What Is Active Directory Monitoring and How Does It Prevent Website Downtime?
Active Directory monitoring tracks authentication, replication, and security events in AD so you can see failures such as logon errors or lockouts (4740) for investigation on the sites that depend on them. Microsoft Sentinel raises alerts from those events as they arrive. It collects Windows Security events from domain controllers through the Azure Monitor Agent.
Domain controllers use LDAP (ports 389 and 636) and Kerberos v5 (port 88) to authenticate a session. Monitoring watches the events and health those services produce.
Integration with web infrastructure flags AD issues that impact user logins. Uptime monitoring checks the HTTP endpoints on their own schedule, next to the AD event analysis. Review the website checks alongside AD events.
Sysadmins deploy active directory monitoring to correlate logon failures with website 401 errors.
How Does Microsoft Sentinel Handle Active Directory Event Log Ingestion?
Microsoft Sentinel ingests AD Security and Directory Service logs through the Azure Monitor Agent, collecting events such as 5136 for directory modifications.
Supported Protocols and Event IDs
Domain controllers authenticate with Kerberos v5 (port 88, default 10-hour ticket lifetime) and answer LDAP on ports 389 and 636. Sentinel does not query these protocols. It ingests the events they produce in the Security log.
Event ID 4624 logs successful logons. Event ID 4740 records account lockouts. Event ID 5136 records directory modifications.
KQL rules can alert on brute-force patterns in AD events. Retention settings control how long the logs remain available.
The Azure Monitor Agent forwards logs to a Log Analytics workspace, and it throttles when ingestion runs ahead of the workspace. Filter down to the Event IDs you actually alert on.
What Pricing Tiers Does Microsoft Sentinel Offer for Active Directory Monitoring?
Microsoft Sentinel's East US list price is $4.30/GB for pay-as-you-go. Commitment tiers start at 100 GB/day for $296 a day ($2.96/GB, about 31% less), and the 5,000 GB/day tier is $11,550 a day ($2.31/GB, about 46% less). Data lake storage is $0.026/GB/month. The first 10 GB/day is free for 31 days after you enable Sentinel. Prices differ by region.
| Pricing Tier | Ingestion Rate (GB/day) | Discount vs pay-as-you-go | East US price |
|---|---|---|---|
| Pay-As-You-Go | Unlimited | 0% | 4.30/GB |
| Commitment (100 GB/day) | 100 | 31% | 2.96/GB |
| Commitment (5,000 GB/day) | 5000 | 46% | 2.31/GB |
Commitment tier pricing starts at 100 GB per day, and a 50 GB/day tier is in public preview. Usage above the tier you pick is billed at that tier's rate. Storage billing depends on the volume retained.
Log Analytics allows a user 200 query requests per 30 seconds and runs a query for up to 10 minutes. The Visual Sentinel vs Pingdom comparison describes their website checks.
How Can Website Operators Integrate Active Directory with Web Infrastructure Monitoring?
Website operators check the AD-backed site alongside the directory, using Visual Sentinel's uptime, performance and SSL checks. New users see their site's first check with no card, then start a 7-day trial (card required) or subscribe from $15/month. Solo includes 10 monitors. Query the website on a schedule you choose so failed logins can be investigated alongside AD events.
API and Protocol Compatibility
Visual Sentinel checks the website's availability. Paid plans start at $15/month after a 7-day trial (card required). The platform checks DNS records on a schedule. Visual checks compare screenshots against a baseline.
Business is $80/month for 60 monitors. Agency is $300/month for 300 monitors. Check website availability alongside directory events. SSL monitoring checks HTTPS certificate validity and expiry.
Performance monitoring measures website performance. DNS monitoring checks website records on a schedule. Review these results alongside directory events.
What Key Metrics Should Sysadmins Track in Active Directory for Authentication Failures?
Sysadmins track logon success (Event ID 4624) and account lockouts (4740). Alert on repeated failed logons or lockouts so you hear about a web auth failure while it is happening. The Azure Monitor Agent collects the events for that analysis.
Performance monitoring tracks site response times for comparison with AD latency. KQL rules can flag repeated failed logons; for example, a team might alert on 20 failed logons per minute.
How Does Azure Monitor Agent Collect Active Directory Data?
The Azure Monitor Agent collects AD events from the domain controller's local Security log, as set in a data collection rule, and sends them to your workspace over HTTPS. It collects the Event IDs for logons, lockouts and modifications without tying you to one AD DS version.
Configuration Steps
The Azure Monitor Agent installs on Windows Server 2022. A data collection rule selects which Security events to send, for example Event IDs 4624, 4740 and 5136.
The agent reads the local Security event log and sends it to the workspace over outbound HTTPS (port 443).
Use website DNS monitoring alongside directory checks. The Azure Monitor Agent has no license fee. Sentinel ingestion in East US is $4.30/GB on pay-as-you-go, and automation, extra retention, and other Azure services are billed on their own meters. This setup pairs DNS checks with directory monitoring.
Add Event ID 4624 to the data collection rule's XPath query to collect successful logons.
What Are the Technical Limits of Active Directory Monitoring Tools in 2026?
Log Analytics lets a user send 200 query requests per 30 seconds, and a single query can run for up to 10 minutes. Visual Sentinel complements this with visual diffs for web-AD hybrid monitoring. Paid plans start at $15/month.
