Telepresence gives developers infinite scale development environments for Kubernetes.
With Telepresence:
- You run your services locally, using your favorite IDE and other tools
- Your workstation is connected to the cluster and can access to its services
This gives developers:
- A fast local dev loop, with no waiting for a container build / push / deploy
- Ability to use their favorite local tools (IDE, debugger, etc.)
- Ability to run large-scale applications that can't run locally
A few quick ways to start using Telepresence:
- Telepresence Quick Start: Quick Start
- Install Telepresence: Install
- Contributor's Guide: Guide
- Meetings: Check out our community meeting schedule for opportunities to interact with Telepresence developers
Find out more about Telepresence Enterprise and related products at getambassador.io.
Start with an empty cluster:
$ kubectl create deploy hello --image=registry.k8s.io/echoserver:1.4
deployment.apps/hello created
$ kubectl expose deploy hello --port 80 --target-port 8080
service/hello exposed
$ kubectl get ns,svc,deploy,po
NAME STATUS AGE
namespace/kube-system Active 53m
namespace/default Active 53m
namespace/kube-public Active 53m
namespace/kube-node-lease Active 53m
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/kubernetes ClusterIP 10.43.0.1 <none> 443/TCP 53m
service/hello ClusterIP 10.43.73.112 <none> 80/TCP 2m
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/hello 1/1 1 1 2m
NAME READY STATUS RESTARTS AGE
pod/hello-9954f98bf-6p2k9 1/1 Running 0 2m15sCheck telepresence version
$ telepresence version
OSS Client : v2.17.0
Root Daemon: not running
User Daemon: not runningInstall Traffic Manager in your cluster. By default, it will reside in the ambassador namespace:
$ telepresence helm install
Traffic Manager installed successfullyLet telepresence connect:
$ telepresence connect
Launching Telepresence Root Daemon
Launching Telepresence User Daemon
Connected to context default, namespace default (https://35.232.104.64)A session is now active and outbound connections will be routed to the cluster. I.e. your laptop is logically "inside" a namespace in the cluster.
Since telepresence connected to the default namespace, all services in that namespace can now be reached directly
by their name. You can of course also use namespaced names, e.g. curl hello.default.
$ curl hello
CLIENT VALUES:
client_address=10.244.0.87
command=GET
real path=/
query=nil
request_version=1.1
request_uri=http://hello:8080/
SERVER VALUES:
server_version=nginx: 1.10.0 - lua: 10001
HEADERS RECEIVED:
accept=*/*
host=hello
user-agent=curl/8.0.1
BODY:
-no body in request-Add an intercept for the hello deployment on port 9000. Here, we also start a service listening on that port:
$ telepresence intercept hello --port 9000 -- python3 -m http.server 9000
Using Deployment hello
intercepted
Intercept name : hello
State : ACTIVE
Workload kind : Deployment
Destination : 127.0.0.1:9000
Service Port Identifier: 80
Volume Mount Point : /tmp/telfs-524630891
Intercepting : all TCP connections
Serving HTTP on 0.0.0.0 port 9000 (http://0.0.0.0:9000/) ...The python -m httpserver is now started on port 9000 and will run until terminated by <ctrl>-C. Access it from a browser using http://hello/ or use curl from another terminal. With curl, it presents a html listing from the directory where the server was started. Something like:
$ curl hello
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Directory listing for /</title>
</head>
<body>
<h1>Directory listing for /</h1>
<hr>
<ul>
<li><a href="file1.txt">file1.txt</a></li>
<li><a href="file2.txt">file2.txt</a></li>
</ul>
<hr>
</body>
</html>Observe that the python service reports that it's being accessed:
127.0.0.1 - - [16/Jun/2022 11:39:20] "GET / HTTP/1.1" 200 -
End the service with <ctrl>-C and then try curl hello or http://hello again. The intercept is gone, and the echo service responds as normal.
Now end the session too. Your desktop no longer has access to the cluster internals.
$ telepresence quit
Disconnected
$ curl hello
curl: (6) Could not resolve host: helloThe telepresence daemons are still running in the background, which is harmless. You'll need to stop them before you
upgrade telepresence. That's done by passing the option -s (stop all local telepresence daemons) to the
quit command.
$ telepresence quit -s
Telepresence Daemons quitting...doneTelepresence installs the Traffic Manager in your cluster if it is not already present. This deployment remains unless you uninstall it.
Telepresence injects the Traffic Agent as an additional container into the pods of the workload you intercept, and will optionally install
an init-container to route traffic through the agent (the init-container is only injected when the service is headless or uses a numerical
targetPort). The modifications persist unless you uninstall them.
