Troubleshooting "Request Rejected" Response

Troubleshooting "Request Rejected" Response

Troubleshooting

Troubleshooting “Request Rejected” Response

Find out which security or network component is blocking requests before they reach the Cloudmon application, and what to do about it.

Overview

Cloudmon requests may sometimes return a “Request Rejected” response instead of the expected application response. A typical response looks like this:

Request Rejected
The requested URL was rejected.
Please consult with your administrator.

Your support ID is: <support-id>

This generally means the request was blocked by an upstream security or network component, such as a Web Application Firewall (WAF), reverse proxy, load balancer, or security gateway, before it reached the Cloudmon application.

Where the Request Gets Blocked

The exact components vary by deployment, but a request generally travels through the path below. A “Request Rejected” page means the request was stopped at one of the highlighted components.

Client / Cloudmon Component
➜
Firewall
➜
WAF / Reverse Proxy
➜
Load Balancer
➜
Cloudmon Application

Amber = components that can reject a request. Blue = the Cloudmon application, which is never reached when a request is rejected upstream.

Possible Causes

A request may be rejected due to any of the following:

  • WAF security rules or policies
  • URL or API path restrictions
  • HTTP method restrictions
  • Request headers being blocked or modified
  • Request size or content restrictions
  • IP address or source restrictions
  • Reverse proxy or load balancer configuration
  • Firewall or access-control rules
  • Security policies detecting the request as potentially malicious

Troubleshooting

Work through these steps in order to locate the component that is rejecting the request.

1

  Verify the Request URL

  Confirm that the URL being accessed is correct and that the request is being sent to the expected Cloudmon endpoint.

2

  Check Network Connectivity

  Verify that the affected system can reach the Cloudmon endpoint:

curl -vk https://<cloudmon-url>

Also verify DNS resolution using either command:

nslookup <cloudmon-domain>
dig <cloudmon-domain>
3

  Check the WAF Logs

If Cloudmon is accessed through a WAF, ask the network/security administrator to check the WAF logs for the time of the failed request.

If the response shows a Support ID, give it to the administrator. It identifies the request and the security rule that caused the rejection.

Example:  Your support ID is: 89261xxxx49401xxx5
4

  Check Reverse Proxy or Load Balancer Configuration

  If the request passes through a reverse proxy or load balancer, verify that:

  • The required URL/API path is allowed.
  • The required HTTP methods are permitted.
  • Required headers are forwarded correctly.
  • Request size limits are not being exceeded.
  • No URL filtering or security policy is blocking the request.
5

  Check Firewall and Access-Control Rules

  Verify that the source system is permitted to communicate with the Cloudmon endpoint through the complete network path shown in the diagram above, from the client or Cloudmon component, through the firewall, WAF/reverse proxy, and load balancer, to the Cloudmon application.

6

  Retry the Request

  After the relevant network or security configuration has been reviewed and corrected, retry the failed operation. If the request is no longer blocked, the expected Cloudmon response is returned.

Information to Collect for Support

If the issue persists, gather the following before contacting Cloudmon Support:

About the failure
☐ Cloudmon version
☐ Affected component or feature
☐ URL/endpoint being accessed
☐ Date and time of the failure
☐ Source IP address
☐ Complete “Request Rejected” response
About the environment
☐ WAF / reverse proxy / load balancer details
☐ Relevant WAF or security logs
☐ Network topology, if available