2.2 Given a scenario, configure servers to use network infrastructure services.

📘CompTIA Server+ (SK0-005)

IP configuration is one of the most important tasks when setting up a server. A server must communicate properly on the network to provide services such as file sharing, web hosting, authentication, email, virtualization, and database services.

If IP settings are wrong, the server will not be reachable by users, other servers, or network devices.

This section explains everything you need to know for the Server+ exam in clear and simple language.

1. What Is IP Configuration?

IP configuration is the process of assigning network settings to a server so it can communicate with other devices.

Every server connected to a network must have:

IP address
Subnet mask (or prefix length)
Default gateway
DNS server address

These settings allow the server to:

Communicate inside its local network
Communicate outside its network (internet or other networks)
Resolve domain names into IP addresses

2. IPv4 Addressing

Most enterprise networks still use IPv4.

An IPv4 address:

Is 32 bits
Written in dotted decimal format
Example format: 192.168.10.25

It consists of:

Network portion
Host portion

The subnet mask determines which part identifies the network and which part identifies the host.

2.1 Public vs Private IP Addresses

Private IP Addresses

Used inside internal networks (not directly reachable from the internet).

Private IP ranges:

10.0.0.0 – 10.255.255.255
172.16.0.0 – 172.31.255.255
192.168.0.0 – 192.168.255.255

Servers in internal environments (file servers, domain controllers, database servers) usually use private IP addresses.

Public IP Addresses

Routable on the internet
Assigned by an ISP
Used for public-facing servers (web servers, mail servers)

3. IPv6 Addressing

IPv6 is the newer IP version designed to replace IPv4.

IPv6:

128 bits
Written in hexadecimal
Example format: 2001:0db8:85a3:0000:0000:8a2e:0370:7334

Important points for the exam:

Provides a very large number of IP addresses
No need for NAT in most cases
Supports auto-configuration

Common IPv6 types:

Global Unicast (public equivalent)
Link-local (automatically assigned, starts with FE80)
Unique local (private equivalent)

Servers in modern environments may use both IPv4 and IPv6 (dual stack).

4. Static vs Dynamic IP Configuration

This is a very important exam topic.

4.1 Static IP Address

A static IP is manually configured.

Used for:

File servers
Web servers
DNS servers
Domain controllers
Virtualization hosts
Backup servers

Why static IP for servers?

The IP address must not change.
Clients and services depend on a consistent address.
DNS records point to fixed IPs.

Advantages:

Predictable
Stable
Required for infrastructure services

Disadvantages:

Must be manually managed
Risk of IP conflicts if poorly documented

4.2 Dynamic IP Address (DHCP)

A dynamic IP is assigned automatically by a DHCP server.

DHCP = Dynamic Host Configuration Protocol

Used for:

Workstations
Temporary systems
Lab environments

Servers usually should NOT rely on dynamic addressing unless using DHCP reservation.

4.3 DHCP Reservation

DHCP reservation:

DHCP assigns the same IP address every time to a specific MAC address.
Combines central management with consistency.

Used in:

Managed enterprise networks
Virtualized environments

The exam may test when to use:

Static configuration
DHCP
DHCP reservation

5. Subnet Mask / Prefix Length

The subnet mask defines:

Which part of the IP is the network
Which part identifies the host

Example:

255.255.255.0 = /24

CIDR notation:

Smaller subnet:

Fewer hosts
More network segmentation

Larger subnet:

More hosts
Less segmentation

Servers in secure environments may be placed in separate VLANs or subnets for security and traffic control.

