You can’t migrate what you don’t know exists
Why Discovery/Documentation is important:
Discovery eliminates unknowns by mapping every device, connection, and dependency across your infrastructure. It reveals the overlooked details that can derail projects, like an unmanaged switch supporting critical operations or a legacy system with no clear owner.
Documenting the requirements gathered during the discovery phase of the Network Migration and Tech Refresh Project will serve as a foundational reference to any successful migration and technology refresh.
Network Infrastructure Audit Checklist
Network Devices & Inventory
|
Attribute |
Details |
|
Device Roles |
Categorized into: Switches (Core, Distribution, Access), Routers (Edge, Branch), Firewalls (Perimeter, Internal), Wireless Controllers, Load Balancers |
|
Make & Model |
Manufacturer details and model numbers (e.g., Cisco Catalyst 9300, Palo Alto PA-3220, FortiGate 100F, Juniper EX3400) |
|
OS / Firmware |
Software version, build number, release notes cross-checked for compatibility and known vulnerabilities/bugs |
|
Uptime & Last Reboot |
Indicates device health and operational stability; correlated with config changes or outages |
|
Location & Rack Info |
Data center/branch location, building, floor, room, rack unit (RU), cabinet IDs |
|
Labeling & Asset Tagging |
Hostname labels, asset IDs, tag readability, and accuracy with CMDB or tracking sheet |
|
Configuration Backup |
Manual/automated (RANCID, Oxidized, Git, SolarWinds); schedule, backup location, and verification checks |
|
Running Configuration |
Versioned storage, access control, and alignment with last approved change request |
|
Serial Numbers & Licensing |
Serial numbers recorded and mapped to support contracts or smart licensing platforms |
|
Power Feeds & Redundancy |
UPS, PDU info, dual power supply check, circuit details, and failover readiness |
|
Port & Interface Inventory |
Interface counts, speeds (1G/10G/40G/100G), uplink types, unused ports |
|
Hardware Modules |
SFPs/GBICs, line cards, stacking cables, netflow/telemetry support cards |
|
Photos |
Front and rear photos of each device (including LED status, cabling, ports, power supplies) |
|
Documentation Status |
Rack elevation diagrams, wiring maps, device IP plan, and Layer 1/2/3 maps linked |
|
Monitoring Status |
Confirm SNMP setup, polling intervals, alert thresholds configured in monitoring tools |
|
End-of-Life/End-of-Support |
Lifecycle reports from vendor portals with refresh plan and risk matrix |
|
Notes & Observations |
Physical cleanliness, cabling hygiene, noise/temperature issues, field engineer feedback |
Physical Location
|
Item |
Details |
|
Rack Unit |
Location, room, building ID |
|
Photos & Labels |
Front/back photos, LEDs, cable labeling |
|
Power |
UPS, grounding, source validation |
Configuration Backup Strategy
|
Item |
Details |
|
Backup Method |
Manual/Automated via RANCID, Oxidized, Git, etc. |
|
Frequency |
Daily, weekly, on-change |
|
Storage Location |
On-prem/cloud, version-controlled |
|
Config Review |
Misalignment checks across NTP, SNMP, AAA, ACLs |
Lifecycle and End-of-Support
|
Item |
Details |
|
Lifecycle Check |
Vendor support status |
|
Replacement Plan |
Devices flagged for refresh |
|
Contract Impact |
Patch/feature availability, warranties |
Security Configuration Review
|
Item |
Details |
|
Access Controls |
Console, SSH, Telnet settings |
|
Passwords |
Encryption types (Type 5, 9) |
|
VTY Lines |
Access from management subnets only? |
|
SNMP |
v2c vs v3, community strings/keys |
Licensing & Feature Activation
|
Item |
Details |
|
License Type |
Traditional vs Smart |
|
Feature Sets |
VPN, routing, SD-WAN, etc. |
|
Subscription Expiry |
Dates for firewalls, controllers, etc. |
High Availability & Redundancy
|
Item |
Details |
|
Stacking |
