Vector is an open-source utility for collecting, transforming, and routing log and metrics data.
kube-iptables-tailer is a service that gives you better visibility on networking issues in your Kubernetes cluster by detecting the traffic denied by iptables and surfacing corresponding information to the affected Pods via Kubernetes events.
OK Log is a distributed and coördination-free log management system for big ol' clusters. It's an on-prem solution that's designed to be a sort of building block: easy to understand, easy to operate, and easy to extend.
Cernan is a telemetry and logging aggregation server. It exposes multiple interfaces for ingestion and can emit to multiple aggregation sources while doing in-flight manipulation of data. Cernan has minimal CPU and memory requirements and is intended to service bursty telemetry without load shedding. Cernan aims to be reliable and convenient to use, both for application engineers and operations staff.
Collect and forward system metrics using portable shell scripts
extract whitebox monitoring data from application logs for collection in a timeseries database
Log every executed command to syslog (a.k.a. Snoopy Logger).
Kibana plugin to view, search & live tail log events
This little tool helps you with figuring out a good initial hardware sizing for Graylog setups. Keep in mind that the required hardware heavily depends on how you use Graylog and what the log messages look like. Use the recommendations generated by this tool as a starting point and then fine-tune the sizing as required. Especially everything related to storage can differ a lot from setup to setup.