6. Default Gateway

The default gateway:

Is the router’s IP address
Allows communication outside the local subnet

If default gateway is missing or incorrect:

Server can communicate locally
But cannot reach external networks

For example:

Server cannot access cloud backup
Cannot reach update servers
Cannot connect to external APIs

7. DNS Configuration

DNS = Domain Name System

DNS translates:

Hostnames → IP addresses

Example:

Internal services rely on DNS
Active Directory depends heavily on DNS

Servers must have correct DNS settings:

Internal DNS server for domain environments
External DNS for public services

Incorrect DNS causes:

Login failures
Service communication failures
Application errors

8. NIC Configuration (Network Interface Card)

A server may have:

One NIC
Multiple NICs

Multiple NICs are used for:

Redundancy
Network separation
Management network
Storage network (iSCSI)
Backup network

Important concepts:

NIC Teaming (Bonding)

Combines multiple NICs
Provides redundancy and load balancing

If one NIC fails:

Traffic continues through another NIC

9. VLAN Configuration

VLAN = Virtual LAN

Servers may be assigned to specific VLANs:

Management VLAN
Production VLAN
Storage VLAN
DMZ

IP configuration must match the VLAN subnet.

If VLAN and IP do not match:

Communication will fail.

10. APIPA (Automatic Private IP Addressing)

APIPA range:

169.254.0.0 – 169.254.255.255

If a server shows an IP starting with 169.254:

DHCP failed
Server cannot reach proper network

This is an important troubleshooting point for the exam.

11. NAT (Network Address Translation)

NAT allows:

Private IP addresses to communicate with public networks

Used in:

Edge routers
Firewalls

Public servers may use:

Static NAT
Port forwarding

Server administrators must understand:

Internal IP vs external IP
Port mapping

12. IP Configuration in Virtualized Environments

In virtual environments:

Each virtual machine:

Has its own virtual NIC
Requires IP configuration

Virtual switches:

Connect VMs to networks
May support VLAN tagging

Host server:

Also requires correct IP configuration

13. Common IP Configuration Mistakes (Exam Focus)

You should know how to identify these:

Wrong subnet mask
Duplicate IP address
Wrong default gateway
Incorrect DNS server
VLAN mismatch
Disabled NIC
DHCP not reachable
Firewall blocking traffic

14. Basic Troubleshooting Commands (General Knowledge)

Even though Server+ is not command-heavy, know these basic tools:

ipconfig / ifconfig
ping
tracert / traceroute
nslookup
netstat

These help verify:

IP assignment
Gateway reachability
DNS resolution
Open connections

15. Documentation and IP Address Management (IPAM)

Enterprise environments use:

IPAM = IP Address Management

Used to:

Track IP addresses
Prevent conflicts
Manage subnets
Document network structure

Servers must be documented properly:

IP address
MAC address
VLAN
DNS entries
Purpose

This is important for change management and disaster recovery.

16. Security Considerations

When configuring IP:

Disable unused NICs
Use separate management network
Avoid exposing internal IPs publicly
Use firewalls
Use access control lists (ACLs)
Segment networks properly

Public-facing servers:

Often placed in a DMZ

DMZ = Demilitarized Zone
Separate network segment for external services.

17. Key Exam Comparison Points

Be ready to compare:

Concept	Know This
Static vs DHCP	Servers usually need static
IPv4 vs IPv6	Address length and format
Private vs Public IP	Internal vs Internet
APIPA	DHCP failure
DNS vs IP	Name resolution
Default Gateway	Access outside subnet
NIC Teaming	Redundancy & load balancing
VLAN	Logical network segmentation

Final Exam Tips

For the Server+ exam:

Servers providing infrastructure services require static IPs.
DNS configuration is critical for domain environments.
Incorrect subnet mask is a common exam trick.
APIPA means DHCP failure.
Always check gateway and DNS when troubleshooting.
Understand IP configuration in virtualized and multi-NIC environments.
Know when to use DHCP reservation.

Summary

IP configuration ensures a server can:

Communicate on the network
Reach other servers
Access external services
Provide services reliably

It includes:

IP address
Subnet mask
Default gateway
DNS
VLAN settings
NIC configuration
Static vs dynamic assignment

Understanding these concepts clearly will help you confidently answer Server+ SK0-005 exam questions related to network infrastructure services.