Visual monitoring compares screenshots, which is how an auth error that changes the page gets caught. Review the service terms for any availability commitment. Ingestion slows when a workspace is near its cap.
Sysadmins can partition workspaces and review retention and query limits for their deployment.
How Do Active Directory Monitoring Tools Compare for Sysadmins?
Microsoft Sentinel ingests Windows Security events (East US pay-as-you-go is $4.30/GB). Pingdom and UptimeRobot do not monitor Active Directory. Visual Sentinel adds web layers from $15/month (Solo, 10 monitors) up to $300/month (Agency, 300 monitors). Plans are Solo, Starter, Business, and Agency. This comparison highlights differences between directory and website monitoring tools.
| Entity | Free Tier | Paid price ($/month) | AD Support Level |
|---|---|---|---|
| Microsoft Sentinel | 10 GB/day free for 31 days | 4.30/GB pay-as-you-go (East US) | Event-log ingestion (Windows Security events via Azure Monitor Agent) |
| Visual Sentinel | None | 15 (Solo, 10 monitors) | Website checks |
| Pingdom | None (30-day trial) | 18 monthly, 16.50 annual (10 checks) | No AD monitoring found |
| UptimeRobot | 50 monitors | 46 (Team, 100 monitors) | No AD monitoring found |
Microsoft Sentinel ingests Windows Security events at $2.96/GB on the 100 GB/day commitment tier (East US list price). Pingdom (SolarWinds acquisition) monitors uptime from over 100 locations at $18/month billed monthly ($16.50 billed annually) for 10 checks without AD event logs. UptimeRobot (Team plan) tracks 100 monitors for $46/month ($39 billed annually) and lacks Kerberos checks.
Datadog Infrastructure Enterprise costs $23/host/month billed annually and includes an Active Directory integration for replication, LDAP and Kerberos counters. Site24x7's Web Uptime plan is $9/month billed annually for 25 websites. Site24x7 also offers Active Directory monitoring for domain controllers. The Visual Sentinel vs UptimeRobot comparison describes their website checks.
Better Stack's Responder plan costs $34/month ($29 billed annually) and includes 10 monitors. It is an uptime product, not an Active Directory monitor.
Choose a tool that checks the directory events you need to investigate.
What Role Does Visual Sentinel Play in Active Directory-Web Integration?
Visual Sentinel monitors AD-backed websites for uptime, performance, SSL, DNS, visual changes and content changes. Solo covers 10 monitors from $15/month, with uptime checks every 5 minutes. Checks run on the plan schedule.
Layer-Specific Benefits
The uptime layer checks HTTP responses for AD-dependent websites. The performance layer measures site response times for comparison with directory latency. The SSL layer checks the HTTPS certificate.
The DNS check reads website records on a schedule. Visual regression compares screenshots so you can see an auth failure that changes the page. Content monitoring checks for expected or forbidden text on the page.
The website checker shows whether an AD-backed endpoint is returning 401. Solo is $15/month for 10 monitors. Business is $80/month for 60 monitors. Review website checks alongside directory events.
A 7-day trial (card required) suits a short test. Review the website checks alongside the directory events.
Active directory monitoring tools like Microsoft Sentinel handle core events, but Visual Sentinel adds web-specific layers for complete visibility. Review directory events alongside the website checks. Start with a 7-day trial (card required) or Solo at $15/month for 10 monitors, and scale to Business ($80, 60 monitors) or Agency ($300, 300 monitors).
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What Is Active Directory Monitoring and How Does It Prevent Website Downtime?
Active Directory monitoring tracks authentication, replication and security events so you can investigate logon errors and lockouts (Event ID 4740) on the sites that depend on them. Microsoft Sentinel raises alerts from those events as they arrive.
How Does Microsoft Sentinel Handle Active Directory Event Log Ingestion?
Microsoft Sentinel ingests AD Security and Directory Service logs through the Azure Monitor Agent, collecting events such as 5136 for directory modifications. The agent reads the local Security log. It does not poll LDAP on an interval.
What Pricing Tiers Does Microsoft Sentinel Offer for Active Directory Monitoring?
Microsoft Sentinel's East US list price is $4.30/GB for pay-as-you-go. Commitment tiers start at 100 GB/day for $296 a day ($2.96/GB, about 31% less), and the 5,000 GB/day tier is $11,550 a day ($2.31/GB, about 46% less). Data lake storage is $0.026/GB/month. The first 10 GB/day is free for 31 days after you enable Sentinel. Prices differ by region.
How Can Website Operators Integrate Active Directory with Web Infrastructure Monitoring?
Website operators check the AD-backed site alongside the directory, using Visual Sentinel's uptime, performance and SSL checks. New users see their site's first check with no card, then start a 7-day trial (card required) or subscribe from $15/month. Solo includes 10 monitors.
What Key Metrics Should Sysadmins Track in Active Directory for Authentication Failures?
Track logon success (Event ID 4624) and account lockouts (4740). Alert on repeated failed logons or lockouts so you hear about a web auth failure while it is happening.
How Does Azure Monitor Agent Collect Active Directory Data?
The Azure Monitor Agent collects AD events from the domain controller's local Security log, as set in a data collection rule, and sends them to the workspace over HTTPS. Add Event ID 4624 to the rule's XPath query to collect successful logons.