StackWise, Virtual Chassis |
|
Firewall Failover |
Active/Active or Active/Standby |
|
Redundancy |
Fans, uplinks, PSUs |
|
Gateway Redundancy |
VRRP, HSRP setup |
Configuration Hygiene
|
Item |
Details |
|
Unused Elements |
VLANs, ACLs, interfaces |
|
Policy Conflicts |
Duplicate or overlapping policies |
|
Hostnames |
Naming standardization |
|
System Configs |
Logging, NTP, AAA, DNS, QoS |
|
Banner |
Compliance banners present |
Performance and Health Metrics
|
Item |
Details |
|
Resources |
CPU, memory, temperature trends |
|
Interfaces |
Errors, discards, CRCs, flaps |
|
Routing |
BGP/OSPF flaps, adjacencies |
|
Monitoring Tools |
PRTG, SolarWinds, NetBox history |
VLANs
|
Attribute |
Details |
|
VLAN IDs |
Example: VLAN 10 (Guest WiFi), VLAN 20 (VoIP), VLAN 30 (Corporate WiFi) |
|
Purpose |
Segmentation by function, department, access levels |
|
Subnet Mapping |
VLAN to subnet correlation |
|
Security |
VLAN ACLs, private VLANs for isolation |
|
Spanning Tree |
VLAN-specific root bridge roles and STP settings |
|
Trunking |
Native VLANs, allowed VLANs on trunks |
|
Documentation |
VLAN usage, change history, lifecycle tagging |
Subnets
|
Attribute |
Details |
|
IP Ranges |
CIDR-based definitions per VLAN/site (e.g., 10.10.20.0/24 for VLAN 20) |
|
DHCP Scopes |
DHCP ranges, reserved IPs, exclusions, lease durations, scope utilization %, primary/backup DHCP servers |
|
Static Assignments |
Core infra devices (gateways, servers, printers), documented in IPAM or spreadsheet |
Routing Protocols
|
Protocol |
Key Info |
|
OSPF |
Areas, Router IDs, DR/BDR, Hello/Dead timers, Network Types, Authentication (plain/text or MD5), LSDB summary |
|
BGP |
AS numbers (local/remote), Neighbor relationships, Path attributes (Local Preference, MED, AS Path), Route maps, Prefix lists, Community tags, Route reflectors, Peering via VPN/MPLS |
|
Static Routing |
Used in edge, stub, or DMZ segments |
|
Redistribution |
Between BGP ↔ OSPF or Static ↔ Dynamic, with route filtering and tag management |
IoT & Edge Devices
|
Category |
Attributes |
|
Temp Sensors/HVAC |
Make/model, IPs, VLANs, polling interval, thresholds for alerts, integration with BMS |
|
Cameras/NVRs |
IPs, VLAN, model, storage retention, access control, PoE status, firmware |
|
Printers |
Hostname, IPs, VLAN, print server config, driver/firmware version, user mapping |
|
Access Control |
Biometric/card systems, IPs, controller info, door mapping |
|
UPS Monitoring |
IP-based console access, SNMP integration, battery age, thresholds |
|
Edge Compute |
Raspberry Pi, Industrial PC details, containerized apps, OS version |
|
Monitoring & Alerts |
SNMP, HTTP API, MQTT for sensors, logging and notification mapping |
ISP / Internet
|
Item |
Details |
|
ISP Providers |
Primary, backup providers with service type (Broadband/MPLS/Leased Line) |
|
Account Info |
Circuit IDs, billing accounts, SLAs, escalation matrix |
|
Bandwidth |
Contracted vs actual, burstable limits, usage history, link saturation checks |
|
Last Mile |
Media type (fiber, copper, wireless), demarc location |
|
Public IPs |
IP blocks, NAT mapping, PTR records |
|
Routing |
BGP with ISP, static routes, dual-homing strategy |
|
Outage History |
Major incidents, RCA summaries |
Servers & Services
|
Area |
Details |
|
Physical/Virtual |
Host OS, hypervisor type (VMware/Hyper-V), vCPU/Memory allocation |
|
Patch Status |
OS and app-level patch cadence, automation tools (WSUS, Ansible) |
|
DNS/DHCP |
Server roles, split DNS setup, forward/reverse zone delegation |
|
Directory Services |
AD domain structure, FSMO role holders, trust relationships |
|
Backup Status |
Backup tools (Veeam, Commvault), frequency, restore tests, offsite copies |
|
Antivirus & EDR |
Solution in place, policy applied, update status |
|
Key Services |
LDAP, RADIUS, File/Print, Remote Access, Licensing Servers |
