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'keys' does not handle special keys (like ^J) anymore. Instead, we should use `key`, which will pass its entire argument to tmux, without any processing. It is therefore possible to do something like: ```key ^C``` Or ```key Escape``` Most (if not all) calls to special keys have been converted to use 'key' instead of 'keys'. Action ```copypaste``` has been deprecated in favor of three separate actions: ```copy REGEX``` (searches the regex in the active pane, and if found, places it in an internal clipboard) ```paste``` (inserts the content of the clipboard as keystrokes) ```check``` (forces a status check) Also, a 'tmux' command has been added. It allows to do stuff like: ```tmux split-pane -v```
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Accessing internal services
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When we are logged in on a cluster node, we can access internal services
(by virtue of the Kubernetes network model: all nodes can reach all pods and services)
-
When we are accessing a remote cluster, things are different
(generally, our local machine won't have access to the cluster's internal subnet)
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How can we temporarily access a service without exposing it to everyone?
--
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kubectl proxy: gives us access to the API, which includes a proxy for HTTP resources -
kubectl port-forward: allows forwarding of TCP ports to arbitrary pods, services, ...
Suspension of disbelief
The exercises in this section assume that we have set up kubectl on our
local machine in order to access a remote cluster.
We will therefore show how to access services and pods of the remote cluster, from our local machine.
You can also run these exercises directly on the cluster (if you haven't
installed and set up kubectl locally).
Running commands locally will be less useful
(since you could access services and pods directly),
but keep in mind that these commands will work anywhere as long as you have
installed and set up kubectl to communicate with your cluster.
kubectl proxy in theory
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Running
kubectl proxygives us access to the entire Kubernetes API -
The API includes routes to proxy HTTP traffic
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These routes look like the following:
/api/v1/namespaces/<namespace>/services/<service>/proxy -
We just add the URI to the end of the request, for instance:
/api/v1/namespaces/<namespace>/services/<service>/proxy/index.html -
We can access
servicesandpodsthis way
kubectl proxy in practice
- Let's access the
webuiservice throughkubectl proxy
.exercise[
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Run an API proxy in the background:
kubectl proxy & -
Access the
webuiservice:curl localhost:8001/api/v1/namespaces/default/services/webui/proxy/index.html -
Terminate the proxy:
kill %1
]
kubectl port-forward in theory
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What if we want to access a TCP service?
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We can use
kubectl port-forwardinstead -
It will create a TCP relay to forward connections to a specific port
(of a pod, service, deployment...)
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The syntax is:
kubectl port-forward service/name_of_service local_port:remote_port -
If only one port number is specified, it is used for both local and remote ports
kubectl port-forward in practice
- Let's access our remote Redis server
.exercise[
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Forward connections from local port 10000 to remote port 6379:
kubectl port-forward svc/redis 10000:6379 & -
Connect to the Redis server:
telnet localhost 10000 -
Issue a few commands, e.g.
INFO serverthenQUIT
- Terminate the port forwarder:
kill %1
]