preventing people from accessing any pages that use HTTPS. Standard web pages use HTTP, which uses port 80 by default. Because users can access other areas of the website, this is not the problem. Port 110 is used by POP3, an email retrieval protocol, and is therefore unrelated to this problem. Because users still can access other areas of the website, it does not block all traffic.
Answer: A. SMTP operations reside on port 25. If the firewall has not been configured to allow data on that port, SMTP operations will be blocked, legitimate or not.
Answer: C. Accessing web pages qualifies as HTTP operations, which reside on port 80. If the firewall has not been configured to allow data on that port, all web page access will be blocked, legitimate or not.
Answer: A. A security policy should include keeping user names and passwords at or below eight characters so as to avoid errors when entering, and also to reduce the likelihood of the user forgetting them. Because most password encryption schemes are case-sensitive, the password should include a mix of upper- and lowercase letters as well as numerals and special characters.
Objective 3.8
Answers: A, B, D. VLANs can be created using the IP address, the switch port assignment, or the MAC address of the connected devices. Computer names are associated with NetBIOS and are not used to create VLANs.
Answer: B. VLANS are implemented on a switch to create multiple separate networks. A Proxy server is used to control access to the Internet. Subnet masking is not a valid method of creating separate networks. Network Attached Storage (NAS) describes storage devices that are attached directly to the network media.
Answers: A, C, D. VLANs can be created using the IP address, the switch port assignment, or the MAC address of the connected devices. Computer names are associated with NetBIOS and are not used to create VLANs.
Answer: C. Virtual Private Network (VPN) is a technology that allows a secure tunnel to be created across a network such as the Internet. VPNs can be used to secure a dial-up connection for a remote user or link two sites. 802.11b is an IEEE standard for wireless networking. Virtual LANs (VLANs) are a technology implemented in network switches that allow areas of the network to be segregated from each other using a variety of criteria. A time domain reflectometer (TDR) is a tool that allows you to locate a break in a length of cable.
Answer: C. A VLAN is able to separate a larger network into smaller logical networks. These smaller networks could potentially lower total bandwidth usage.
Answer: A. VLANs require the use of a router to communicate with each other.
Answer: D. Pinging the VPN host will allow you to determine if the VPN is operational or not. If it is not, bringing the VPN back to functionality will fix the problem.
Objective 3.9
Answer: C. The model of two companies working together to share data across the internet can be accomplished via an extranet. An extranet is a private network that supports Internet applications and uses the public telecommunications system to share company information with users, customers, and partners.
Answer: B. An intranet is a private network that supports Internet applications and doesn’t use the public telecommunications system to connect users.
Answer: B. An intranet is a private network that supports Internet applications and doesn’t use the public telecommunications system to connect users, which offers the best security.
Answer: B. An intranet is a private network that supports Internet applications (such as email and web browsing) but does not use the public telecommunications system to connect users. The web server in an intranet may be used only for an internal website that isn’t accessible from the public Internet.
Answer: D. An intranet is a network built on the TCP/IP protocol that belongs to a single organization. It is, in essence, a private Internet. Like the Internet, intranets are designed to share information and services but they are accessible only to the organization’s members with authorization. In an intranet system, a local web server provides Internet applications, such as email, FTP, and web browsing for the network without using the public telephone system.
Answer: D. A hardware or software firewall is typically employed to block unauthorized, outside users from accessing the intranet site.
Answer: B. The Internet, not an intranet, is designed to be publicly available.
Answer: C. An extranet is a private network that supports Internet applications and uses the public telecommunications system to share company information with users, customers, and partners.
Answer: B. An extranet is a private network that supports Internet applications and uses the public telecommunications system to share company information with users, customers, and partners. Essentially, an extranet extends an intranet to the public Internet. Parts of an extranet remain private and separate from the Internet, while other parts of it are accessible from the Internet.
Answer: C. An extranet is a private network that supports Internet applications and uses the public telecommunications system to share company information with users, customers, and partners.
Answer: A. An extranet is a private network that supports Internet applications and uses the public telecommunications system to share company information with users, customers, and partners. Essentially, an extranet extends an intranet to the public Internet. Parts of an extranet remain private and separate from the Internet, while other parts of it are accessible from the Internet.
Objective 3.10
Answer: A. Antivirus software can stop Trojan programs. However, other software would have to be installed to effectively deal with the problems posed by spam, pop-up ads, and spyware.
Answer: A. A computer virus is an unwanted software program that can attach itself to another program on a disk or hide in a computer’s memory, and can multiply from one system to another.
Answer: A. All workstations should have antivirus software installed including an email server. Email received from the Internet is the most common source of viruses.
