kubectl-tmux-exec

A kubectl plugin for executing commands interactively across multiple pods or containers using tmux, like csshX or pssh but for Kubernetes.

To execute command across all the Nginx containers using bash for example, run:

kubectl tmux-exec -l app=nginx /bin/bash

Installation

Homebrew

Note: This is for Mac users only.

1. Install Homebrew.

2. brew install predatorray/brew/kubectl-tmux-exec

Finally, ensure /usr/local/bin/kubectl-tmux_exec is in your $PATH.

Krew

Note: It is recommended for Linux users.

Although it works both on Mac and Linux, it is not recommended for Mac users, since you still may need to install the dependency gnu-getopt with the help of Homebrew.

1. Install Krew by following the user guide.

2. kubectl krew install tmux-exec

3. Install the dependencies. (Wiki: How-to-Install-Dependencies)

Manually

1. Download the latest release.

2. Unpack the kubectl-tmux-exec-*.tar.gz file and copy all the files to a directory, /usr/local/kubectl-tmux-exec for instance.

3. Add the bin/ directory to your $PATH. For example, add this line to your rc file: export PATH="$PATH:/usr/local/kubectl-tmux-exec/bin".

4. Install the dependencies. (Wiki: How-to-Install-Dependencies)

Usage

Make sure you have kubectl ≥ 1.12 (plugin support), ideally latest.

Otherwise, execute the script directly: kubectl-tmux_exec [...ARGS].

Check if the script has been successfully added by:

kubectl plugin list

The output should be like

The following compatible plugins are available:

/usr/local/bin/kubectl-tmux_exec

If it does not show in the list, check $PATH env again.

You can use the command below to get the usage of the script.

kubectl tmux-exec --help

# or
kubectl-tmux_exec --help

Options

Flag	Usage
-V --version	Print the version information
-l --selector	Selector (label query) to filter on, supports '=', '==', and '!='.(e.g. -l key1=value1,key2=value2) You must either use --selector or --file option.
-f --file	Read pod names line-by-line from a file. You must either use --selector or --file option.
-c --container	Container name. If omitted, the first container in the pod will be chosen
-i --stdin	Pass stdin to the container (deprecated, since it's enabled by default)
-t --tty	Stdin is a TTY (deprecated, since it's enabled by default)
-d --detach	Make the Tmux session detached
-n --namespace=	The namespace scope for this CLI request (can be applied multiple times)
--context	The name of the kubeconfig context to use (can be applied multiple times)
-A --all-namespaces	If present, list and execute the requested object(s) across all namespaces. Namespace in current context is ignored even if specified with --namespace.
-C --enable-control-mode	Start tmux in control mode and echo is disabled. (See: iTerm2 Integration)
--remain-on-exit	Remain Tmux window on exit
--select-layout	One of the five Tmux preset layouts: even-horizontal, even-vertical, main-horizontal, main-vertical, or tiled.
--session-mode	Where tmux is opened: auto, new-session, current-session

The usage of these options is also available by --help.

Example

The tmux-exec is similar to exec, except that it requires label selectors while exec requires a pod name.

To bash into all pod containers that share some common labels, foo=bar for instance.

kubectl tmux-exec -l foo=bar /bin/bash

After you have successfully bash-ed into your selected containers, a Tmux window is opened actually, where each pane displays the execution result of each pod's container. Your keyboard inputs will be synchronized to all those panes.

If you are not familar with Tmux, you can have a look at tmux's man page or online tutorials. Or you can see the cheatsheet below, which will be sufficient I think.

iTerm2 Integration

With -C or --enable-control-mode, it runs in control mode and delegates pane input to iTerm2's "Broadcast Input" feature, no need for tmux key bindings.

Use ⌘ + ⌥ + i to toggle broadcasting in iTerm2. (synchronize-panes will be disabled automatically in this mode.)

(see: tmux Integration for more information)

Example

kubectl tmux-exec -C -l app=nginx /bin/bash

Shell Auto-completion

Please check this wiki for more information.

Tmux Cheatsheet

All Tmux command starts with a PREFIX. By default the PREFIX is Ctrl + b. I will use C-b below to stand for it.

C-b d, detach from the session. After that, the Tmux will be running in the backgroud. You can type tmux a to re-attach.

C-b :setw synchronize-panes off, turn off synchronizing inputs to all panes.

C-b :setw synchronize-panes on, turn on synchronizing inputs to all panes.

C-b <ARROW-KEY>, move cursor between panes.

C-b xy, close the current pane.

C-b &y, close the window including all panes.

Community & Support

• File issues or feature requests via GitHub Issues
• Join the Google Group for discussions

Other plugins

kubectl-alias: the missing alias command for kubectl.

Buy Me a Coffee

If it saves you time, feel free to buy me a coffee 🙌