User Guide Functional Overview Requirements Architecture System Installation NetEye Additional Components Installation Setup The neteye Command Director NetEye Self Monitoring Tornado Business Service Monitoring IT Operation Analytics - Telemetry Geo Maps NagVis Audit Log Shutdown Manager Reporting ntopng Visual Monitoring with Alyvix Elastic Stack IT Operations (Command Orchestrator) Asset Management Service Level Management Cyber Threat Intelligence - SATAYO NetEye Update & Upgrade How To NetEye Extension Packs Troubleshooting Security Policy Glossary
module icon Elastic Stack
Overview Architecture Authorization Elasticsearch Overview Enabling El Proxy Sending custom logs to El Proxy Configuration files Commands Elasticsearch Templates and Retentions El Proxy DLQ Blockchain Verification Handling Blockchain Corruptions El Proxy Metrics El Proxy Security El Proxy REST Endpoints Agents Logstash Elastic APM Elastic RUM Log Manager - Deprecated
ntopng Visual Monitoring with Alyvix Elastic Stack IT Operations (Command Orchestrator) Asset Management Service Level Management Cyber Threat Intelligence - SATAYO Introduction to NetEye Monitoring Business Service Monitoring IT Operation Analytics Visualization Network Visibility Log Management & Security Orchestrated Datacenter Shutdown Application Performance Monitoring User Experience Service Management Service Level Management & Reporting Requirements for a Node Cluster Requirements and Best Practices NetEye Satellite Requirements TCP and UDP Ports Requirements Additional Software Installation Introduction Single Node Cluster NetEye Master Master-Satellite Architecture Underlying Operating System Acquiring NetEye ISO Image Installing ISO Image Single Nodes and Satellites Cluster Nodes Configuration of Tenants Satellite Nodes Only Nodes behind a Proxy Additional NetEye Components Single Node Cluster Node Satellites Nodes only Verify if a module is running correctly Accessing the New Module Cluster Satellite Security Identity and Access Management External Identity Providers Configure federated LDAP/AD Emergency Reset of Keycloak Configuration Advanced Configuration Authorization Resources Tuning Advanced Topics Basic Concepts & Usage Advanced Topics Monitoring Environment Templates Monitored Objects Import Monitored Objects Data Fields Deployment Icinga 2 Agents Configuration Baskets Dashboard Monitoring Status VMD Permissions Notifications Jobs API Configuring Icinga Monitoring Retention Policy NetEye Self Monitoring 3b Concepts Collecting Events Add a Filter Node WHERE Conditions Iterating over Event fields Retrieving Payload of an Event Extract Variables Create a Rule Tornado Actions Test your Configuration Export and Import Configuration Example Under the hood Development Retry Strategy Configuration Thread Pool Configuration API Reference Configure a new Business Process Create your first Business Process Node Importing Processes Operators The ITOA Module Configuring User Permissions Telegraf Metrics in NetEye Telegraf Configuration Telegraf on Monitored Hosts Visualizing Dashboards Customizing Performance Graph The NetEye Geo Map Visualizer Map Viewer Configuring Geo Maps NagVis 3b Audit Log 3b Overview Shutdown Manager user Shutdown Manager GUI Shutdown Commands Advanced Topics Overview User Role Management Cube Use Cases ntopng and NetEye Integration Permissions Retention Advanced Topics Overview User Roles Nodes Test Cases Dashboard Use Cases Overview Architecture Authorization Elasticsearch Overview Enabling El Proxy Sending custom logs to El Proxy Configuration files Commands Elasticsearch Templates and Retentions El Proxy DLQ Blockchain Verification Handling Blockchain Corruptions El Proxy Metrics El Proxy Security El Proxy REST Endpoints Agents Logstash Elastic APM Elastic RUM Log Manager - Deprecated Overview Authorization in the Command Orchestrator Module Configuring CLI Commands Executing Commands Overview Permissions Installation Single Tenancy Multitenancy Communication through a Satellite Asset collection methods Display asset information in monitoring host page Overview Customers Availability Event Adjustment Outages Resource Advanced Topics Introduction Getting Started SATAYO Items Settings Managed Service Mitre Attack Coverage Changelog Before you start Update Procedure Single Node Upgrade from 4.42 to 4.43 Cluster Upgrade from 4.42 to 4.43 Satellite Upgrade from 4.42 to 4.43 DPO machine Upgrade from 4.42 to 4.43 Create a mirror of the RPM repository Sprint Releases Feature Troubleshooting Tornado Networking Service Management - Incident Response IT Operation Analytics - Telemetry Identity Provider (IdP) Configuration Introduction to NEP Getting Started with NEPs Online Resources Obtaining NEP Insights Available Packages Advanced Topics Upgrade to NetEye 4.31 Setup Configure swappiness Restarting Stopped Services Enable stack traces in web UI How to access standard logs Director does not deploy when services assigned to a host have the same name How to enable/disable debug logging Activate Debug Logging for Tornado Modules/Services do not start Sync Rule fails when trying to recreate Icinga object How to disable InfluxDB query logging Managing an Elasticsearch Cluster with a Full Disk Some logs are not indexed in Elasticsearch Elasticsearch is not functioning properly Reporting: Error when opening a report Debugging Logstash file input filter Bugfix Policy Reporting Vulnerabilities Glossary 3b

El Proxy DLQ

Handling Logs in Dead Letter Queue

Logs which could not be indexed in Elasticsearch are written in the DLQ of El Proxy.

Since events written in the DLQ are not part of the secured blockchain indices, the NetEye Administrator needs to recover or explicitly acknowledge the presence of the events in the DLQ.

As soon as any log ends up in the DLQ, the Icinga2 service logmanager-blockchain-creation-neteyelocal will enter in CRITICAL state, indicating that some log could not be indexed in the blockchain.

To recover the logs, the NetEye admin can use the dlq recover command, which will try to write the DLQ logs on Elasticsearch in their original Data Stream (see How the data stream name is determined). If some of the logs cannot be recovered, they will remain in the DLQ.

Warning

To ensure that recovered logs are not kept in Elasticsearch longer than their retention period, please execute the dlq recover command as soon as logs end up in DLQ.

The retention of the logs starts from the moment when the logs are written in Elasticsearch, which means that if you for example recover logs from DLQ after one month, those logs will be kept in Elasticsearch one month more than the expected retention period.

If for any reason you cannot recover DLQ via the dlq recover command, a blockchain corruption will be reported by the next El Proxy verification because some logs are missing in the blockchain saved on Elasticsearch. You can then acknowledge the corruption ID reported by the verification by following the procedure in Handling Blockchain Corruptions.

To clean up the DLQ and solve the CRITICAL state of logmanager-blockchain-creation-neteyelocal please:

  1. Ensure the logs do not contain signs of malicious activities by inspecting the content of the DLQ log files /neteye/shared/elastic-blockchain-proxy/data/dlq/<tenant>/<filename>, where <tenant> is the name of the tenant that generated the log, and <filename> is the name of the log file.

  2. Delete the logs from the DLQ by deleting the log files in the directory /neteye/shared/elastic-blockchain-proxy/data/dlq/<tenant>.

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