Answer: B. Proxy servers represent a potential hole through which intruders may enter a network. Since a proxy server receives all HTTP responses from web servers, it may also be a source for viruses. The best protection against web server viruses is to install antivirus software on all proxy servers along with all client workstations.
Answer: B. For an antivirus software package to be most effective across a network, one guideline to follow is before installing a new application, the user should deactivate the antivirus scanner.
Answer: B. All email attachments should be scanned before opening them because email is the most common carrier of viruses from the Internet.
Answer: D. For users that have an FTP client, you should ensure that FTP files are scanned for viruses when opened, before being saved to a disk, and before being executed.
Answer: C. You should update virus signatures on a monthly basis (at a minimum), and more often for recent virus attacks.
Answer: D. When receiving code from a third party, be sure to scan it for viruses before using it.
Objective 3.11
Answer: A. Disk striping with parity (RAID 5) uses a minimum of three disks. With two disks, the only fault-tolerant RAID level that can be implemented is RAID 1 (disk mirroring). There are no fault-tolerant configurations that only use a single disk. With four disks, it is possible to implement RAID 5, although only three disks are actually required.
Answer: D. Striping with parity means that data is written in stripes of bits, or bytes, usually across multiple hard drives. Parity refers to a section allotted on the drive that’s used to regenerate lost data. Striping enhances drive performance; whereas parity provides for fault tolerance. Tape backup provides for fault tolerance only, but doesn’t address performance. Mirroring provides for fault tolerance but doesn’t necessarily boost performance because writes to the drive must be duplicated to the mirror drive (it typically improves reads from the drive, however). Striping without parity addresses performance but not fault tolerance.
Answer: B. Duplexing is used to provide a dedicated drive controller to each hard drive. This directly addresses fault tolerance and network reliability by providing redundancy. Parity is a reference to using a portion of a drive to regenerate lost data. Striping refers to improving hard drive performance and doesn’t address fault tolerance. SNMP (Simple Network Management Protocol) has nothing to do with dedicated controller cards.
Answers: A, C, D. Disk mirroring (RAID 1) requires two hard disks and a single hard disk controller. Disk duplexing, which is a variation of RAID 1, uses two hard disks connected to two separate disk controllers. Although not a fault-tolerant implementation, RAID 0 uses disk striping to provide increased performance. Two disks are required to implement RAID 0. Disk striping with parity (RAID 5) requires a minimum of three disks. Disk shadowing is not a valid RAID implementation.
Answer: B. An Uninterruptible Power Supply (UPS) is connected in series with a server. The server receives all power from the UPS. A stand-by power supply is used when the main power fails, causing the supply to switch to the SPS. An SPS always has a delay factor that may cause a loss of data during the switching time. Note that both a UPS and an SPS are alternative power supplies. The key to choosing correctly for this question is the hint in the question, "true, continuous power." Only a UPS provides this.
Answers: A, B, C. With two hard disks and two controllers you can implement RAID 0, RAID 1, and disk duplexing. RAID 5 (disk striping with parity), requires a minimum of three disks to be implemented. RAID 10 is a combination of RAID 1 (disk mirroring) and RAID 0 (disk striping). It requires a minimum of four disks.
Answer: A. A RAID 5 array consists of at least three hard disks and stripes parity information across all disks in the array.
Answer: D. Fault tolerance promotes data availability by eliminating a single point of failure. It may reduce the reliance on backups, but they should still be performed. A fault-tolerant system does not help a system be brought back on line more quickly. Fault tolerance does not protect data from accidental deletion.
Answer: A. Striping means that a block of data is separated and alternately written to sectors on each of the three disks. For example, suppose a 48KB file is written to the disks. RAID 0 will write 16KB to the first drive, 16KB to the second drive, and 16KB to the third drive. In other words, data blocks are striped across the fixed disks.
Answer: B. RAID 0 doesn’t provide for redundancy; therefore, it has no fault tolerance attributes. RAID 0 provides improved throughput without parity. Parity is used with the other levels as a means for regenerating data, if it’s lost on any of the fixed disks. If a fixed disk is lost in a RAID 0 system, all data is lost, and there is no means of recovering it; that is, it has no parity for data recovery.
Answer: D. A technique for avoiding this possibility is to duplex RAID 1 by using separate disk controllers for each fixed disk. Duplexing refers to the practice of using a separate disk controller for each fixed disk.
Answer: D. RAID 1, in which data on a primary disk is copied to a mirror disk. Mirroring is a RAID term meaning simply that all data written to one hard drive is simultaneously written to a backup—or mirror—hard drive.
Answers: A, B, C. Installing a UPS, a RAID system, and a mirror server all represent steps aimed at keeping the system going when something breaks down. Performing a backup is an activity designed for disaster recovery instead of continuation.
