What is the difference between physical and logical diagrams, and what are related documentation types?
Physical Diagrams: Show the physical setup (e.g., cables, racks).
Logical Diagrams: Represent data flow and logical connections (e.g., VLANs, subnets).
Related types:
Rack Diagrams: Equipment placement in racks.
Cable Maps: Physical connections between devices.
Network Diagrams:
Include:
* Layer 1: Physical layout of cables and ports.
* Layer 2: VLANs, switches, and MAC address mapping.
* Layer 3: IP addressing and routing between subnets.
What is included in an asset inventory?
Hardware: Devices like servers and routers.
Software: Applications and OS.
Licensing: Usage rights for software.
Warranty Support: Expiry dates and service coverage.
What are key tools for managing IP and service expectations?
IP Address Management (IPAM): Tracks and allocates IP addresses to avoid conflicts.
Service-Level Agreement (SLA): Defines expected service performance (e.g., uptime, response time).
What is a wireless survey/heat map, and why is it useful?
What are the stages of life-cycle management for IT equipment and software?
End-of-Life (EOL): No longer sold or updated.
End-of-Support (EOS): Vendor stops providing fixes or support.
Software Management: Includes patches, OS updates, and firmware upgrades.
Decommissioning: Safe removal and disposal of outdated equipment.
How does change management work?
What is involved in configuration management?
What is SNMP, and what are its key features?
SNMP (Simple Network Management Protocol): Used to monitor and manage network devices.
Key Features:
* Traps: Notifications sent from devices to alert on issues.
* MIB (Management Information Base): Database of device information.
* Community Strings: Keys for device access.
* Authentication: Ensures secure monitoring in SNMP v3. (Username and password) (password hashes)
Versions:
* v2c: Community-based, limited security.
* v3: Adds encryption and authentication for secure communication.
What are the methods of capturing and analyzing network data?
Flow Data: High-level traffic patterns and statistics; used for anomaly detection and usage analysis.
Packet Capture: Captures detailed packet-level traffic for diagnostics and security analysis.
Port Mirroring: Duplicates traffic from one port to another for analysis, often paired with packet capture.
How are baseline metrics and log aggregation used in monitoring?
Baseline Metrics:
* Establish normal performance levels for comparison.
* Enable anomaly alerting/notification when deviations occur.
Log Aggregation:
* Centralizes device logs for analysis.
* Tools include:
* Syslog Collector: Gathers and stores logs.
* SIEM (Security Information and Event Management): Analyzes logs for security and event correlation.
What is API integration, and how does it assist in monitoring?
What are the key types of network discovery and their uses?
What are the core types of monitoring in network management?
What is RPO?
Recovery Point Objective
* Maximum acceptable amount of data loss during an incident.
* Determines how often backups should be taken.
What is RTO?
Recovery Time Objective
What are MTTR and MTBF, and how do they differ?
Mean Time To Repair: Average time to repair a failed component and restore functionality.
Mean Time Between Failures: Average time a system operates without failure.
What are the types of DR sites, and how do they differ?
Cold Site: Basic infrastructure, no pre-installed equipment; slowest recovery time.
Warm Site: Partial setup with some pre-installed hardware and data; moderate recovery time.
Hot Site: Fully operational replica of the primary site; fastest recovery time.
What are the differences between active-active and active-passive high-availability setups?
Active-Active: All systems are online and share the load, providing seamless failover.
Active-Passive: A secondary system remains idle until the primary system fails, then takes over.
What are common methods for testing disaster recovery plans?
Tabletop Exercises: Simulated scenarios to evaluate response procedures without affecting live systems.
Validation Tests: Full-scale tests to ensure systems and processes function as expected in a real disaster.
What is DHCP, and what are its 6 key components?
Dynamic Host Configuration Protocol (DHCP): Automatically assigns IP addresses and other configuration to devices.
Key Components:
1. Reservations: Fixed IP assignments for specific devices.
1. Scope: Range of IPs available for assignment.
1. Lease Time: Duration a device retains its assigned IP.
1. Options: Additional settings like DNS servers, gateways.
1. Relay/IP Helper: Forwards DHCP requests across subnets.
1. Exclusions: IPs within the scope that are not assigned dynamically.
What is SLAAC, and how does it work?
Stateless Address Autoconfiguration: Allows IPv6 devices to self-configure IP addresses without requiring a DHCP server.
Key Processes:
* NDP (Neighbor Discovery Protocol): Facilitates router advertisements and neighbor discovery in IPv6.
What is the DORA process in DHCP, and how does it work?
The DORA process is the four-step communication sequence used by DHCP to assign IP addresses to devices:
Discover:
* The client broadcasts a message to locate a DHCP server.
* Message: “Is there a DHCP server available?”
Offer:
* The DHCP server responds with an available IP address and configuration details.
* Message: “Here is an IP address you can use.”
Request:
* The client requests to use the offered IP address.
* Message: “I would like to use this IP address.”
Acknowledgment:
* The DHCP server confirms the assignment and finalizes the lease.
* Message: “You can use this IP address.”
What is DNS, and what are its key features?
Domain Name System (DNS): Translates human-readable domain names into IP addresses.
Key Features:
DNSSEC: Adds cryptographic authentication to DNS responses to prevent spoofing.
DNS over HTTPS (DoH) and
DNS over TLS (DoT): Encrypts DNS queries for improved privacy and security.
Record Types:
* A: Maps domain names to IPv4 addresses.
* AAAA: Maps domain names to IPv6 addresses.
* CNAME: Provides an alias for another domain name.
* MX: Directs email to the correct mail server.
* TXT: Contains text data, often for email security (e.g., SPF, DKIM).
* NS: Identifies the authoritative nameservers for a domain.
* PTR: Maps IP addresses to domain names (used for reverse lookups).
What are common time protocols, and what do they do?
NTP (Network Time Protocol): Synchronizes system clocks across devices with millisecond accuracy, ensuring consistent timestamps.
* NTS (Network Time Security): Adds cryptographic security to NTP to prevent spoofing or tampering.
PTP (Precision Time Protocol): Offers sub-microsecond accuracy, crucial for time-sensitive applications like industrial automation and financial trading.