The stakes are real. Manufacturing accounted for 71% of the industrial ransomware attacks tracked by Dragos's 2024 report, with industrial ransomware cases climbing 50% from 2022 to 2023.
Periodic vulnerability scans and annual inventories can't keep pace with environments where assets, permissions, and attacker behavior shift daily. This guide covers how to implement continuous IT/OT monitoring safely, when it makes sense, what to prepare beforehand, and the mistakes that trip up most deployments.
Key Takeaways
- Continuous monitoring builds a living view of assets, vulnerabilities, permissions, and adversary activity across IT and OT.
- Safe rollouts start with asset discovery, documented ownership, and OT safety constraints before telemetry begins.
- Alerts must connect to production impact so teams prioritize without disrupting availability or safety.
- NIST, CMMC, and ISA/IEC 62443 requirements convert monitoring data into auditable compliance evidence.
- Anamo consolidates asset visibility, vulnerability data, forensics, and compliance reporting across Windows, Linux, IT, and OT.
How to Secure Manufacturing Environments With Continuous IT/OT Security Monitoring
Step 1: Define the Environment, Owners, and Monitoring Objectives
Before collecting a single packet of telemetry, map the full ecosystem. That means enterprise IT, plant networks, PLCs, SCADA and HMI systems, engineering workstations, virtual machines, remote-access paths, cloud services, and third-party vendor connections.
Next, assign ownership. Someone in security, IT, OT engineering, plant operations, maintenance, or compliance needs to be accountable for each asset group, and everyone needs clarity on:
- Who approves active monitoring versus passive-only collection
- Who signs off on remediation or isolation actions
- Who gets paged for emergency changes during a production run
Define what monitoring needs to achieve, whether that's finding unknown assets, catching unauthorized changes, prioritizing exploitable vulnerabilities, or shortening attacker dwell time. Then set the ground rules: approved collection windows, systems that must never be actively scanned, and escalation paths for any alert touching safety-critical equipment.
NIST's guidance on OT is blunt here: active scanning can destabilize fragile devices and interfere with process state, so NIST's OT security guide recommends extreme caution and offline testing before anything touches production.
Step 2: Discover Assets and Establish a Trustworthy Baseline
You can't protect what you can't see. Build an inventory covering hardware, operating systems, applications, firmware where available, network interfaces, users, services, ports, permissions, and the production processes each asset supports.
A few things to watch for:
- Unmanaged or duplicated assets with no clear owner
- Unsupported legacy systems still running on the plant floor
- Intermittently connected devices that automated discovery tools miss
Once the inventory exists, baseline what "normal" looks like: typical communication patterns, administrative activity, privileged account use, and expected production cycles. That baseline is what lets later alerts separate routine maintenance from genuinely suspicious behavior.
Correlate IT and OT assets instead of running two separate inventories, and validate everything with plant personnel. Automated tools routinely miss isolated or vendor-maintained equipment that staff know exists but that never shows up on a network scan.
Step 3: Collect and Correlate Security Telemetry Continuously
Match the collection method to the environment. Agent-based collection works well on supported IT systems; sensitive OT segments usually call for passive network observation or carefully scoped authenticated checks.
Monitoring should go well beyond network traffic. Track:
- Asset changes and newly exposed services
- CVE vulnerabilities and missing updates
- Insecure configurations and unexpected software
- Authentication events, privilege changes, and remote access
- Changes to production-related files or parameters
Anamo's CDM-SIEM platform handles much of this collection autonomously, capturing UUIDs, system and host details, users, groups, ports, permissions, software and package inventories, and CVE data without manual data entry. Its Comparative HashID Analytics compare system state over time to flag unauthorized changes, with detection often happening within seconds rather than during the next scheduled scan.
Centralize the findings so analysts can see relationships between an asset, its owner, its production role, and any adversary activity tied to it. Route alerts through dashboards and severity-based notification workflows so the right owner sees the right alert, without flooding operators with duplicate noise.
Step 4: Prioritize, Investigate, Remediate, and Verify
Severity alone is a poor prioritization tool. Rank findings by exploitability, asset criticality, exposure, safety and availability impact, privilege level, and whether there's evidence of active adversary behavior.
When investigating suspicious activity, link technical indicators to a timeline: user and permission changes, affected hosts, network paths, and software details. Mapping findings to MITRE ATT&CK for ICS techniques (such as Modify Program, T0889 or Manipulation of Control, T0831) gives investigators a shared vocabulary grounded in real-world industrial attacks.
Pick an OT-safe remediation path:
- Patch during an approved maintenance window
- Remove unnecessary access or disable an exposed service
- Isolate a network segment if the risk is severe
- Apply compensating controls when immediate patching isn't possible
After remediation, verify it actually worked. Recheck the affected control, confirm the change with the system owner, document any residual risk, and update the baseline. This is where Anamo's audit-ready exports matter for regulated manufacturers: they provide chain-of-custody evidence that remediation happened and that it held.
When Continuous Monitoring Is Appropriate and What It Requires
Continuous IT/OT monitoring delivers the most value when any of these describe your plant:
- Converged IT/OT networks
- Legacy plant equipment
- Multiple facilities
- Remote vendor maintenance
- Regulated operations
- Thin security staffing
If any of those apply, periodic scans are already leaving gaps.