Answer: A. Duplexing the RAID 1 system by adding an additional controller removes the controller as a single point of failure.
Answer: B. Striping with parity means that data is written in stripes of bits, or bytes, usually across multiple hard drives. Parity refers to a section allotted on the drive that’s used to regenerate lost data. Striping enhances drive performance; whereas parity provides for fault tolerance. Tape backup provides for fault tolerance only, but doesn’t address performance. Mirroring provides for fault tolerance but doesn’t necessarily boost performance because writes to the drive must be duplicated to the mirror drive (it typically improves reads from the drive, however). Striping without parity addresses performance but not fault tolerance.
Answer: B. Because the drive subsystem is duplexed, the drives will remain intact and will operate from the remaining controller. However, the performance will decrease because now only one channel is open for data movement.
Answer: A. Because the data drives are striped without any sort of parity, when one drive fails, both drives are rendered inoperable. There is no ability to rebuild the drives, so one would have to replace the drive and restore the contents from backup.
Answer: D. Striping offers no fault tolerance. Mirror and duplexing both require that half the hard drives be used for data redundancy. Striping with parity takes one hard drive’s worth of data and uses it for parity purposes.
Answer: D. RAID 0 offers no fault tolerance. RAID 1 and mirroring both require that half the hard drives be used for data redundancy. Striping with parity takes the equivalent of one hard drive’s worth of space and distributes it across all the drives for parity purposes.
Answer: C. A volume is used to subdivide partitions into smaller units. With four allowable partitions on each disk, you can have up to eight volumes on a disk. Whereas a partition is limited to a single disk, a volume can span multiple disks. A volume is organized into logical groupings, such as user directories for various departments (for example, sales, production, and so on). A volume can also be created to contain application software available across the network.
Objective 3.12
Answers: A, B. In an incremental and a full backup, files that are copied to the backup media have the archive bit cleared. A differential backup does not clear the archive bit. Periodic is not an accepted backup method.
Answer: C. Grandfather, Father, Son (GFS) is a backup rotation system that incorporates daily, weekly, and monthly backups. RAID rebuilds are only performed on an as- and a when-needed basis. Tapes should be replaced in a backup cycle periodically, although there is no accepted standard for this action.
Answer: D. A normal backup, also called a full backup, is used to copy all files on a server or workstation, or files that have been selected for copy.
Answer: B. An incremental backup is performed only on files that have changed since the last backup. A full backup is used to back up all selected files, regardless of whether they have changed. Differential is incorrect because this method will back up files that have changed since the last backup as well as all other files that have changed since the last full backup. Differential backups are cumulative, whereas incremental backups are selective. A tape backup is a backup technique rather than a backup method.
Answer: B. A daily normal backup can use as little as one tape. The single tape is used each day to perform a full backup of the server data.
Answer: B. Although this is subjective, note that as a general rule, a full backup occurs on a weekly basis.
Answer: A. Differential is used to back up files on a server. The advantage is that it is easier to restore from this because you only need the last full and the latest differential. It is also less time consuming during backups than repeatedly performing full backups. The disadvantage is that with each differential backup, more tape space is needed progressively closer to the requirements of a full backup.
Answer: B. A weekly normal backup provides a full backup to the server. The daily incremental backups are short because only files that have changed since the last incremental backup are copied.
Answer: D. Environmental disasters include fire, theft, flooding, or a crash of the server hard drive.
Answers: A, B. Both the full and incremental backup methods clear the archive bit. This indicates which data does and does not need to be backed up. In a differential backup, the archive bit is not cleared. Sequential is not a type of backup.
Answer: B. Normal backup, also called a full backup, means that all data on a hard drive is backed up, regardless of the state of the archive bit. Because all data from the hard drive is backed up this backup takes the longest.
Answer: C. Sometimes a full backup is needed —perhaps once a week—but it should be augmented with more efficient planning.
Answer: D. Normal backup, also called a full backup, means that all data on a hard drive is backed up, regardless of the state of the archive bit.
Answer: A. Servers and workstations employ data backups in the event of a disaster that may destroy crucial data. The most common method used to back up data is tape. A tape backup system is used to back up the data stored on fixed disks.
Answer: D. A differential backup occurs for all files that have changed since the last full backup, regardless of whether they changed since the last differential backup. The archive bit is set to 1 when the file is modified and not reset after the backup.
Answer: B. Incremental backup occurs only on files that have changed since the last full backup. A change to a file will set the archive bit to 1, thus flagging it for the backup.
Answer: C. The only reliable way to be certain that a backup system will perform correctly in the event of a failure is to actually perform a Restore operation in a test environment when no actual problem exists.