Netw240FinalStudy

The root directory for anonymous FTP users is

/var/ftp.

_____ and _____ DNS servers define the hosts for a particular domain, such as technowidgets.com.

Primary, secondary

The most common place for the boot loader to reside is on

the master boot record.

The switch used by the cp, mv, and rm commands that will eliminate the prompt when a file is about to be overwritten or deleted is

-f.

The file that holds all of the group information is called

/etc/group.

The _____ Linux command will erase the terminal screen and return the cursor to the top left-hand side of the screen.

clear

What is the name of the DHCP daemon in Linux?

dhcpd

FTP stands for

file transfer protocol

The first installed Ethernet network interface card (NIC) in a UNIX workstation is labeled as

ifcfg-eth0.

The fully qualified domain name (FQDN) for a network host named sales at the XYZ Corporation that belongs to the DNS top-level .com would be written out as

sales.XYZ.com.

What service typically provides remote file services for Linux clients?

nfsd

The core component of the Linux operating system is called the

Linux kernel.

The Linux command that is used to delete files and directories (similar to the MSDOS DEL command) is

rm.

The top domain in the domain name space is known as

root.

When configuring your DHCP server, how would you set the default IP address of the primary and secondary DNS to be 10.0.0.1 and 10.0.0.2 respectively?

Option domain-name-servers 10.0.0.1 10.0.0.2;

Host names and fully qualified domain names (FQDNs) can be resolved statically on individual Linux computers by configuring the file

/etc/hosts.

What is the directory of the Apache configuration file?

/etc/htppd/conf

The _____ option for the useradd command specifies the number of days after the password expires until the account is disabled.

-f

To view a list of files and its types, use the _____ switch to the ls command.

-F

The Linux operating system character that is used to separate subdirectory names is

/

When using useradd, if you create an account called amoffett, the default home directory will be

/home/amoffett.

A user with the username jsmith will have the default directory _____ assigned to him for his private use.

/home/jsmith

A run level is essentially what state your system enters in. Here are the different types of Run Levels, in which there are 0-6.

0 - System halt i.e the system can be safely powered off with no activity. 1 - Single user mode. 2 - Multiple user mode with no NFS(network file system). 3 - Multiple user mode under the command line interface and not under the graphical user interface. 4 - User-definable. 5 - Multiple user mode under GUI (graphical user interface) and this is the standard runlevel for most of the LINUX based systems. 6 - Reboot which is used to restart the system.

When using the chmod command, the mode rwx can be represented by the number

7

Setting Up a Local Area Network (LAN)

Chapter 15 in the text offers a review of networking. Let us focus on the section in Chapter 15 that provides us with the steps required to configure a Linux workstation for LAN connectivity. [Administrative Tasks]: Determine a domain name for the network. Determine an IP address for the network. Determine the IP address range(s) or subnet(s). Determine a gateway IP address for the router. Determine a boot protocol type, DHCP, or static IP assignment. Determine a host name for each client and server in the network. [Hardware Connectivity Tasks]: Determine network hardware locations for workstations, servers, and switches. Install Category 5e or higher cable to each host location from a central switch. Install RJ45 connectors on each cable run and certify with a cable tester. Connect all workstations to the LAN switch. Connect all server(s) to the LAN switch. Connect and configure a router to the central switch for WAN connectivity. [Host Configuration Tasks (Each Networked Host)]: Configure each host with a fully qualified domain name as a host name. Configure the /etc/sysconfig/network file with networking and hostname options. Configure the /etc/resolv.conf file with network domain name and nameserver IPs. Configure the /etc/nsswitch.conf file with the appropriate DNS search order. Configure the /etc/hosts file with each local host IP address, FQDN, and alias. Configure the /etc/sysconfig/network-scripts/ifcfg-eth0 file with a protocol type, boot protocol, on-boot parameter, host IP address, host subnet mask, network IP address, and gateway IP address. Configure the kernel routing table with the localhost IP address, network IP address, and all locally attached host IP addresses. Use the ifconfig command to verify network interface card (ifcfg-eth0) configuration. Use the service network restart command to turn on network services. Use the ping command to verify host-to-host connectivity for all hosts.

