Cilium Features
You set up cilium features by running its agent on each cluster node. This agent loads eBPF programs into the Linux kernel to manage traffic. Teams often start by replacing old packet filter rules in their clusters. They map container labels to network rules so apps can talk. Still, broad network rules often let too much traffic pass between services. Once a role or pod gets network clearance, it can send bad requests. How cilium features work inside the Linux kernel Cilium runs a background
Linkerd Security Features + Cilium Network Policies: the complete guide
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You set up cilium features by running its agent on each cluster node. This agent loads eBPF programs into the Linux kernel to manage traffic. Teams often start by replacing old packet filter rules in their clusters. They map container labels to network rules so apps can talk. Still, broad network rules often let too much traffic pass between services. Once a role or pod gets network clearance, it can send bad requests.
How cilium features work inside the Linux kernel
Cilium runs a background agent on every host in your container cluster. This agent reads your container labels and service rules from the cluster API. Then it compiles small eBPF programs and loads them into the kernel. The Linux kernel runs these programs whenever a packet moves through a socket.
Old network tools check IP addresses and ports at every hop. Containers start and stop fast, so IP addresses change all the time. Cilium gives each group of containers a security ID based on labels. The kernel checks this ID before sending data from one pod to another. This shift speeds up packet routing and stops IP churn issues.
Beyond basic packet routing, the tool also replaces standard cluster load balancers. It intercepts service traffic right at the socket level on the host. Data moves straight to the backend pod without extra network hops. It can also encrypt traffic between nodes using standard Linux kernel encryption. Teams use its flow logs to see which pods talk to each other.
What native network rules solve and what they miss
Kernel networking solves pod-to-pod routing and blocks unapproved network paths fast. It stops a frontend web app from reaching an internal billing service. It also gives platform teams clear maps of service calls across nodes. You can filter basic web paths and methods between your internal apps.
Still, container network rules only govern how pods talk to other pods. They do not manage how humans or scripts run commands inside databases. A network rule decides if a pod can reach a database port. It does not check the specific database query running inside that session. If an engineer logs into a cluster pod, the network allows their traffic.
Linkerd Security Features + Cilium Network Policies: architecture patterns and best practices
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Network rules also cannot redact private data inside database query results. If a query returns emails, phone numbers, or card numbers, the network passes them. To protect live data, teams must inspect individual queries and commands in flight. You need controls that check user identity and mask fields before returning results.
Steps to plan your cluster network rules
Start by running the network agent in monitor mode on test nodes. Watch the flow logs to see which apps talk to each other today. Group your apps by role labels rather than by static IP ranges. Write simple rules that only allow required paths between those specific app groups.
Test your rules during peak load to check that all services respond. Turn on node encryption if your pods send sensitive data across cloud zones. Finally, pair your container network rules with direct controls for human database sessions. This keeps both your east-west pod traffic and your admin tasks safe.
Check database and API queries on the wire
Identity tools, roles, and network rules decide who opens a session. Setup alone cannot check what each query does or mask sensitive values in a response once a session starts. When workflows touch Postgres, MySQL, SQL Server, MongoDB, ClickHouse, Kubernetes APIs, SSH, or internal HTTP APIs, hoop.dev runs beside those services as an open-source proxy, a sidecar for your Postgres or API. It inspects requests coming in and results going back on the wire.
Your login details and client tools stay as they are while hoop.dev guardrails refuse bad deletes or drops before they run. On responses, hoop.dev data masking rewrites matched sensitive values in memory. Furthermore, hoop.dev holds SOC 2 Type II, is MIT licensed, and writes every query and decision to an audit trail that generates evidence for HIPAA, GDPR, and PCI DSS. See the source on GitHub.
Frequently asked questions
How does Cilium differ from standard Kubernetes network plugins?
Standard plugins write thousands of IP rules that slow down large clusters. Cilium uses kernel eBPF programs and pod labels to route packets fast.
Can Cilium inspect database queries from engineers?
No, it focuses on container network flows and basic service protocols. It does not inspect individual SQL queries or mask fields like national IDs.
Do I need a special Linux kernel to run Cilium?
You need a modern Linux kernel that supports standard eBPF hooks. Most current cloud node images include the required kernel support out of the box.