Server Admin I Unit 5 DNS Flashcards

1
Q

single-label name

A

network ID that doesn’t use prefixes or suffixes; commonly the host name

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

HOSTS File

A

static file on each Windows based client that is used for DNS name resolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When to use HOSTS file (4)

A
  • provide single-label name resolution
  • map a hostname to an IP address that is different from the one provided by DNS server.
  • provide name resolution outside of local subnet without DNS server
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Cons to using HOSTS

A
  • requires configuration on each host; impractical outside of small setups
  • query will not be sent to DNS server if mapping is in HOSTS file
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Link-Local Multicast Name Resolution

A

LLMNR

Allows clients to find hosts on local suben without DNS or broadcasts

Windows Server 2008 and Vista

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What kind of name resolution does LLMNR enable (2)

A
  • hostname to IP address

- IP address to hostname

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where does LLMNR operate on the network

A

Link local only (local subnet)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

When is LLMNR used as a default

A

When DNS name resolution fails

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

DNS Suffix Search List

A

used to locate computers with single label names in a domain other than the one your computer is in.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where can DNS Suffix Search List be changed. (2)

A
  • Net Adapter properties

- Best changed in DNS Suffix List using Group Policy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

DNS Devolution

A

Active Directory behavior which allows a client computer from a child namespace to access resources in the parent namespace without the need for a fully qualified domain name (FQDN)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does devolution work

A

tries to append the parent DNS name as it goes up tree until resolved or until the devolution level is hit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

devolution level

A

specifies the # of labels or size of the parent domain where devolution will stop

ex: westsim.com ( 2 labels) corp.westsim.com (3) labels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Global Names Zone

A

Zone in DNS db use for single-label name resolution within a domain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

When is Global Names Zone used (3)

A
  • allow clients to use simple host names without domain information for name resolution
  • allow DNS clients to contact NetBIOS (only hosts without need for a WINS server)
  • allow IPv6 only hosts to contact NetBIOS (IPv6 does not support WINS)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

New Server 2012 traffic reduction functionalities(2)

A
  • LLMNR outbound queries not sent to mobile broadband & VPN devices
  • NetBIOS outbound queries not sent to mobile broadband interfaces
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

New Server 2012 response time reduction functionalties (2)

A
  • LLMNR & NetBIOS queries sent at same time & optimized for IPv4/6 queries
  • LLMNR & NetBIOS queries are sent at same time as DNS queries when a network interface is hijacking DNS names
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Domain Name System

A

DNS

Server is usually used in place of system.

hierarchical distributed db used to translate hostnames to IP address and vice verse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Fully Qualified Domain Name

A

FQDN

includes hostname and all domains back to root.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

root domain (2)

A

the originating domain in a network indicated by a . (dot) at the end of the FQDN

normally not shown in FQDN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

top-level domains

A
  • domain that directly precedes the root domain

- .com, .edu, .gov all are tld examples

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

second-level domains

A
  • domain that directly precedes the top-level domain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

sub level domains

A
  • also called subdomains

- additional domains that directly precede second level or other sub level domains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

forward lookup

A

hostname/FQDN to IP address resolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

reverse lookup

A

IP address to hostname/FQDN address resolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

authoritative server

A

DNS server with full complete copy of database for a particular zone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

referral

A

process by which DNS servers querie one another to solve DNS requests

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

recursion

A

process a DNS server or host uses root name servers & subsequent servers to perform name resolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

iterative

A

DNS server requests information from other DNS servers & maintains responsibility for resolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

delegation

A

DNS server hands responsibility for request to another DNS server

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Location of HOSTS file

A

c:\windows\system32\drivers\etc

32
Q

What to do when a entry cannot be removed from DNS cache.

A

Check to see if entry is listed in HOSTS file; will not erase as long as it exists in HOSTS

33
Q

Client Side DNS Name Resolution (3)

A
  1. Entries in the HOSTS file are preloaded into cache.
  2. Client examines its local DNS cache for IP address
  3. If IP address is not in cache, client sends a DNS request to DNS server
34
Q

Server Side DNS Name Resolution (6)

A
  1. DNS name resolution request is received by DNS server.
  2. DNS server checks its local cache for IP address
  3. If name is not resolved & server is authoritative , DNS server responds using information in zone hosted on its server. Forwards if configured for forwarding or conditional forwarding.
  4. If DNS server cannot forward or if forwarding fails; server uses its root hints file (aka cache.dns)
  5. Root DNS server responds with address of TLD or other DNS server.
  6. DNS server forwards request to higher level DNS server which can respond with variety of IP addresses
35
Q

root hints

A
  • aka cache.dns
  • list of known root DNS servers
  • www.Root-Servers.org
  • forwarding overrules root hints
36
Q

Reverse Lookup Zones

A

IPs to FQDNs/hostnames

  • writes IPs in reverse.
    • 192.168.1.1 &raquo_space;»» 1.168.192 in-addr.arpa
37
Q

Primary Zone (4)

A
  • Zone which contains master copy of zone database
  • Read/Write zone
  • Each zone can have only one primary.
  • Permission to have a copy of a zone should be set in primary zone
38
Q

Secondary Zone (3)

A
  • Read only copy of zone db
  • zone transfers based on serial # of SOA record.
  • zone transfers are always intiated by secondary zone, but can be requested by primary
39
Q

Start of Authority

A
  • SOA record
  • 1st record created for a zone.
  • identifies the zone and primary server for zone
  • SOA serial is incremented counter ; increments whenever a change is made to SOA
  • Includes email address of adminstrator responsible for DNS domain
40
Q

Triggers for Zone Transfers (2)

A
  • Refresh Interval

- DNS notify

41
Q

Refresh Interval

A

Specifies the amount of time between requests for SOA record of primary zone.

