Centralized logging is no longer optional. Whether you’re troubleshooting production incidents, investigating suspicious activity, or meeting audit requirements, you need a way to collect logs from many sources, normalize them, search them quickly, and turn them into alerts and dashboards. In practice, that starts with reliable collection — often via solutions like NXLog Platform — so the data arrives clean and consistent.
Two of the most common open-source paths people compare are Graylog vs ELK Stack. Both can solve real log management problems, but they do it with different architectures, different operational tradeoffs, and different "hidden costs" (time, infrastructure, and ongoing maintenance).
This guide compares Graylog and the ELK/Elastic Stack from an engineering and decision-making standpoint: setup complexity, scalability, performance, UI/dashboards, alerting, integrations, and which tool fits which use case. We’ll also briefly cover the ingestion layer, because in practice, the "best" platform is the one you can feed reliably with clean, consistent data. That ingestion layer is typically where tools like NXLog Platform or Beats enter the solution design.
Overview of Graylog and ELK
What is Graylog?
Graylog is a log management and analytics platform that centralizes machine data so teams can search, visualize, and alert on it. Graylog positions itself as a SIEM-capable platform and log analytics tool used for cybersecurity, IT operations, and compliance workflows.
Graylog uses a centralized architecture where lightweight collectors or standard logging protocols ship data into a Graylog server backed by OpenSearch for search and analysis and MongoDB for metadata and configuration.
Graylog comes in multiple editions, including Graylog Open, Graylog Operations, Graylog Security, and Graylog Cloud (managed).
What is the ELK Stack?
ELK Stack traditionally refers to these components:
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Elasticsearch (indexing + search engine)
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Logstash (ingest/processing pipelines)
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Kibana (visualization UI)
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Beats (data shipper for Elasticsearch)
You’ll also see it described as the Elastic Stack.
Elastic’s licensing has changed over time. In 2021, Elastic moved Elasticsearch and Kibana source code from Apache 2.0 to a dual-license model (SSPL + Elastic License). In 2024, Elastic announced adding AGPLv3 as an additional licensing option for Elasticsearch and Kibana source code. For most teams, the practical question isn’t just "is there an open-source license option?" but also which distribution/features you plan to use and what’s included in free versus paid tiers.
Common ground
At a high level, Graylog and ELK share a goal: centralize logs, index them for search, and support dashboards and alerts.
Where they diverge is in how much you assemble yourself (ELK) versus how much is packaged into a single experience (Graylog), and in how much the toolset extends beyond logs into broader observability.
Quick comparison table: Graylog vs ELK Stack
| Category | Graylog | ELK / Elastic Stack |
|---|---|---|
Core focus |
Log management + SIEM-style workflows |
Broader platform: logs + analytics + ecosystem |
Architecture style |
More integrated (Graylog server + OpenSearch + MongoDB) |
Modular (Elasticsearch + Logstash + Kibana + optional Beats) |
Architecture style |
More integrated (Graylog server + OpenSearch + MongoDB) |
Modular (Elasticsearch + Logstash + Kibana + optional Beats) |
Setup complexity |
Usually, fewer moving parts to get usable results |
More moving parts; flexible but more configuration |
Ingestion |
Network inputs; needs collectors for file-based logs |
Beats and/or Logstash pipelines are common |
Dashboards/UI |
Graylog UI is oriented around streams, searches, dashboards |
Kibana has very deep visualization capabilities |
Alerting |
Graylog supports alerts with event definitions; some alert types require Enterprise |
Elastic has alerting and Watcher features; capabilities vary by deployment/tier |
Best fit |
Teams prioritizing fast adoption for logs + alerting + investigation |
Teams needing customization, large ecosystems, or multi-signal observability |
Architecture and deployment
Graylog’s architecture in practice
Graylog often feels like a single product experience: you run the Graylog application and connect it to its dependencies. The major "gotcha" to understand today is the backend choice:
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Graylog documentation describes moving from Elasticsearch to OpenSearch and details OpenSearch support.
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Graylog’s compatibility matrix shows supported OpenSearch ranges per Graylog version (for example, Graylog 6.x supports OpenSearch 2.x within specific version ranges).
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OpenSearch 3.x support has been requested by users and tracked publicly, which matters if your organization wants features that only arrive in newer OpenSearch major versions.
Deployment options: self-managed Graylog (Open/Operations/Security) or Graylog Cloud.
