DNS
Is an Internet service that translates domain names into IP addresses and vice-versa.
Location: %SystemRoot%\\System32\\DNS
Class Full IP Address – There are five classes:
1. Class A – 0 – 126 (127 is reserved for Loopback)
2. Class B – 128 – 191
3. Class C – 192 – 223
4. Class D – 224 – 239
5. Class E – 240 – 255
DNS requirements: DC or member server or standalone server with Static IP address.
Does DNS work on a pull basic: when changes are made, the DNS server notifies other servers that changes are available.
What 2 containers are created when DNS is integrated with AD: forestDNSzone and domainDNSzone
Start of Authority (SOA): Specifies the DNS server in charge of a zone.
NS Nameserver:
A Record:
PTR Record:
TXT Record:
CNAME:
MX Record:
DNS Refresh Interval – 15 Minutes
Retry Interval – 10 Minutes
Expires after – 1 day
Minimum Default TTL – 1 Hour
Root hints do? Provide a link between DNS servers and top-level DNS servers
How does Dynamic DNS (DDNS) differ from standard DNS? DDNS allows real-time DNS updates
How is DNS information replicated in DDNS? Through Active Directory
How was DNS information replicated in standard DNS? Through manual copies of the zone file
What two name resolution technologies does DDNS cover? DNS and WINS
When does DDNS update the record? When a client leases an IP address
Common DHCP Options
| Option | Description |
|---|---|
| 006 DNSServers | Specifies the IP address of the DNS servers available to clients on the network. |
| 015 DNSDomain Name | Specifies the DNS domain name used for client resolutions. |
| 003 Router | Specifies the IP address of the router or default gateway. |
| 044 WINS/NBNS Servers | Specifies the IP address of the WINS servers on the network available to clients. |
| 046 WINS/NBT Node Type | Specifies the name resolution type. The available options include 1 = B-node (broadcast), 2 = P-node (peer), 4 = M-node (mixed), and 8 = H-node (hybrid). |
What is secure DNS? A DNS system where updates occur over a secure channel, prevents poison entries, and It is set up automatically.
How does secure DNS work? When a DNS transfer is initiated, the DNS server verifies that the DNS server sending the update is on an approved list.
How can repopulation be forced if a Forward Lookup Zone does not appear in AD? Use net stop logon and net start logon
At what 3 times are Reverse Lookup Zones populated? When IP addresses are leased, when machines are restarted, when ipconfig /registerdns is executed.