## kn service update

Update a service.

### Synopsis

Update a service.

```
kn service update NAME [flags]
```

### Examples

```

  # Updates a service 'svc' with new environment variables
  kn service update svc --env KEY1=VALUE1 --env KEY2=VALUE2

  # Update a service 'svc' with new port
  kn service update svc --port 80

  # Updates a service 'svc' with new requests and limits parameters
  kn service update svc --requests-cpu 500m --limits-memory 1024Mi

  # Assign tag 'latest' and 'stable' to revisions 'echo-v2' and 'echo-v1' respectively
  kn service update svc --tag echo-v2=latest --tag echo-v1=stable
  OR
  kn service update svc --tag echo-v2=latest,echo-v1=stable

  # Update tag from 'testing' to 'staging' for latest ready revision of service
  kn service update svc --untag testing --tag @latest=staging

  # Add tag 'test' to echo-v3 revision with 10% traffic and rest to latest ready revision of service
  kn service update svc --tag echo-v3=test --traffic test=10,@latest=90
```

### Options

```
      --annotation stringArray    Service annotation to set. name=value; you may provide this flag any number of times to set multiple annotations. To unset, specify the annotation name followed by a "-" (e.g., name-).
      --arg stringArray           Add argument to the container command. Example: --arg myArg1 --arg --myArg2 --arg myArg3=3. You can use this flag multiple times.
      --async                     DEPRECATED: please use --no-wait instead. Update service and don't wait for it to be ready.
      --autoscale-window string   Duration to look back for making auto-scaling decisions. The service is scaled to zero if no request was received in during that time. (eg: 10s)
      --cmd string                Specify command to be used as entrypoint instead of default one. Example: --cmd /app/start or --cmd /app/start --arg myArg to pass aditional arguments.
      --concurrency-limit int     Hard Limit of concurrent requests to be processed by a single replica.
      --concurrency-target int    Recommendation for when to scale up based on the concurrent number of incoming request. Defaults to --concurrency-limit when given.
  -e, --env stringArray           Environment variable to set. NAME=value; you may provide this flag any number of times to set multiple environment variables. To unset, specify the environment variable name followed by a "-" (e.g., NAME-).
      --env-from stringArray      Add environment variables from a ConfigMap (prefix cm: or config-map:) or a Secret (prefix secret:). Example: --env-from cm:myconfigmap or --env-from secret:mysecret. You can use this flag multiple times. To unset a ConfigMap/Secret reference, append "-" to the name, e.g. --env-from cm:myconfigmap-.
  -h, --help                      help for update
      --image string              Image to run.
  -l, --label stringArray         Service label to set. name=value; you may provide this flag any number of times to set multiple labels. To unset, specify the label name followed by a "-" (e.g., name-).
      --limits-cpu string         The limits on the requested CPU (e.g., 1000m).
      --limits-memory string      The limits on the requested memory (e.g., 1024Mi).
      --lock-to-digest            Keep the running image for the service constant when not explicitly specifying the image. (--no-lock-to-digest pulls the image tag afresh with each new revision) (default true)
      --max-scale int             Maximal number of replicas.
      --min-scale int             Minimal number of replicas.
      --mount stringArray         Mount a ConfigMap (prefix cm: or config-map:), a Secret (prefix secret: or sc:), or an existing Volume (without any prefix) on the specified directory. Example: --mount /mydir=cm:myconfigmap, --mount /mydir=secret:mysecret, or --mount /mydir=myvolume. When a configmap or a secret is specified, a corresponding volume is automatically generated. You can use this flag multiple times. For unmounting a directory, append "-", e.g. --mount /mydir-, which also removes any auto-generated volume.
  -n, --namespace string          Specify the namespace to operate in.
      --no-lock-to-digest         Do not keep the running image for the service constant when not explicitly specifying the image. (--no-lock-to-digest pulls the image tag afresh with each new revision)
      --no-wait                   Update service and don't wait for it to be ready.
  -p, --port int32                The port where application listens on.
      --pull-secret string        Image pull secret to set. An empty argument ("") clears the pull secret. The referenced secret must exist in the service's namespace.
      --requests-cpu string       The requested CPU (e.g., 250m).
      --requests-memory string    The requested memory (e.g., 64Mi).
      --revision-name string      The revision name to set. Must start with the service name and a dash as a prefix. Empty revision name will result in the server generating a name for the revision. Accepts golang templates, allowing {{.Service}} for the service name, {{.Generation}} for the generation, and {{.Random [n]}} for n random consonants. (default "{{.Service}}-{{.Random 5}}-{{.Generation}}")
      --service-account string    Service account name to set. An empty argument ("") clears the service account. The referenced service account must exist in the service's namespace.
      --tag strings               Set tag (format: --tag revisionRef=tagName) where revisionRef can be a revision or '@latest' string representing latest ready revision. This flag can be specified multiple times.
      --traffic strings           Set traffic distribution (format: --traffic revisionRef=percent) where revisionRef can be a revision or a tag or '@latest' string representing latest ready revision. This flag can be given multiple times with percent summing up to 100%.
      --untag strings             Untag revision (format: --untag tagName). This flag can be specified multiple times.
      --user int                  The user ID to run the container (e.g., 1001).
      --volume stringArray        Add a volume from a ConfigMap (prefix cm: or config-map:) or a Secret (prefix secret: or sc:). Example: --volume myvolume=cm:myconfigmap or --volume myvolume=secret:mysecret. You can use this flag multiple times. To unset a ConfigMap/Secret reference, append "-" to the name, e.g. --volume myvolume-.
      --wait-timeout int          Seconds to wait before giving up on waiting for service to be ready. (default 600)
```

### Options inherited from parent commands

```
      --config string       kn config file (default is ~/.config/kn/config.yaml)
      --kubeconfig string   kubectl config file (default is ~/.kube/config)
      --log-http            log http traffic
```

### SEE ALSO

* [kn service](kn_service.md)	 - Service command group