ELK’s architecture in practice
The ELK/Elastic Stack is intentionally modular. That can be a strength if you need to scale and tune each part independently (more Logstash workers, more Elasticsearch data nodes, separate Kibana instances), but it also increases the number of places you need to configure and where failure can happen.
You can run it fully self-managed, or use hosted offerings (Elastic Cloud) while still managing shipper agents and pipelines.
Setup complexity: Graylog vs ELK Stack setup
The underlying question is usually: "Which one can my team operate without becoming a full-time job?"
A practical way to frame setup:
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Graylog: You set up Graylog + dependencies, create an input, and start receiving logs. Many configuration tasks (inputs, streams, dashboards, event definitions) happen in the Graylog UI.
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ELK: You typically configure multiple moving parts: Elasticsearch cluster settings, Logstash pipelines (or ingest pipelines), Kibana data views/dashboards, plus shipper agents (Beats) on endpoints.
One important nuance for Graylog ingestion: Graylog does not automatically read log files off disk by itself. Graylog’s docs describe ingesting from files by using log collection capabilities of NXLog Platform to forward logs into Graylog.
Graylog also offers Sidecar, which is essentially a centralized way to manage products with log collection features (including NXLog Platform and Beats) across endpoints.
Regardless of backend, teams usually standardize the edge layer first — e.g., NXLog Platform for endpoint collection and routing — then plug into Graylog or Elastic.
Scalability and performance
Horizontal scaling: Graylog vs ELK scalability
Both platforms can scale horizontally, but the scaling "shape" differs.
- Graylog scaling
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Graylog supports clustering (multiple Graylog nodes) backed by an OpenSearch cluster.
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The practical limits and tuning concerns are often tied to OpenSearch sizing, indexing strategy, and the specific supported OpenSearch versions for your Graylog release.
If your organization is sensitive to "version lock," treat the Graylog compatibility matrix as part of your platform decision, not as an afterthought.
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- ELK / Elastic Stack scaling
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Elasticsearch is designed to scale by adding nodes/shards and tuning ingestion/query patterns.
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You can run multiple Logstash instances for throughput and isolate pipelines for different data types.
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Kibana can scale for more users and dashboards.
This flexibility is why ELK is common in very large environments and in cases where teams want to expand beyond logs into other analytics use cases.
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Graylog vs ELK performance: what benchmark data suggests
Most blog comparisons stay qualitative. There is at least one academic paper that provides a clear set of "out-of-the-box" test results:
A 2022 performance evaluation compared ELK Stack and Graylog under two throughputs (roughly 100GB/day and 1TB/day[1]) and measured CPU/memory usage and response time.
Key findings from that study (useful as directional data, not a promise):
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At ~100GB/day, CPU usage was similar (both averaging roughly 50–60% in their test environment).
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Memory usage: the study reported ELK was ~1.6x more memory-consuming than Graylog under the tested conditions.
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Response time: ELK was reported ~1.5x faster in their API query response test (about 73ms vs 110ms).
How to interpret this for real deployments:
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If infrastructure cost and footprint are a concern, Graylog may be easier to run at moderate volumes.
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If you need maximum query flexibility and have the resources (and staffing) to tune Elasticsearch/Logstash properly, ELK can perform very well — especially at scale.
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Your results will vary based on versions, pipelines, mapping choices, indexing strategy, and hardware.
Features and capabilities
Search and dashboard UI: Graylog vs Kibana
Comparing Graylog vs Kibana means you’re really comparing user experience and visualization power.
- Graylog UI
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Many teams find Graylog’s UI straightforward for day-to-day log search, stream separation, and operational workflows.
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Graylog emphasizes streams, pipelines, and a guided UI experience.
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- Kibana
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Kibana is exceptionally flexible for visual analytics and dashboards, especially when combined with Elastic’s query language and aggregations.
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The tradeoff is that teams often need more expertise to use Kibana to its full potential and maintain consistent dashboards at scale.
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Alerting: Graylog vs ELK alerting
Alerting is often the deciding factor for SOC and operations teams.
- Graylog alerting
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Graylog supports alerts through event definitions, triggers, and notifications, with certain notification types requiring Enterprise (for example, script and PagerDuty alerts). For many teams, the key point is that Graylog’s alerting workflow is integrated into the product UX: define conditions, attach notifications, and manage alerts/events inside Graylog.
- ELK alerting
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Elastic’s feature set depends heavily on the deployment model and tier. Elastic provides alerting and rules capabilities within Kibana, and documents Watcher as an alerting mechanism for more complex use cases. In practice, teams should evaluate:
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Do you need simple threshold alerts, or complex correlation/anomaly logic?