NetworkManager Commands

Check for NetworkManager: # rpm -qa NetworkManager* Install NetworkManager: # yum install"NetworkManager*" Start NetworkManager: # service NetworkManager start # chkconfig NetworkManager on The nmcli command provides a command-line interface to the Fedora NetworkManager using a syntax whereby you specify the network-related object you're interested in along with a network command. # nmcli -p dev A VPN provides a way to create secure communications over an otherwise insecure network. With a VPN connection in place, the two sides of a connection can communicate as safely as they do on the same corporate LAN. To do this, a VPN usually offers the following features: Authentication — Using passwords or other techniques, two ends of a communication can prove that they are who they say they are before accepting a connection. After the connection is in place, communications can flow in both directions across it. Encryption — By encrypting all data being sent between the two points on the public network, you can be assured that even if someone could see the packets you send, they couldn't read them. Creating a connection between two public network addresses to use for exchanging encrypted data is known as tunneling.

Which service allows an administrator to dynamically assign IP addresses to host computers on a network?

DHCP

Which protocol is used by web servers for communication?

HTTP

How important is it to follow an HCL if it is available?

Hardware Compatibility Lists (HCL) sometimes are ignored, but remain crucial of any new deployment. There seems to be a myth that the various Hardware Abstraction Layers (HAL) enable any hardware to work with anything. Drivers still must be compatible and the vendor still needs to confirm that the hardware you want to use will work with their software. There are software compatibility lists as well. A hardware compatibility list (HCL) is a detailed list of hardware that is compatible with the operating systems currently running in the environment. It's important to have this list available and updated to ensure newly installed hardware will work and function as expected when added to the environment. If hardware that's not compatible is added to the environment, it could cause performance issues, outages or the hardware may not perform as expected.

advantages of utilizing Linux in the work place

It does not slow down overtime Restores old computer through installation Reduced vulnerability to malware Stability to crashing Free software accessibility Open source software ability to variety

Which of the following is not required when setting a static IP address?

Lease time

Log File Administration

Log files are used to identify and troubleshoot problems on a Linux system. Linux log files are typically stored in the /var/log directory.

Managing Log Files

Log files contain important system and security information. Over time, log files become large, taking up critical storage space. Clearing log files can be done by printing out their contents or by backing up their contents for future reference. Log files should never be removed, because their permissions would be removed also.The logrotate utility automatically backs up and clears log files. logrotate is configured using the /etc/logrotate.conf file. Application and utility (rpm) files are configured in the /etc/logrotate.d file, which is controlled by logrotate.

The System Log Daemon

Logging of most events occurring on a Linux system is handled by the system log daemon named rsyslog. A socket is started upon system boot-up named /dev/log (remember that the /dev directory stores all input/output channels, or drivers, for device files). As /dev/log reads information, it is stored in the appropriate log file according to entries in /etc/syslog.conf. As with most conf files, removing the pound symbol (#) at the beginning of a line will activate the service specified on that line.

Static Hostname Resolution on Small LANs

On a small business LAN, a DNS server may not be practical. To overcome this issue, host names can be mapped to IP addresses using the /etc/hosts file. Using vi, configure this file with an IP address, FQDN, and alias (optional) for each workstation sharing the network segment. The localhost IP address of 127.0.0.1 must be populated in this file for the operating system to NIC connectivity. Line entries in /etc/hosts would look as follows: 127.0.0.1 localhost.localdomain lo 192.168.240.20 sales.ABC.com sales 192.168.240.21 services.ABC.com services It is important to separate each column in UNIX configuration files with an ASCII space (null). Ensure that each column stays aligned left for easy reading when troubleshooting or verifying line entries.

Client computers can retrieve e-mail from e-mail servers via _____ or _____

POP3; IMAP.

TCP/IP Utilities

Please note that this is not an all-inclusive list. You are encouraged to research, on your own, some of the other tools that you might want to use: ping: Sends packets to a host and expect an answer back. The ping used in Linux will not stop until the user stops it. traceroute: Similar to ping, except that traceroute will tell you how many hops it takes to reach the destination. nslookup: Sends a message to the DNS server and asks for a name, or uniform resource location, for a specific IP address. netstat: It provides a well-informed status of the network. You can find out which servers and gateways are attached to your network. dhclient (pump): If your machines receive their network addressing information dynamically, then this tool allows the client to talk to the server and receive its IP address, subnet mask, DNS, and default gateway information. Some distributions of Linux use the pump command to request a new DHCP lease from a server.