Extra caution is warranted with fragile legacy controllers, safety-critical systems, vendor support restrictions, or intermittent connectivity. In those cases, passive or staged collection protects uptime.
Monitoring is not a replacement for segmentation, identity management, secure configuration, patch governance, backups, or incident response. It is the visibility layer that tells you whether those controls are actually working.
Equipment and System Requirements
A capable platform needs:
- Asset discovery across IT and OT
- Windows and Linux support
- Vulnerability and software intelligence
- Permission and user visibility
- Dashboards, alerting, and reporting with role-based access
- Integration with existing ticketing and security workflows
Inputs, Materials, or Conditions
Before deployment, gather:
- Current network diagrams and asset lists
- Criticality ratings and production dependencies
- Approved maintenance windows
- Vulnerability policies and incident procedures
- Vendor contacts
Skill, Safety, or Compliance Readiness
Monitoring requires buy-in from security, IT, OT engineering, plant operations, safety, legal, and compliance teams.
Before anyone enables automated remediation:
- Document approvals across those teams
- Test the monitoring scope in a non-disruptive mode first
- Define escalation paths
Key Parameters That Affect Continuous Monitoring Results
More telemetry doesn't automatically mean better security. Results depend on coverage, context, collection safety, and whether the organization can actually act on what it finds.
| Parameter | Why It Matters | What to Track |
|---|---|---|
| Asset coverage & inventory accuracy | Unknown or misclassified assets create blind spots and skew risk scores | Percentage of in-scope assets reporting current data, age of last observation, ownership gaps |
| Collection method & frequency | IT tolerates frequent agent-based checks; OT often needs passive observation | How frequency affects freshness, system load, and alert timeliness by asset type |
| Contextual risk prioritization | A severe flaw on an isolated, redundant asset isn't the same risk as a minor one on a production-critical workstation | Exploitability, exposure, privilege level, compensating controls, evidence of active exploitation |
| Alert quality & response workflow | Duplicate or context-free alerts cause fatigue and delay real investigations | Deduplication rates, time to triage, false-positive patterns, percentage of alerts with a documented outcome |
| Change tracking & baseline maintenance | Legitimate maintenance can look identical to malicious activity without an updated baseline | Approved change tickets, maintenance windows, and permissions tied back to monitoring alerts |
Industry data on OT response timing is still limited, but the available figures are useful. The SANS 2024 ICS/OT survey found only about 25% of respondents detected a compromise within 6 hours, with another 27% detecting within 6-24 hours.
Containment-to-remediation times trailed similarly. Treat these as general benchmarks, not guarantees. Staffing, telemetry integration, and device compatibility all shift the numbers.
Common Mistakes, Troubleshooting, and Alternatives
Most monitoring failures trace back to a handful of avoidable errors.
- Skipping preparation. Connecting tools without a defined asset scope, OT safety review, or rollback plan leads to missing data. Check network reachability, credentials, agent status, and vendor restrictions before assuming a deployment failed.
- Treating IT and OT identically. Aggressive scanning or automated isolation that's fine for a corporate laptop can knock a PLC offline. Coordinate with operations before any change touches production infrastructure.
- Alert overload. Stale or excessive alerts usually mean the collection frequency, severity thresholds, or deduplication rules need adjusting. Validate findings against plant knowledge and approved change records before escalating further.
- Ignoring early warning signs. Unexpected privileged access, new services, or unexplained process changes deserve investigation every time, not just when they repeat. Document containment, recovery, and residual risk.
Alternatives and complementary tools
Point tools still have a place alongside continuous monitoring:
- OT network-monitoring platforms for deep protocol visibility
- EDR tools for specialized endpoint coverage
- SIEM/SOAR platforms for broader correlation
- Managed security services when internal staffing is thin
Each option trades off deployment complexity, data retention, and cost. A unified platform like Anamo reduces that complexity by combining SIEM, EDR, attack surface monitoring, and vulnerability scanning in one interface instead of stitching together four separate tools.
Conclusion
Continuous IT/OT monitoring works when manufacturers understand their assets, owners, and operational constraints first, then collect data in ways that respect plant safety and availability. Most failures come down to incomplete inventories, unsafe collection methods, alert fatigue, or remediation that ignores production reality.
Success depends on balancing visibility, uptime, risk reduction, and audit evidence. Manufacturers evaluating a consolidated approach can compare Anamo's Continuous Diagnostics and Mitigation (CDM) capabilities against their own IT, OT, and compliance requirements to identify remaining gaps.
Frequently Asked Questions
What is a secure system?
A secure system protects confidentiality, integrity, availability, safety, and authorized use through layered controls, continuous monitoring, access governance, and tested response processes. Security is an ongoing condition, not a one-time configuration.
What are secure boot mechanisms?
Secure boot mechanisms verify the authenticity and integrity of firmware, bootloaders, and OS components before they execute, blocking anything that doesn't match authorized signatures. On industrial systems, confirm vendor support and OT compatibility before enabling them, since some legacy controllers don't handle it well.
What is secure software development?
Secure software development integrates threat modeling, secure design, code review, dependency management, and ongoing monitoring throughout the software lifecycle. For manufacturing, this applies directly to engineering tools, HMI software, and any custom applications running on plant systems.
