Linux -Chapter 13 - Configuring Network Services

What FTP command runs a shell on the local computer?

!

Which file stores the Apache configuration in Fedora 20?

/etc/httpd/conf/httpd.conf

What directory are you placed in when you log in as the anonymous user to an Ubuntu Server 14.04 FTP server?

/srv/ftp

In order to look up IPv4 and IPv6 DHCP leases, what two files should be viewed?

/var/lib/dhcpd/dhcpd.leases for IPv4 /var/lib/dhcp/dhcpd6.leases for IPv6

What zone configuration file contains a PTR record used to identify the loopback adapter?

/var/named/named.local

Where is the default document root directory for the Apache web server?

/var/www/html

In NTP, what stratum consists of atomic devices or GPS clocks?

0

What is the maximum number of characters that can be used in a NetBIOS name?

15

How can you specify the intended DNS server to query with the dig command?

@server

What two resources record types map FQDNs to IPv4 and IPv6 addresses respectively?

AAAA A

Which DNS resource record is an alias to other records?

CNAME

Which SQL statement key word can be used to delete a record within a table?

DELETE

What kind of servers resolve fully qualified domain names to IP addresses for a certain namespace on the Internet?

DNS

What SQL statement can be used to delete a database:

DROP DATABASE

What directive in Apache's httpd.conf file specifies that the index.html file in the document root directory will be sent to clients who request an HTML document?

DirectoryIndex index.html

NFS can be used to share files natively with computers running the Microsoft Windows operating system. True or False

False

NIS clients use NIS records to access their configuration information. True or False

False

The email command is an example of a Mail User Agent (MUA). True or False

False

When connecting to the vsftpd daemon using an FTP client utility as the user "anonymous," you will be placed in the root user's home directory. True or False

False

When working with Sendmail, what command can be used to test SMTP support?

HELO

You have opened a telnet session on port 25 with your e-mail server. What command can you type within your telnet session to start an e-mail session? (choose all that apply)

HELO EHLO

What two protocols are used for mail retrieval?

IMAP POP

What is NFS? How do you access files using a configured NFS Server?

Network File System (NFS) is a set of software components that can be used to share files natively between UNIX, Linux, and Macintosh computers on a network to share files transparently. In NFS, one computer shares (or exports) a directory in the directory tree by placing the name of that directory in the /etc/exports file. The other computer can then access that directory across the network by using the mount command to mount the remote directory on the local computer.

To share information to Windows client computers, you can use the ______________ daemon, which emulates the SMB protocol.

Samba (smbd)

The Apache daemon listens for HTTP requests on what port by default?

TCP 80

How does DHCP automatically configure IP addresses?

The device (the client) requests an IP address from a router (the host), then the host assigns an available IP address so that the client can communicate on the network. This is done by using the Discover, Offer, Request and Acknowledgment process also known as (DORA). Discover = a request is sent to the DHCP server Offer = Offers an IP address available that the device can use Request = device responds to the DHCP server with the request to accept the address sent. Acknowledgment = server send and ACK to confirm that the device has and will use the specific IP address and defines also the time this IP address will be used by issuing a lease.

All DNS servers contain a DNS cache file. True or False

True

By default, the smb.conf file shares all printers and home directories for recognized Windows users. True or False

True

Chronyd is an NTP daemon that offers a faster response time compared to the ntpd daemon. True or False

True

DHCP clients sent a DHCPREQUEST packet when they require a new IP configuration. True or False

True

Stratum 1 NTP servers do not obtain time information from other NTP servers. True or False

True

The Very Secure FTP daemon is a stand-alone daemon. True or False

True

The lines within the Apache configuration file that modify the functionality of the Apache are called directives. True or False

True

What port is used by the Network Time Protocol (NTP) for communication?

UDP 123

In the PostgreSQL utility, the ___________________ built-in command is used to list available databases.