IPsec VPN
|
Attribute |
Details |
|
Peer Endpoints |
Site names, public IPs, DNS names, geo-location |
|
Tunnel Type |
Site-to-site, Remote Access, DMVPN, GRE-over-IPsec |
|
Phase 1 Settings |
Encryption (AES-256), Hashing (SHA-2), DH group, Lifetime |
|
Phase 2 Settings |
Encryption domains, PFS settings, SA lifetimes |
|
Authentication |
PSK, RSA certs, certificate authority info |
|
High Availability |
Primary/backup peer config, Dead Peer Detection |
|
Logs & Monitoring |
Tunnel status, uptime, logs, SNMP/NetFlow integration |
|
Vendor Contacts |
SLA, after-hours support, portal credentials |
VoIP Systems
|
Item |
Details |
|
Call Manager |
Physical/Virtual, Version |
|
QoS |
DSCP EF, VLAN 20, Jitter Buffer |
|
SIP |
Trunks, URI, Phone models |
WiFi / Wireless
|
Attribute |
Details |
|
SSIDs |
Broadcast/non-broadcast, VLANs mapped |
|
Auth Type |
WPA2/WPA3 Personal vs Enterprise, RADIUS/NPS integration |
|
AP Details |
Make/model, firmware, mounted location, PoE consumption |
|
Controller Info |
On-prem/cloud-managed (e.g., Meraki, Aruba), redundancy |
|
RF Coverage |
Heatmaps, signal strength thresholds, noise levels |
|
Channel Plan |
2.4GHz (1,6,11), 5GHz/6GHz DFS settings |
|
Band Steering |
Enabled/disabled, client distribution patterns |
|
Wireless QoS |
WMM, VoIP prioritization |
|
Guest Access |
Captive portal, time-based access, isolation policies |
Environmental Sensors
|
Attribute |
Details |
|
Device Info |
Model, location, calibration date |
|
Alert Thresholds |
Warning/critical values for temperature/humidity |
|
Monitoring |
Integration with NMS, polling frequency |
|
Connectivity |
SNMP, HTTP/HTTPS, MQTT |
|
Power |
PoE/non-PoE, backup power status |
|
Logs |
Alert history, environmental trends |
Syslog
|
Item |
Details |
|
Server IP/Port |
E.g., 10.10.10.100:514 or :6514 TLS |
|
Retention |
30d for switches/routers, 1y for firewalls |
SNMP & API Monitoring
|
Device |
Metrics |
Threshold |
|
Core Switches |
CPU, Temp |
>70% CPU (5 min) |
|
Firewalls |
Sessions, VPN tunnels |
>80% table |
|
Routers |
BGP peer, latency |
Peer down = alert |
|
SNMP Version |
v2c or v3 (RO strings, auth users) |
|
API |
Cisco DNA, Meraki |
|
Polling |
1m critical, 5m edge |
Server & App Monitoring
|
Item |
Check |
|
Hardware |
RAID, SMART errors |
|
Services |
DNS, DB, App (e.g., Apache, Exchange) |
|
Rules |
Disk >85%, Apache down, SQL deadlocks |
End User Computing (EUC)
|
Attribute |
Details |
|
Device Types |
Desktops, laptops, thin clients, mobile devices (phones/tablets), BYOD vs. corporate-issued |
|
Operating Systems |
Windows, macOS, Linux, ChromeOS; versions in use, update compliance |
|
Patch Management |
WSUS, Intune, JAMF, SCCM, third-party patch coverage (Adobe, Java) |
|
Endpoint Protection |
Antivirus/EDR agents, real-time protection, last scan date, definition update status |
|
Local Admin Rights |
Control policies, exception tracking, audit logs |
|
User Mapping |
Username-device association, department tagging, AD join status |
|
Software Inventory |
Installed apps list per device, license usage, version tracking |
|
Remote Access Tools |
VPN client, RDP settings, remote desktop agents (e.g., AnyDesk, TeamViewer) |
|
Asset Lifecycle |
Procurement date, warranty/AMC status, refresh cycle plans |
|
Monitoring Agents |
Endpoint telemetry tools (CrowdStrike, Nexthink, SysTrack), performance & health data |
|
Drive Encryption |
BitLocker/FileVault status, key escrow policies |
|
Data Backup |
Folder redirection, cloud sync (OneDrive/Google Drive), endpoint backup tools |
|
Compliance |
DLP policies, USB device control, GDPR/SOX adherence checks |
|
WiFi Usage |
Access point affinity, roaming patterns, WiFi drivers |
|
Support Channels |
Helpdesk system (Jira, Freshservice, ServiceNow), asset tickets linked to user/device |
People & Contacts, Vendors