What type of server acts as a middleman between your LAN and the Internet?

Proxy

The iptables option that prevents the packet from being accepted and responds with an ICMP message is

REJECT.

What is the oldest routing protocol still in common use?

RIP

The SQL _____ clause is used to specify the fields (or columns) to be accessed from a database.

SELECT

Which distro __________ is not a distribution of Linux.

SoSe

Name Resolution and DNS

The domain name space (DNS) consists of a hierarchical naming scheme developed for the Internet to allow a fully qualified domain name (FQDN) to be matched to its assigned, public IP address and vice versa. The top level of DNS is named root and designated with a dot (.). Directly below root are top-level domain names, such as .com, .gov, .mil, .edu, .net, and many others. Each DNS level is separated by a dot. The UNIX administrator is responsible for connecting his or her company's network to the domain name space according to the company's registered domain name.If we worked for the ABC Corporation, our network name could be ABC. We would then register our network as ABC with connectivity into the top-level domain of .com as a commercial organization. Our company's domain name is now ABC.com. Next, our registered, public IP address for ABC.com must be entered into Internet DNS servers along with our new domain name—this is usually performed by the organization that sells us our public IP and domain name. The UNIX administrator then configures our ABC Corporation DNS server with ABC.com. Now, anyone on the Web can communicate with us via our IP address or domain name.Next, we link each network host name to our domain name of ABC.com. For example, three hosts named sales, services, and financial become sales.ABC.com., services.ABC.com., and financial.ABC.com. Notice how an FQDN ends in a dot (.). This is usually done by default by the DNS server.

TCP/IP

The dominant set of protocols for the transfer of data over the Internet. Newer versions of Novell implement TCP/IP directly instead of IPX/SPX. Microsoft still uses NETBIOS naming conventions but uses NETBIOS over TCP/IP to interact with TCP/IP networks. Not only does TCP/IP allow computers to talk with each other, it also allows other important infrastructure equipment, such as routers, switches, and servers to communicate.

Locations and Labels

To troubleshoot network problems, the Linux administrator must be able to identify network files and verify configuration settings. Common files in /etc are HOSTNAME, resolv.conf, host, hosts, sysconfig/network, and sysconfig/network-scripts/ifcfg-eth0. Linux refers to the network interface card (NIC) as ifcfg-eth0. The first installed NIC is labeled ifcfg-eth0, the second installed NIC is ifcfg-eth1, and so on. The ifcfg designation is interface configuration. The eth0 designation is Ethernet 0. For token-ring NICs, the labeling is ifcfg-tr0, ifcfg-tr1, and so on. The ifconfig command displays all interface settings.

DHCP uses which port(s) as the source port?

UDP 67 and 68

Kudzu and Modprobe

Upon boot-up, Fedora Linux runs a plug and play service, Kudzu, which identifies most hardware, including the NIC. Kudzu then loads the appropriate hardware driver for each device. If hardware cannot be identified by Kudzu, or if a driver cannot be loaded, the Linux administrator must find and load the driver into the kernel. Drivers are located in the /lib/modules directory. If a particular driver is not found in /etc/modules, the Linux administrator can use the insmod or modprobe command to load the driver. Use the lsmod command first to view all loaded modules. Some wireless NICs do not have drivers in /etc/modules because some wireless NIC manufacturers have not released the driver microcode to the Linux community so that a driver can be created.

The SQL _____ clause is used to indicate the conditions by which records will be accessed from a database.

WHERE

Data transfers typically pass through

a port above 1023.

Which command is used to create groups?

groupadd

The feature of an operating system that allows a computer to run more than one program at the same time is called

multitasking.

The concept of _____ enables software developers to read other developers' source code, modify that source code to make the software better, and redistribute that source code to other developers who might improve it further.

open source software

This command line tool is used to determine if a particular network device is reachable.

ping

The FTP command to upload a single file is

put.

Which command is used to view the current directory you are working in?

pwd

To exit the help text in Man (Manual) pages, you have to press

q.

Which command will unpack the tarball labs.tar?

tar -xf labs.tar

During Linux installation, you need to configure a minimum of _____ user account(s).

two

Which command is used to create user accounts?

useradd

The configuration file for FTP using vsFTPd in Linux is

vsftpd.conf.