\l

reverse lookup

a DNS name resolution request whereby an IP address is resolved to a FQDN

NIS client

a computer in an NIS domain that receives its configuration from an NIS master server or NIS slave server

DNS cache file

a file that contains the IP addresses of top-level DNS servers

NetBIOS

a protocol used by Windows computers that adds a unique 15-character name to file-and printer-sharing traffic

What two FTP commands can be used to close the ftp utility?

bye quit

What must you do to transform your computer into a DNS server?(choose all that apply)

create zone files create resource records for DNS lookups run the name daemon (named)

Which command can be used at a BASH command prompt to obtain a web page?

curl

Which of the following must you perform to share a directory using NFS? (choose all that apply)

edit the /etc/exports file run the exportfs -a command start or restart the NFS daemons

What command can be used to view and modify the date and time within the BIOS?

hwclock

Which command within the command-line FTP utility can be used to change the current directory on the local computer?

lcd

The first DNS server in a zone is called the ____________________ DNS server.

master or primary

What ftp command uploads the filename from the current directory on the local computer to the current directory on the remote computer, and allows the use of wildcard metacharacters to specify the filename.

mput filenam

What DNS resource record type is used to provide the IP address for the e-mail server for a zone?

mx or MX

After modifying the /etc/aliases file, what command must be run in order to rebuild the aliases database?

newaliases

What PostgreSQL command-line utility backs up PostgreSQL database settings?

pg_dump

In the initial stage of the DHCP lease process, the client sends a(n) _______________________ to all hosts on the network.

request (DHCPDISCOVER) packet

Which command can be used to connect to check the /etc/samba/smb.conf file for syntax errors?

testparm

Which of the following can be used to create a database with PostgreSQL? (choose all that apply)

the CREATE DATABASE statement with the PostgreSQL utility. the createdb command

Jitter

the difference between time measurements from several different NTP servers

Time offset

the difference in time between two computers that use the NTP protocol

DHCPD daemon

the most common Linux daemon used to provide IPv4 and IPv6 addresses to other computers on the network

Describe the structure of a database. When is a database considered a relational database?

A database is a file that contains data that is organized into tables, a table organizes information into a list, inside the list is a record, the various categories of information within a record is called fields. *record types - these define the type of entities or research objects you wish to capture *fields - these are the properties or attributes that describe your record types. A database is considered a relational database when in large databases, the information within certain tables can be related to information within other tables in the same database, usually linked by a common field.

Describe the DNS lookup process

DNS lookup information will be cached either locally inside the querying computer or remotely in the DNS infrastructure. 8 steps in a DNS lookup 1. a user types "example.com" into a web browser and the query travels into the internet and is received by a DNS recursive resolver. 2. the resolver then queries the DNS root nameserver(.) 3. The root server then responds to the resolver with the address of a top level domain such as .com or .net etc. 4. the resolver then makes a request to the .com TLD. 5. The TLD server then responds with the IP address of the domains nameserver, example.com 6. Lastly the recursive resolver sends a query to the domains nameserver. 7. the IP address for example.com is then returned to the resolver from the nameserver. 8. the DNS resolver then responds to the web browser with the IP address of the domain requested initially. once all requests are done the browser is able to make the request for the web page.

What is NIS? What is a master and slave NIS server? Give examples of configuration files that NIS is commonly used to coordinate.

Network Information Service (NIS) is a set of software components that can be used to standardize the configuration files across several different Linux and UNIX computers. NIS master server is the computer in an NIS domain that contains the master copy of all NIS maps. NIS slave server is a computer in an NIS domain that receives a read-only copy of all NIS maps from an NIS master server. Examples of most common files that companies use NIS to coordinate across multiple systems are password databases (/etc/passwd and /etc/shadow).

What two NTP daemons are commonly used on Linux systems?

ntpd chronyd

Which command can you use to synchronize ntpd with an NTP time source?

ntpdate

What command can be used to see what actual time servers are being used for synchronization?

ntpq

Mary is a system administrator in your organization. She has recently made changes to the DHCP configuration file, but the DHCP daemon does not seem to recognize the new changes. What should she do?

restart the DHCP daemon

You have modified the /etc/aliases file to include a new email alias. However, when you send e-mail to the alias, it can not be delivered. What should you do?

run the newaliases command

You can use the __________________ command to connect to both Samba and Windows servers.

smbclient

Which command can be used to connect to a remote Windows share called data on the server called fileserver?

smbclient //fileserver/data

File Transfer Protocol (FTP)

the most common protocol used to transfer files across networks such as the Internet

Zone Transfer

the purpose of copying resource records for a zone from a master to a slave DNS server

Berkeley Internet Name Domain (BIND)

the standard that all DNS servers and DNS configuration files adhere to

In order to change the time zone of a system after installation, what command must be used?

tzselect