|
Category |
Details |
|
Internal IT Teams |
Names, phone, email, areas of ownership, shift schedules |
|
On-Site Contacts |
Site engineers, floor managers, weekend support |
|
Escalation Matrix |
L1, L2, L3 contacts for all infrastructure areas |
|
Vendors |
ISP, Firewall, WiFi, Core Switch OEMs – contacts, support contracts |
|
Partner Support |
System integrators, managed service providers, renewal contacts |
|
Incident Contacts |
Security team, compliance, legal advisors for major outages |
Physical Infrastructure Documentation & Evidence
In every infrastructure audit, going beyond configurations and IP mapsis crucial—on-site physical validation adds a level of transparency notpossible with remote tools. This is for hands-and-feet support personnel or engineers on the premises. Their task is to take visual and tactile records of network hardware, cabling, rack configuration, power connections, and environmental parameters.
Every item on this list assists in filling the gap between reality and documentation. These documents are more than pictures—they act as baseline guides for troubleshooting, capacity planning, physical relocations, hardware refreshes, and compliance audits. Correctphotographic and observational documentation can also revealproblems such as inconsistent labeling, obstructed airflow, loadedPDUs, or missing grounding straps—issues that go unnoticed on logical network diagrams.
|
Category |
Checklist / Description |
|
Photographic Documentation |
– Front and rear images of every network device (switches, routers, firewalls, APs, PDUs, etc.) – Zoomed-in shots of serial numbers, model stickers, and licensing labels – LED status indicators showing operational state (green/orange/blinking) |
|
Cabling & Patch Panels |
– Detailed photos of cable paths, color codes, and cable types – Patch panel-to-switch port mapping and label clarity – Fiber trays, splice points, termination enclosures, and tray IDs – Power cabling to PDU, UPS, and device power supplies |
|
Rack Elevation & RU Mapping |
– Front and rear full rack elevation photos – RU allocation diagram (what’s occupying which space) – Identify empty/unused RU slots for planning – Photos showing grounding straps and bonding points |
|
Serials & Asset Tags |
– Cross-check serial numbers against asset list and warranty records – Ensure hostname labels match documented names |
|
Physical Security Measures |
– Cabinet lock type (e.g., tubular, combination), key numbers if applicable – Access control features: biometric readers, keypads, or RFID readers – Presence of tamper-evident seals on core or sensitive devices |
|
Environmental Controls |
– Photos and logs of temperature and humidity gauges – Location and type of fire suppression systems (FM200, Novec, etc.) – Check airflow direction and fan/filter cleanliness |
|
Electrical Circuit Mapping |
– Document every power circuit feeding the rack: panel number, breaker number, breaker rating (A) – Photograph breaker panel labels before making changes |
|
Power Chain Evidence |
– Photograph UPS units, model numbers, and LCD displays – Confirm input/output feeds for UPS and PDU – Record PDU model, port count, and load capacity – Note battery expiry dates for UPS and battery backup units |
|
Grounding & Electrical Verification |
– Ensure all racks are properly grounded – Check for grounding straps between rack, PDU, and cable trays – Capture manufacturer’s grounding instructions if available |
|
Capacity Planning Inputs |
– Note available power headroom (amps, kVA) – Free RU space for expansion – Identify thermal hotspots and power constraints |
|
Vendor Paperwork |
– Store hard copies or scanned copies of: rack layouts, vendor designs, warranty papers, MSA/MSRs, hardware BOMs, and support contracts |
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