kmux
kmux is a tool for executing common Kubernetes actions on one or many clusters at the same time.
For example when you have multiple Kubernetes clusters you want to tail the logs of the same deployment simultaneously, or check the image deployed on each cluster.
Getting started
Release
Download the latest binary for your os and architecture from the GitHub Releases page
curl \
--disable \
--silent \
--show-error \
--location \
--max-time 300 \
"https://github.com/ViBiOh/kmux/releases/latest/download/kmux_$(uname -s | tr "[:upper:]" "[:lower:]")_$(uname -m | tr "[:upper:]" "[:lower:]" | sed "s|aarch64|arm64|").tar.gz" | tar -xz "kmux"
mv "kmux" "/usr/local/bin/kmux"
Golang
go install "github.com/ViBiOh/kmux@latest"
Shell completions
Shell completions are available by running the following command (example is for bash, but it’s available for zsh, fish and powershell).
source <(kmux completion bash)
You can also put in a dedicated file and source it from your *sh.rc
Features
Because the goal of this tool is to be used on multiple clusters at once, we rely on high-level object name (object that templatize pods, e.g. deployments, daemonset, etc.).
For running on multiple clusters at once, set the --context flag multiple times.
kmux --context central1 --context europe1 --context asia1 image
Global Flags:
-A, --all-namespaces Find resources in all namespaces
--context strings Kubernetes context, multiple for mutiplexing commands
--kubeconfig string Kubernetes configuration file (default "${HOME}/.kube/config")
-n, --namespace string Override kubernetes namespace in context
log
log command open a pod’s watcher on a resource (Deployment, Service, CronJob, etc) by using label or fiels selector and stream every container’s logs of every pod it finds. New pods matching the selector are automatically streamed. Logs are stream by default (the --follow option in regular kubectl).
Each log line has a prefix of the pod’s name and the container name, and also the context’s name if there are multiple contexts. These kind of metadatas are written to the stderr, this way, if you have logs in JSON, you can pipe kmux output into jq for example for extracting wanted data from logs (instead of using --grep or native grep). You can also remove completely the prefixes by setting --raw-output option.
If your logs are in JSON, you can also filter output based on their color:
- 🟥
red: HTTP/5xx orERROR,CRITICALorFATALlevel (case insensitive) - 🟨
yellow: HTTP/4xx orWARN[ING]level (case insensitive) - ⬜️
white: Regular log (or unidentified) - 🟩
green: HTTP/3xx orDEBUG,TRACElevel (case insensitive)
Log levels and HTTP Status codes are determined by searching for keys defined in options --statusCodeKeys and --levelKeys. The most common values are defined by default. First match of level or http status code determine the color.
The --container can be set to restrict output to the given containers’ name.
Get logs of a given resource
Usage:
kmux log TYPE NAME [flags]
Aliases:
log, logs
Flags:
-c, --container string Filter container's name by regexp, default to all containers
-d, --dry-run Dry-run, print only pods
-g, --grep strings Regexp to filter log
--grepColor string Get logs only above given color (red > yellow > green)
-v, --invert-match Invert regexp filter matching
--levelKeys strings Keys for level in JSON (default [level,severity])
--no-follow Don't follow logs
-r, --raw-output Raw ouput, don't print context or pod prefixes
-l, --selector stringToString Labels to filter pods (default [])
-s, --since duration Display logs since given duration (default 1h0m0s)
--statusCodeKeys strings Keys for HTTP Status code in JSON (default [status,statusCode,response_code,http_status,OriginStatus])
port-forward
Like log, port-forward command open a pod’s watcher on a resource and port-forward to every container matching port and being ready. New pods matching the selector are automatically streamed.
A local tcp load-balancer is started on given local port that will forward to underlying pods by using round-robin algorithm.
Port forward to pods of a resource
Usage:
kmux port-forward TYPE NAME [local_port:]remote_port [flags]
Aliases:
port-forward, forward
Flags:
-d, --dry-run Dry-run, print only pods
-l, --limit uint Limit forward to only n pods
watch
watch for all pods in a given namespace (or all namespaces). Status phase is done in a nearly same way that the official kubectl (computing the status of a Pod is not that easy).
Output is colored according to the current status of the pod, for better clarity.
Get all pods in the namespace
Usage:
kmux watch [flags]
Flags:
-L, --label-columns strings Labels that are going to be presented as columns
-o, --output string Output format. One of: (wide)
-l, --selector stringToString Labels to filter pods (default [])
--show-annotations Show all annotations as the last column (after labels if both asked)
--show-labels Show all labels as the last column
restart
restart performs the equivalent of a rollout restart on given resource (add an annotation of the pod spec). For job, it’s the equivalent of a replacement (delete then create).
Restart the given resource
Usage:
kmux restart TYPE NAME [flags]
Flags:
-u, --user string User added in the restartedBy annotation (read from $KMUX_USER)
image
image prints the image name of all containers found in given resource. The idea is to check that every cluster runs the same version.
Get all image names of containers for a given resource
Usage:
kmux image TYPE NAME [flags]
Flags:
-c, --container string Filter container's name by regexp, default to all containers
env
env prints the configured environment variables from the given resource. When a value is dynamic (e.g. hostIP, podIP, etc.), the value from the most “live” pod is retrieved.
Get all configured environment variables of containers for a given resource
Usage:
kmux env TYPE NAME [flags]
Flags:
-c, --container string Filter container's name by regexp, default to all containers