42
Q

DNS Notify(2)

A
  • lists servers to be notified

- primary server notifies secondary that a change has been made; secondary then intiates zone transfer.

43
Q

Are Zone Transfers Secure(2)

A
  • No
  • Zone data is stored and transfered as clear text.
  • Use IPSec or Active Directory Integrated Zone to secure
44
Q

Active Directory Integrated Zone(4)

A

ADI

  • DNS Zone contained within a Domain Controller (Active Directory)
  • Multi-master zones
  • Zone data replicated during AD replication
  • Zone transfers are secured with AD encryption automatically
45
Q

Active Directory Scopes (4)

A
  • specifies which DC’s have copies of zone data
  • All DC’s - even if DNS is not running
  • All DC in domain with DNS installed.
  • All DC in forest with DNS installed.
46
Q

Name Server Record(2)

A

NS

  • record identifies all name servers that can do name resolution for the zone
  • contains entries for primary and all secondary servers on zone
47
Q

A Record(3)

A
  • host record
  • forward lookups
  • maps an IPv4 (32) DNS host name to IP address
48
Q

AAAA Record(3)

A
  • Quad- A
  • forward lookups
  • maps IPv6 (128 bit) DNS host name to IP address
49
Q

Pointer Record(5)

A
  • PTR
  • Reverse lookup zone
  • Maps IP address to hostname by pointing to correct (A) or (AAAA) record
  • IPv4 records are created in (in-addr.arpa) namespace
  • IPv6 records are created in in6.arpa
50
Q

in-addr.arpa

A

namespace used to designate IPv4 reverse lookup

51
Q

in6.arpa

A

namespace used to designate IPv6 reverse lookup

52
Q

Canonical Name Record(2)

A
  • CNAME
  • provides aliases to hosts that already have an (A) record
  • enables server to be id’d by a different name in DNS
53
Q

Mail Exchange Record(3)

A
  • MX
  • id’s servers available to receive Simple Mail Transfer Protocol (SMTP)
  • lower priority value = more preferential server
54
Q

Service Locator Record(4)

A
  • SRV
  • indicates resources that perform a particular service
  • allows clients to find services via DNS
  • Windows creates automatically as needed
55
Q

WINS / WINS-R Record(3)

A
  • added to zone when you want DNS to use WINS
  • id’s WIN servers to forward failed DNS requests
  • allows resolution of a reverse query unresolvable by DNS
56
Q

Sender Policy Frameword(4)

A
  • SPF
  • id’s authorized mail servers
  • created using TXT records
  • DNS uses SPF to verify the host sending email is authorized to use DNS names
57
Q

Server Manager Path for Common Records

A
Server Manager>>
    Tools>>
         DNS (Manager)>>
              >>
                  DC>>
                       Rt Click | >> List of Common Records
58
Q

Server Properties Path

A

DNS Manager&raquo_space;
Server»
Properties

59
Q

Interfaces Server Properties

A
  • id’s the IPs DNS will use to listen for DNS queries
60
Q

Forwarders Server Properties

A
  • id’s DNS servers that queries are sent to when locak DNS is not authoritative
61
Q

Root Hints Server Properties

A
  • id’s root servers on the Internet
62
Q

Debug Logging Server Properties

A
  • sets detailed logging parameters for adv. troubleshooting
63
Q

Event Logging Server Properties(2)

A
  • specifies events to be logged

- options: No Events, Errors Only, Errors and Warnings, All Events

64
Q

Monitoring Server Properties (2)

A
  • runs a simple or recursive query against DNS server

- recursive query tests forwarding

65
Q

Security Server Properties

A
  • set permissions for users or groups to modify DNS server.
66
Q

Disable Recursion

A
  • Advanced Server Property

- disables forwarding & local DNS client

67
Q

Enable BIND secondaries

A
  • Advanced Server Property

- allows MS DNS to talk to UNIX DNS

68
Q

Fail on load if bad data

A
  • Advanced Server Property

- prevents zone data from loading if it is bad or corrupt

69
Q

Enable Round Robin

A
  • Advanced Server Property

- enables cycling through records when there are multiple records of same type w/same name

70
Q

Enable netmask ordering

A
  • Advanced Server Property
  • provides requester with record that most closely matches the requester’s IP when there are multiple records of same type w/same name.
71
Q

Secure Cache Against Pollution

A
  • Advanced Server Property

- protects cache by not updating when a request sent to 1 domain results in response from another domain.

72
Q

Enable DNSSEC validation for remote responses.

A
  • Advanced Server Property
  • clients with Win7 & greater
  • allows DBS servers to digitally sign records it sends to clients
  • clients use signature to verify DNS record was not altered in transit
73
Q

Enabling automatic scavenging of stale records

A
  • Advanced Server Property
  • removes records that haven’t been updated within specified period of time.
  • must be set on server and zone
  • uses non-refresh interval and refresh interval
74
Q

non-refresh interval

A
  • time periods where DNS updates are not allowed
  • occurs prior to refresh
  • interval between last record refreshed and earliest time when it can be refreshed again
75
Q

refresh interval

A
  • time period interval at which DNS gets updated
  • occurs after non-refresh
  • refresh starts= records begin getting refreshed
  • refresh ends = DNS scavenges un-refreshed records
  • non-refresh begins anew