At first glance, we can see that the deployment is installed ...
$ kubectl get svc,deploy,pod
service/kubernetes ClusterIP 10.43.0.1 <none> 443/TCP 7d22h
service/hello ClusterIP 10.43.145.57 <none> 80/TCP 13m
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/hello 1/1 1 1 13m
NAME READY STATUS RESTARTS AGE
pod/hello-774455b6f5-6x6vs 2/2 Running 0 10m... and that the traffic-manager is installed in the "ambassador" namespace.
$ kubectl -n ambassador get svc,deploy,pod
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/traffic-manager ClusterIP None <none> 8081/TCP 17m
service/agent-injector ClusterIP 10.43.72.154 <none> 443/TCP 17m
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/traffic-manager 1/1 1 1 17m
NAME READY STATUS RESTARTS AGE
pod/traffic-manager-dcd4cc64f-6v5bp 1/1 Running 0 17mThe traffic-agent is installed too, in the hello pod. Here together with an init-container, because the service is using a numerical
targetPort.
$ kubectl describe pod hello-774455b6f5-6x6vs
Name: hello-75b7c6d484-9r4xd
Namespace: default
Priority: 0
Service Account: default
Node: kind-control-plane/192.168.96.2
Start Time: Sun, 07 Jan 2024 01:01:33 +0100
Labels: app=hello
pod-template-hash=75b7c6d484
telepresence.io/workloadEnabled=true
telepresence.io/workloadName=hello
Annotations: telepresence.getambassador.io/inject-traffic-agent: enabled
telepresence.getambassador.io/restartedAt: 2024-01-07T00:01:33Z
Status: Running
IP: 10.244.0.89
IPs:
IP: 10.244.0.89
Controlled By: ReplicaSet/hello-75b7c6d484
Init Containers:
tel-agent-init:
Container ID: containerd://4acdf45992980e2796f0eb79fb41afb1a57808d108eb14a355cb390ccc764571
Image: docker.io/datawire/tel2:2.17.0
Image ID: docker.io/datawire/tel2@sha256:e18aed6e7bd3c15cb5a99161c164e0303d20156af68ef138faca98dc2c5754a7
Port: <none>
Host Port: <none>
Args:
agent-init
State: Terminated
Reason: Completed
Exit Code: 0
Started: Sun, 07 Jan 2024 01:01:34 +0100
Finished: Sun, 07 Jan 2024 01:01:34 +0100
Ready: True
Restart Count: 0
Environment: <none>
Mounts:
/etc/traffic-agent from traffic-config (rw)
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-svf4h (ro)
Containers:
echoserver:
Container ID: containerd://577e140545f3106c90078e687e0db3661db815062084bb0c9f6b2d0b4f949308
Image: registry.k8s.io/echoserver:1.4
Image ID: sha256:523cad1a4df732d41406c9de49f932cd60d56ffd50619158a2977fd1066028f9
Port: <none>
Host Port: <none>
State: Running
Started: Sun, 07 Jan 2024 01:01:34 +0100
Ready: True
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-svf4h (ro)
traffic-agent:
Container ID: containerd://17558b4711903f4cb580c5afafa169d314a7deaf33faa749f59d3a2f8eed80a9
Image: docker.io/datawire/tel2:2.17.0
Image ID: docker.io/datawire/tel2@sha256:e18aed6e7bd3c15cb5a99161c164e0303d20156af68ef138faca98dc2c5754a7
Port: 9900/TCP
Host Port: 0/TCP
Args:
agent
State: Running
Started: Sun, 07 Jan 2024 01:01:34 +0100
Ready: True
Restart Count: 0
Readiness: exec [/bin/stat /tmp/agent/ready] delay=0s timeout=1s period=10s #success=1 #failure=3
Environment:
_TEL_AGENT_POD_IP: (v1:status.podIP)
_TEL_AGENT_NAME: hello-75b7c6d484-9r4xd (v1:metadata.name)
A_TELEPRESENCE_MOUNTS: /var/run/secrets/kubernetes.io/serviceaccount
Mounts:
/etc/traffic-agent from traffic-config (rw)
/tel_app_exports from export-volume (rw)
/tel_app_mounts/echoserver/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-svf4h (ro)
/tel_pod_info from traffic-annotations (rw)
/tmp from tel-agent-tmp (rw)
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-svf4h (ro)
Conditions:
Type Status
Initialized True
Ready True
ContainersReady True
PodScheduled True
Volumes:
kube-api-access-svf4h:
Type: Projected (a volume that contains injected data from multiple sources)
TokenExpirationSeconds: 3607
ConfigMapName: kube-root-ca.crt
ConfigMapOptional: <nil>
DownwardAPI: true
traffic-annotations:
Type: DownwardAPI (a volume populated by information about the pod)
Items:
metadata.annotations -> annotations
traffic-config:
Type: ConfigMap (a volume populated by a ConfigMap)
Name: telepresence-agents
Optional: false
export-volume:
