Kubernetes Network: Debugging and Monitoring Tools

Kubernetes Network: Debugging and Monitoring Tools.md

Tool	Description
calicoctl	for managing Calico network policies and resources. We can use calicoctl to check the network policies that are applied to the pods and services in our cluster, and to add or delete policies if needed
curl	Transfers data from or to a server using various protocols, such as HTTP, HTTPS, FTP, etc. It can help us test if a service or pod is responding to requests correctly and measure the latency and throughput
dig	Performs DNS queries and displays detailed information about the responses
ip	Command-line tool for manipulating IP addresses and routes on Linux systems. We can use ip to check the IP addresses and routes of the pods and nodes in our cluster, and to add or delete routes if needed
iperf	Measures the bandwidth and quality of a network link by generating TCP or UDP traffic. It can help us benchmark the performance of the network between two nodes or pods
iptables	Command-line tool for managing firewall rules on Linux systems. We can use iptables to check the firewall rules that are applied to the pods and nodes in our cluster, and to add or delete rules if needed
kubectl	The command-line tool that allows us to interact with the Kubernetes API and resources. It has many subcommands and options that can help us inspect and manipulate the network objects, such as services, pods, endpoints, etc. For example, we can use kubectl describe to get detailed information about a service or pod, kubectl logs to view the logs of a pod or container, kubectl exec to run commands inside a pod or container, kubectl port-forward to forward a local port to a pod or service port
kubectl exec	executes commands inside a container in a pod
kubectl logs	prints the logs of a container in a pod
kubectl port-forward	forwards one or more local ports to a pod
kubectl proxy	creates a proxy server that provides access to the Kubernetes API server
kubectl top	displays CPU and memory usage of nodes and pods
netstat	Displays various network statistics, such as connections, routing tables, interface statistics, etc. It can help us monitor the network status and activity on a node or pod
nslookup	For querying DNS servers and resolving domain names to IP addresses. We can use nslookup to check the DNS records and resolution of the pods and services in our cluster, and to verify that they are correct and consistent
ping	A simple tool that tests the connectivity between two hosts by sending ICMP packets and measuring the response time. It can help us check if a pod or node is reachable from another pod or node
tcpdump	Captures and analyzes the network traffic on a given interface or filter. It can help us inspect the packets in detail and troubleshoot low-level network issues
traceroute	Traces the route of packets from one host to another and displays the hops along the way. It can help us identify where the packets are dropped or delayed in the network