Telepresence 2: fast, efficient local development for Kubernetes microservices
Telepresence gives developers infinite scale development environments for Kubernetes.
Website: https://www.getambassador.io/products/telepresence/
Slack: Discuss in the #telepresence channel (https://datawire-oss.slack.com/archives/CAUBBJSQZ)
With Telepresence:
- You run one service locally, using your favorite IDE and other tools
- You run the rest of your application in the cloud, where there is unlimited memory and compute
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
Quick Start
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
Documentation
Telepresence documentation is available on the Ambassador Labs webside:
Documentation
Telepresence 2
Telepresence 2 is based on learnings from the original Telepresence architecture. Rewritten in Go, Telepresence 2 provides a simpler and more powerful user experience, improved performance, and better reliability than Telepresence 1. More details on Telepresence 2 are below.
Walkthrough
Install an interceptable service:
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 2m15s
Check telepresence version
$ telepresence version
Client: v2.6.7 (api v3)
Root Daemon: v2.6.7 (api v3)
User Daemon: v2.6.7 (api v3)
Setup Traffic Manager in the cluster
Install Traffic Manager in your cluster. By default, it will reside in the ambassador
namespace:
$ telepresence helm install
Traffic Manager installed successfully
Establish a connection to the cluster (outbound traffic)
Let telepresence connect:
$ telepresence connect
Launching Telepresence Root Daemon
Launching Telepresence User Daemon
Connected to context 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 "inside" the cluster.
$ curl hello.default
CLIENT VALUES:
client_address=10.42.0.189
command=GET
real path=/
query=nil
request_version=1.1
request_uri=http://hello.default:8080/
SERVER VALUES:
server_version=nginx: 1.10.0 - lua: 10001
HEADERS RECEIVED:
accept=*/*
host=hello.default
user-agent=curl/7.79.1
BODY:
-no body in request-
Intercept the service. I.e. redirect traffic to it to our laptop (inbound traffic)
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 requests
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 -
Since telepresence is now intercepting services in the default namespace, all services in that namespace can now be reached directly by their name. You can of course still use the namespaced name too, e.g. curl hello.default
.
Clean-up and close daemon processes
End the service with <ctrl>-C
and then try curl hello.default
or http://hello.default
again. The intercept is gone, and the echo service responds as normal. Using just curl hello
will no longer succeed. This is because telepresence stopped mapping the default namespace when there were no more intercepts using it.
Now end the session too. Your desktop no longer has access to the cluster internals.
$ telepresence quit
Telepresence Network disconnecting...done
Telepresence Traffic Manager disconnecting...done
$ curl hello.default
curl: (6) Could not resolve host: hello.default
The 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 options -u
(stop user daemon) and -r
(stop root daemon) to the
quit command.
$ telepresence quit -ur
Telepresence Network quitting...done
Telepresence Traffic Manager quitting...done
What got installed in the cluster?
Telepresence 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 17m
The 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-774455b6f5-6x6vs
Namespace: default
Priority: 0
Node: multi/192.168.1.110
Start Time: Thu, 16 Jun 2022 11:38:22 +0200
Labels: app=hello
pod-template-hash=774455b6f5
Annotations: telepresence.getambassador.io/inject-traffic-agent: enabled
telepresence.getambassador.io/restartedAt: 2022-06-16T09:38:21Z
Status: Running
IP: 10.42.0.191
IPs:
IP: 10.42.0.191
Controlled By: ReplicaSet/hello-774455b6f5
Init Containers:
tel-agent-init:
Container ID: containerd://e968352b3d85d6f966ac55f02da2401f93935f6df1f087b06bbe1cfc8854d5fb
Image: docker.io/datawire/ambassador-telepresence-agent:1.12.6
Image ID: docker.io/datawire/ambassador-telepresence-agent@sha256:2652d2767d1e8968be3fb22f365747315e25ac95e12c3d39f1206080a1e66af3
Port: <none>
Host Port: <none>
Args:
agent-init
State: Terminated
Reason: Completed
Exit Code: 0
Started: Thu, 16 Jun 2022 11:38:39 +0200
Finished: Thu, 16 Jun 2022 11:38:39 +0200
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-wzhhs (ro)
Containers:
echoserver:
Container ID: containerd://80d4645769a06b8671b5a4ce29d28abfa72ce5659ba96916c231bb9629593a29
Image: registry.k8s.io/echoserver:1.4
Image ID: sha256:523cad1a4df732d41406c9de49f932cd60d56ffd50619158a2977fd1066028f9
Port: <none>
Host Port: <none>
State: Running
Started: Thu, 16 Jun 2022 11:38:40 +0200
Ready: True
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-wzhhs (ro)
traffic-agent:
Container ID: containerd://ef3605a60f7c02229f156e3dc0e99f9b055fba1037587513871e64180670d0a4
Image: docker.io/datawire/ambassador-telepresence-agent:1.12.6
Image ID: docker.io/datawire/ambassador-telepresence-agent@sha256:2652d2767d1e8968be3fb22f365747315e25ac95e12c3d39f1206080a1e66af3
Port: 9900/TCP
Host Port: 0/TCP
Args:
agent
State: Running
Started: Thu, 16 Jun 2022 11:38:41 +0200
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-774455b6f5-6x6vs (v1:metadata.name)
Mounts:
/etc/traffic-agent from traffic-config (rw)
/tel_app_exports from export-volume (rw)
/tel_pod_info from traffic-annotations (rw)
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-wzhhs (ro)
Conditions:
Type Status
Initialized True
Ready True
ContainersReady True
PodScheduled True
Volumes:
kube-api-access-wzhhs:
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>
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 13m default-scheduler Successfully assigned default/hello-774455b6f5-6x6vs to multi
Normal Pulling 13m kubelet Pulling image "docker.io/datawire/ambassador-telepresence-agent:1.12.6"
Normal Pulled 13m kubelet Successfully pulled image "docker.io/datawire/ambassador-telepresence-agent:1.12.6" in 17.043659509s
Normal Created 13m kubelet Created container tel-agent-init
Normal Started 13m kubelet Started container tel-agent-init
Normal Pulled 13m kubelet Container image "registry.k8s.io/echoserver:1.4" already present on machine
Normal Created 13m kubelet Created container echoserver
Normal Started 13m kubelet Started container echoserver
Normal Pulled 13m kubelet Container image "docker.io/datawire/ambassador-telepresence-agent:1.12.6" already present on machine
Normal Created 13m kubelet Created container traffic-agent
Normal Started 13m kubelet Started container traffic-agent
Uninstalling
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 uninstall
will remove everything that was automatically installed by telepresence from the cluster.
Troubleshooting
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"
Visit the troubleshooting section in the Telepresence documentation for more advice:
Troubleshooting