Type: EmptyDir (a temporary directory that shares a pod's lifetime)
Medium:
SizeLimit: <unset>
tel-agent-tmp:
Type: EmptyDir (a temporary directory that shares a pod's lifetime)
Medium:
SizeLimit: <unset>
QoS Class: BestEffort
Node-Selectors: <none>
Tolerations: node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal Scheduled 7m40s default-scheduler Successfully assigned default/hello-75b7c6d484-9r4xd to kind-control-plane
Normal Pulled 7m40s kubelet Container image "docker.io/datawire/tel2:2.17.0" already present on machine
Normal Created 7m40s kubelet Created container tel-agent-init
Normal Started 7m39s kubelet Started container tel-agent-init
Normal Pulled 7m39s kubelet Container image "registry.k8s.io/echoserver:1.4" already present on machine
Normal Created 7m39s kubelet Created container echoserver
Normal Started 7m39s kubelet Started container echoserver
Normal Pulled 7m39s kubelet Container image "docker.io/datawire/tel2:2.17.0" already present on machine
Normal Created 7m39s kubelet Created container traffic-agent
Normal Started 7m39s kubelet Started container traffic-agentTelepresence keeps track of all possible intercepts for containers that have an agent installed in the configmap telepresence-agents.
$ kubectl describe configmap telepresence-agents
Name: telepresence-agents
Namespace: default
Labels: app.kubernetes.io/created-by=traffic-manager
app.kubernetes.io/name=telepresence-agents
app.kubernetes.io/version=2.17.0
Annotations: <none>
Data
====
hello:
----
agentImage: localhost:5000/tel2:2.17.0
agentName: hello
containers:
- Mounts: null
envPrefix: A_
intercepts:
- agentPort: 9900
containerPort: 8080
protocol: TCP
serviceName: hello
servicePort: 80
serviceUID: 68a4ecd7-0a12-44e2-9293-dc16fb205621
targetPortNumeric: true
mountPoint: /tel_app_mounts/echoserver
name: echoserver
logLevel: debug
managerHost: traffic-manager.ambassador
managerPort: 8081
namespace: default
pullPolicy: IfNotPresent
tracingPort: 15766
workloadKind: Deployment
workloadName: hello
BinaryData
====
Events: <none>You can uninstall the traffic-agent from specific deployments or from all deployments. Or you can choose to uninstall everything in which case the traffic-manager and all traffic-agents will be uninstalled.
$ telepresence helm uninstallwill remove everything that was automatically installed by telepresence from the cluster.
$ telepresence uninstall --agent hellowill remove the traffic-agent and the configmap entry.
The telepresence background processes daemon and connector both produces log files that can be very helpful when problems are
encountered. The files are named daemon.log and connector.log. The location of the logs differ depending on what platform that is used:
- macOS
~/Library/Logs/telepresence - Linux
~/.cache/telepresence/logs - Windows
"%USERPROFILE%\AppData\Local\logs"
When Telepresence 2 connects to a Kubernetes cluster, it
- Ensures Traffic Manager is installed in the cluster.
- Looks for the relevant subnets in the kubernetes cluster.
- Creates a Virtual Network Interface (VIF).
- Assigns the cluster's subnets to the VIF.
- Binds itself to VIF and starts routing traffic to the traffic-manager, or a traffic-agent if one is present.
- Starts listening for, and serving DNS requests, by passing a selected portion to the traffic-manager or traffic-agent.
When a locally running application makes a network request to a service in the cluster, Telepresence will resolve the name to an address within the cluster.
The operating system then sees that the TUN device has an address in the same subnet as the address of the outgoing packets and sends them to tel0.
Telepresence is on the other side of tel0 and picks up the packets, injecting them into the cluster through a gRPC connection with Traffic Manager.
For a more in-depth overview, checkout our blog post: Implementing Telepresence Networking with a TUN device
Visit the troubleshooting section in the Telepresence documentation for more advice: Troubleshooting
Or discuss with the community in the CNCF Slack in the #telepresence-oss channel.
