Key Vocab

Question 1

Jump Server

Answer 1

-the only server granted specialized access to other servers

Question 2

Virtual Local Area Network

VLAN

Answer 2

-a virtual local area network within a LAN

Question 3

Transmission Control Protocol

TCP

Answer 3

• the basic communication language/protocol of the internet
• enables two hosts to establish a connection and exchange streams of data (assembles messages or files into smaller packets to be reassembled by another TCP)

Question 4

Domain Name Server

DNS

Answer 4

-turns domain names (www.) into IP addresses

$Config file: /etc/resolv.conf

Question 5

Cluster

Answer 5

-group of servers working together to perform one task

Question 6

Redundant Array of Inexpensive Disks

RAID

Answer 6

-multiple hard drives working to back each other up

Question 7

RAID 0

Striping

Answer 7

• 1 hard drive, no backups (fastest, cheapest)

- writes everything to one block and fills it before moving onto the next (A then B then C then D)

Question 8

RAID 1

Mirroring

Answer 8

• 2 hard drives, one backup (slowest)

- whatever is written on one block is copied to the same block on the backup hard drive

Question 9

RAID 5

Parity

Answer 9

3 hdd’s, HOT SWAPPABLE (moderate speed)

-writes to hard drive, but leaves one block open in case of server failure
A / / A
B / B /
/ C / C

Question 10

RAID 10

Answer 10

• 4 HDDs (fast as possible, most expensive) HOT SWAPPABLE
• Raid 0 + Raid 1
• 2 hard drives used to perform raid 0, while the other 2 MIRROR the process

Question 11

Hot Swappable

Answer 11

• a hard drive can be removed or replaced while machine is still running

Question 12

Repository

Answer 12

• the “bag” a server reaches into for new packages when updating a server

Question 13

4 Parts of an Application

Answer 13

1) Front End - webserver (what you can see) APACHE
2) Back End - the database application (MySQL)
3) Config File(s) - where you make changes for an application
4) Log File(s) - keeps track of everything happening (system/app log)

Question 14

User Datagram Protocol

UDP

Answer 14

• TCP alternative
• provides port numbers
• only sends short packets, causing lower latency and bandwidth usage

Question 15

Proc Files

Answer 15

-files in proc directory that can list CPU info about hardware and configurations

/proc/cpuinfo
          meminfo
          version
          scsi/scsi
          partitions

Question 16

Manifest

Answer 16

-a script

Question 17

Switch

Answer 17

-a device that filters and forwards packets between LAN segments

Question 18

Lightweight Directory Access Protocol

LDAP

Answer 18

• authenticates all users to be controlled from one server (and secures network)
• Port 389, 636

$Config: /etc/ldap/slapd (in directory)
$Log: /var/log/messages

Install: yum install openldap openldap-clients openldap-servers

Control: service openldap start/stop/restart

Question 19

Network File System

NFS

Answer 19

• find all files in an environment in one place
• Port 111, 2049

$Config: /etc/exports
$Log: /var/nfs/nfslog

Install: yum install nfs-utils nfs-utils-lib
Control: service nfs start/stop/restart
rpcbind

Question 20

Router

Answer 20

• forwards data packets along networks

- connected to at least 2 networks (LANS or WLANS) at the gateway