Active Directory Network Services documents the configuration settings of Active Directory DNS/DHCP services.
NOTE: Each section contains a note listing the tweaks made to streamline the project on core AD Network configuration suitable for a lab environment.
DNS Configuration
| Setting | Value | Description |
|---|---|---|
| DNS Servers | DC01 - 10.0.3.10 DC02 - 10.0.3.20 |
DC01 is the Primary DNS Server configured with DC02 acting as the secondary DNS server |
| Zone-Type | AD-Integated-Primary Zone | DNS zone settings is stored with the Active Directory database file, allowing multi-master domain replication |
| Dynamic Updates | Secure only | Only domain-joined, authenticated devices can register/update their own DNS records |
| Scavenging | No-refresh interval: 7 days Refresh interval: 7 days |
Automatically cleans up stale records left behind by decommissioned or renamed hosts, keeping the zone accurate |
NOTE: The above DNS configurations are configured onto both forward and reverse lookup zones.
- Forward Lookup Zone -
home.local
| Name | Type | Data | Description |
|---|---|---|---|
| home.local | Name Server (NS) | dc01.home.local | Authoritative name server for the zone - primary DC hosting DNS |
| home.local | Name Server (NS) | dc02.home.local | Authoritative name server for the zone - secondary DC providing DNS redundancy |
| DC01 | Host (A) | 10.0.3.10 | Primary Domain Controller - DNS, authentication, directory services |
| DC02 | Host (A) | 10.0.3.20 | Secondary Domain Controller - DNS/AD replication partner for redundancy |
| FS01 | Host (A) | 10.0.3.50 | File Server - hosts shared drives/departmental file shares |
| WS01 | Host (A) | 10.0.3.109 | Admin Workstation - for remote server administration |
- Reverse Lookup Zone -
3.0.10.in-addr.arpa
| Name | Type | Data | Description |
|---|---|---|---|
| 3.0.10.in-addr.arpa | Start of Authority (SOA) | dc01.home.local | Designates DC01 as the primary authority for this reverse lookup zone, holding the master copy for zone updates |
| 3.0.10.in-addr.arpa | Name Server (NS) | dc01.home.local | Authoritative name server for reverse lookups on this subnet - primary DC |
| 3.0.10.in-addr.arpa | Name Server (NS) | dc02.home.local | Authoritative name server for reverse lookups on this subnet - secondary DC, provides redundancy |
| 10.0.3.10 | PTR | dc01.home.local | Reverse mapping for Primary Domain Controller |
| 10.0.3.20 | PTR | dc02.home.local | Reverse mapping for Secondary Domain Controller |
| 10.0.3.50 | PTR | fs01.home.local | Reverse mapping for File Server |
| 10.0.3.109 | PTR | ws01.home.local | Reverse mapping for Admin Workstation |
NOTE: The lab environment's DNS config prohibits access to internet keeping the network secure as an isolated network. A DNS resolver can be configured to forward public DNS queries over the internet.
DHCP Configuration
- DHCP Scope Range - 10.0.3.100 - 10.0.3.200
- Lease Duration - 8 days
| Name | Value | Description |
|---|---|---|
| Address Pool | 10.0.3.100 - 10.0.3.200 | Range of IP addresses DHCP can lease to clients on this subnet |
| 003 Router | 10.0.3.1 | Default gateway assigned to DHCP clients for routing outside the local subnet |
| 006 DNS Servers | 10.0.3.10, 10.0.3.20 | DNS servers (DC01, DC02) assigned to clients for name resolution |
| 015 DNS Domain Name | home.local | DNS suffix appended to unqualified hostnames for domain name resolution |
- DHCP Failover - DHCP failover configured on DC01 with DC02 as partner server
| Name | Value | Description |
|---|---|---|
| Relationship Name | DC01-DC02-DHCP-Failover | Identifier for this failover partnership, used internally by DHCP to track the relationship |
| Partner Server | dc02.home.local | The DHCP server paired with DC01 to provide scope redundancy |
| Mode | Hot-Standby | DC02 only leases addresses if DC01 becomes unavailable, rather than actively load-balancing (Load-Balance mode splits leasing ~50/50 between both servers) |
| Maximum Client Lead Time | 1 hrs 00 mins | Time DC01 (active) waits before assuming full control of the entire address pool if DC02 (standby) goes offline - prevents duplicate lease conflicts during failover |
| State Switchover Interval | 60 mins | Time before a server automatically transitions to COMMUNICATION-INTERRUPTED state after losing contact with its partner |
| Role of this server | Active (DC01) | DC01 is the primary server actively issuing leases; DC02 is the standby, only issuing leases if DC01 is down |
| Address Reserved for Standby | 10% | Percentage of the scope's address pool reserved exclusively for the standby server to hand out during failover |
NOTE: No DHCP relay is configured in this scenario as the server network and client network subnet are same.