How many types of probes are there in Kubernetes?

Three types of probes in Kubernetes:

1. livenessProbe: Determines when a container is unhealthy. If the probe fails, kubelet kills the container and manages its restart according to the restart policy.
2. readinessProbe: Determines if the container is ready to handle requests. If the probe fails, kubelet stops sending traffic to this pod until the probe succeeds.
3. startupProbe: Determines if the container has completed initialization. If specified, other probes (liveness and readiness) are disabled until this probe succeeds. This is useful for slow-starting containers, preventing their termination or disconnection from the service until they are ready.

Each probe type can be implemented using three mechanisms:

• exec: Executes a specified command inside the container. The probe is successful if the command exits with a code 0.
• httpGet: Performs an HTTP GET request to the specified IP address, port, and path. The probe is successful if the response code is between 200 and 399.
• tcpSocket: Performs a TCP check on the specified port of the container. The probe is successful if the port is open.