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Do you want alerting inside the same UI as search/dashboards?
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What’s included in the tier you plan to use?
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Extensibility and integrations (and where NXLog Platform fits)
- Graylog ecosystem
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Graylog supports common log ingestion patterns via inputs (syslog, GELF, Beats, cloud/service inputs) and supports collector management through Sidecar.
- ELK ecosystem
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ELK has a large ecosystem: Beats agents, Logstash plugins, Kibana integrations, and many community patterns.
The ingestion layer is where many debates become practical. Most teams don’t choose Graylog or ELK in isolation — they also choose how logs get collected from:
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Linux servers (files, syslog)
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Windows Event Logs
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Ntwork devices
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Containers and orchestrators
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SaaS/cloud sources
Graylog documentation explicitly describes ingesting from files by using solutions with log collection capabilities like NXLog Platform, and forwarding via protocols such as GELF or syslog.
Graylog Sidecar can manage these solutions including NXLog Platform, centralizing configuration through the Graylog UI.
From an NXLog Platform perspective: NXLog Platform can act as the collection + preprocessing layer — parsing, filtering noise, adding fields, and routing logs — before forwarding to either Graylog inputs or an Elastic pipeline. NXLog Platform’s Graylog integration documentation is a practical reference for what that looks like in real life (inputs, protocols, forwarding patterns).
Typical use cases: where each platform excels
When to choose Graylog
Graylog tends to be a good fit when you want:
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Faster time-to-value for centralized log management without assembling many separate components.
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A product experience oriented around streams, investigations, and alerting workflows (often appealing to IT operations and security teams).
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A clearer path to "SIEM-light" workflows, especially if you’re evaluating Graylog Security later.
Common environments:
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Mid-sized organizations centralizing logs for incident response and compliance
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Teams that want a simpler operational model for logs (and don’t need one stack for every data type)
When to choose ELK / Elastic Stack
ELK/Elastic Stack tends to be a good fit when you want:
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Maximum flexibility for ingest/transform/routing (Logstash pipelines and/or ingest pipelines).
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A platform that can expand into broader analytics and observability use cases (depending on your stack and tier).
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A large ecosystem of integrations and community patterns.
Common environments:
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Elastic-first organizations (already running Elasticsearch for other reasons)
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High-volume environments that invest in Elasticsearch tuning and cluster operations
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Teams that want deep Kibana dashboards and complex analytics workflows
Cost and resource considerations
Both platforms have free entry points, but your real cost is often:
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Infrastructure (RAM/CPU/storage)
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People time (maintenance, tuning, pipeline sprawl)
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Licensing if you rely on advanced features
Also keep licensing realities in view. Elastic has changed licensing over time and now offers AGPL as an option for Elasticsearch and Kibana source code. Separately, Graylog’s backend compatibility is tightly defined by its OpenSearch version support matrix.
Conclusion: which is better, Graylog or ELK?
Trying to compare Graylog vs ELK Stack depends on what you’re optimizing for, not on specific isolated features of either product. It depends on what you’re optimizing for.
Choose Graylog when:
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You want a log-focused platform that’s easier to adopt and operate
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You value integrated workflows (streams, events, alerts, investigations)
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You prefer a smaller set of moving parts
Choose ELK / Elastic Stack when:
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You need maximum flexibility and customization
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You expect to grow into a wide range of analytics/observability use cases
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You have the appetite (and staff) to run and tune a modular stack
Regardless of which platform you pick, treat log collection and normalization as a first-class decision. Graylog’s own docs recommend solutions like NXLog Platform for ingesting logs from files, and Sidecar can centrally manage NXLog Platform at scale.
FAQ: Graylog vs ELK Stack
Q: Is Graylog an alternative to ELK?
A: Yes. Graylog is commonly used as an ELK Stack alternative for teams that want centralized log management with a simpler operational footprint, while still supporting search, dashboards, and alerts.
Q: Does Graylog use Elasticsearch?
A: Modern Graylog versions are centered around OpenSearch compatibility, and Graylog publishes a compatibility matrix specifying supported OpenSearch versions for each Graylog release.
Q: Can ELK do alerting without paid features?
A: Elastic provides alerting and rules in Kibana, and also documents Watcher for certain alerting workflows, but what you can use depends on your deployment/tier and chosen feature set.
Q: Do I need an agent to send logs to Graylog?
A: Often, yes. Graylog documentation describes ingesting from files using solutions like NXLog Platform that forward logs into Graylog inputs.