Root Cause Analysis

Know WHY your site went down — not just that it did

Most monitoring tools tell you something is broken. PulseStack™ tells you exactly what broke, why, and how to fix it — by connecting to your server and running real diagnostic checks.

Root Cause Analysis
api.example.com
Down

The problem with traditional monitoring

Every monitoring tool can tell you a site is down. Almost none of them tell you why.

Alert: Your site is down!

You get a notification. Something is broken. But what? You have no idea. Time to start guessing.

Generic advice: Check your logs

Helpful, right? SSH in, grep through files, hope you find something relevant in thousands of lines.

Hours of manual debugging

Is it DNS? Memory? Disk space? SSL? You check each one manually while your site stays down and users leave.

What PulseStack™ does instead

Automatic root cause diagnosis

The moment downtime is detected, PulseStack™ SSH-connects to your server and runs all 12 diagnostic checks in parallel. Within seconds, you have the exact cause, affected services, and terminal commands to fix it. No guessing, no manual investigation, no wasted time.

12 Diagnostic Checks

Every check that runs when your site goes down

Not one check. Not three. Twelve independent diagnostics run in parallel on your server to find the root cause in seconds.

01

HTTP Response Check

Tests the URL directly from our servers to verify HTTP status code and response time.

02

DNS Resolution

Verifies DNS records resolve correctly and checks for propagation issues across nameservers.

03

SSL Certificate

Checks certificate validity, expiration date, and chain trust for HTTPS connections.

04

Port 443 (HTTPS)

Verifies the HTTPS port is open, listening, and accepting TCP connections on the server.

05

Port 80 (HTTP)

Verifies the HTTP port is accessible and responding to incoming connection requests.

06

Nginx/Apache Status

Checks if the web server process is running and reports its current operational state.

07

Nginx/Apache Config Test

Validates the web server configuration syntax to detect misconfigurations causing failures.

08

Disk Usage

Checks all disk partitions for space issues that can cause write failures and crashes.

09

Memory Usage

Checks RAM and swap usage to detect memory exhaustion causing OOM kills and slowdowns.

10

System Load

Evaluates CPU load averages against core count to identify processing bottlenecks.

11

Recent Error Logs

Searches system and application logs for recent errors, warnings, and crash traces.

12

Listening Services

Audits all processes listening on network ports to detect crashed or hung services.

How it works

From detection to diagnosis in seconds. Fully automated, zero manual work.

Step 01

Monitor detects downtime

Your HTTP, port, or keyword check fails. PulseStack™ confirms the outage from multiple global locations to rule out false positives.

Step 02

We connect to your server

Via SSH or our lightweight agent, PulseStack™ runs all 12 diagnostic checks in parallel directly on your server. Real commands, real output.

Step 03

You get the diagnosis

The exact root cause is identified and presented with context and fix commands. Your team can resolve the issue in minutes, not hours.

Real-world diagnoses from PulseStack™

These are the kinds of problems our root cause analysis catches every day. Real symptoms, real causes, real fixes.

503 Service Unavailable
Critical
Root Cause
Memory Exhaustion

Server RAM at 92%. PHP-FPM workers consuming all available memory, causing nginx upstream timeouts.

Fix Applied
$sudo systemctl restart php8.1-fpm && sudo sysctl -w vm.swappiness=60
500 Internal Server Error
Critical
Root Cause
Disk Full

/var/log partition at 100%. Application unable to write temp files or session data, crashing on every request.

Fix Applied
$sudo journalctl --vacuum-size=500M && sudo find /var/log -name '*.gz' -delete
HTTPS Connection Failed
Warning
Root Cause
SSL Certificate Expired

Certificate expired 2 days ago. Browser and bot traffic both affected. Auto-renewal failed due to DNS challenge.

Fix Applied
$sudo certbot renew --force-renewal && sudo systemctl reload nginx
Intermittent Timeouts
Warning
Root Cause
DNS Propagation Incomplete

DNS records updated 4 hours ago but 2 of 6 nameservers still returning old IP address. ~33% of requests failing.

Fix Applied
$Wait for full propagation (TTL: 3600s) or flush DNS cache on remaining nameservers

A better way to handle downtime

Without PulseStack™

1
Get alert: site is down0 min
2
SSH into server manually5 min
3
Check logs, disk, memory one by one15 min
4
Google the error messages25 min
5
Try different fixes40 min
6
Hope it works60 min
Average resolution time~60 minutes

With PulseStack™

Alert: site is down0 min
12 diagnostics run automatically0.5 min
Root cause identified1 min
Fix command provided1 min
Problem resolved3 min
Average resolution time~3 minutes

That's a 20x faster resolution time. Every minute of downtime costs money.

Available on Pro and above

Root Cause Analysis is included with Pro plans and above. Server Diagnostics (required for root cause analysis) is available on Team plans and above.

Pro
£29/mo
Root Cause Analysis
Recommended
Team
£49/mo
+ Server Diagnostics
View all pricing plans
PulseStack™
Monitoring
Incidents
Status pages
Maintenance
Team members
Integrations & API
example.com
HTTP/S monitor · Checked every 2 min
Current status
Up
Currently up for 5d 14h
Last check
26 seconds ago
Checked every 2 min
Last 24 hours
100%
Domain & SSL cert.
Valid
Expires 12/03/2026
Last 7 days
100%
0 incidents, 0 m down
Last 30 days
99.999%
1 incident, 12 m down
Avg. response
101.66 ms
Min: 16.76 ms
Response timeLast 30 days
Feb 3, '26Feb 17, '26Mar 3, '26
Average
101.66 ms
Minimum
16.76 ms
Maximum
1,546.96 ms
4.7
stars out of 5
265+
reviews on G

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