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[ aws . ec2 ]



Modifies the specified Client VPN endpoint. Modifying the DNS server resets existing client connections.

See also: AWS API Documentation


--client-vpn-endpoint-id <value>
[--server-certificate-arn <value>]
[--connection-log-options <value>]
[--dns-servers <value>]
[--vpn-port <value>]
[--description <value>]
[--split-tunnel | --no-split-tunnel]
[--dry-run | --no-dry-run]
[--security-group-ids <value>]
[--vpc-id <value>]
[--self-service-portal <value>]
[--client-connect-options <value>]
[--session-timeout-hours <value>]
[--client-login-banner-options <value>]
[--cli-input-json <value>]
[--generate-cli-skeleton <value>]
[--endpoint-url <value>]
[--output <value>]
[--query <value>]
[--profile <value>]
[--region <value>]
[--version <value>]
[--color <value>]
[--ca-bundle <value>]
[--cli-read-timeout <value>]
[--cli-connect-timeout <value>]


--client-vpn-endpoint-id (string)

The ID of the Client VPN endpoint to modify.

--server-certificate-arn (string)

The ARN of the server certificate to be used. The server certificate must be provisioned in Certificate Manager (ACM).

--connection-log-options (structure)

Information about the client connection logging options.

If you enable client connection logging, data about client connections is sent to a Cloudwatch Logs log stream. The following information is logged:

  • Client connection requests
  • Client connection results (successful and unsuccessful)
  • Reasons for unsuccessful client connection requests
  • Client connection termination time

Enabled -> (boolean)

Indicates whether connection logging is enabled.

CloudwatchLogGroup -> (string)

The name of the CloudWatch Logs log group. Required if connection logging is enabled.

CloudwatchLogStream -> (string)

The name of the CloudWatch Logs log stream to which the connection data is published.

Shorthand Syntax:


JSON Syntax:

  "Enabled": true|false,
  "CloudwatchLogGroup": "string",
  "CloudwatchLogStream": "string"

--dns-servers (structure)

Information about the DNS servers to be used by Client VPN connections. A Client VPN endpoint can have up to two DNS servers.

CustomDnsServers -> (list)

The IPv4 address range, in CIDR notation, of the DNS servers to be used. You can specify up to two DNS servers. Ensure that the DNS servers can be reached by the clients. The specified values overwrite the existing values.


Enabled -> (boolean)

Indicates whether DNS servers should be used. Specify False to delete the existing DNS servers.

Shorthand Syntax:


JSON Syntax:

  "CustomDnsServers": ["string", ...],
  "Enabled": true|false

--vpn-port (integer)

The port number to assign to the Client VPN endpoint for TCP and UDP traffic.

Valid Values: 443 | 1194

Default Value: 443

--description (string)

A brief description of the Client VPN endpoint.

--split-tunnel | --no-split-tunnel (boolean)

Indicates whether the VPN is split-tunnel.

For information about split-tunnel VPN endpoints, see Split-tunnel Client VPN endpoint in the Client VPN Administrator Guide .

--dry-run | --no-dry-run (boolean)

Checks whether you have the required permissions for the action, without actually making the request, and provides an error response. If you have the required permissions, the error response is DryRunOperation . Otherwise, it is UnauthorizedOperation .

--security-group-ids (list)

The IDs of one or more security groups to apply to the target network.



"string" "string" ...

--vpc-id (string)

The ID of the VPC to associate with the Client VPN endpoint.

--self-service-portal (string)

Specify whether to enable the self-service portal for the Client VPN endpoint.

Possible values:

  • enabled
  • disabled

--client-connect-options (structure)

The options for managing connection authorization for new client connections.

Enabled -> (boolean)

Indicates whether client connect options are enabled. The default is false (not enabled).

LambdaFunctionArn -> (string)

The Amazon Resource Name (ARN) of the Lambda function used for connection authorization.

Shorthand Syntax:


JSON Syntax:

  "Enabled": true|false,
  "LambdaFunctionArn": "string"

--session-timeout-hours (integer)

The maximum VPN session duration time in hours.

Valid values: 8 | 10 | 12 | 24

Default value: 24

--client-login-banner-options (structure)

Options for enabling a customizable text banner that will be displayed on Amazon Web Services provided clients when a VPN session is established.

Enabled -> (boolean)

Enable or disable a customizable text banner that will be displayed on Amazon Web Services provided clients when a VPN session is established.

Valid values: true | false

Default value: false

BannerText -> (string)

Customizable text that will be displayed in a banner on Amazon Web Services provided clients when a VPN session is established. UTF-8 encoded characters only. Maximum of 1400 characters.

Shorthand Syntax:


JSON Syntax:

  "Enabled": true|false,
  "BannerText": "string"

--cli-input-json (string) Performs service operation based on the JSON string provided. The JSON string follows the format provided by --generate-cli-skeleton. If other arguments are provided on the command line, the CLI values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally.

--generate-cli-skeleton (string) Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value input, prints a sample input JSON that can be used as an argument for --cli-input-json. If provided with the value output, it validates the command inputs and returns a sample output JSON for that command.

Global Options

--debug (boolean)

Turn on debug logging.

--endpoint-url (string)

Override command's default URL with the given URL.

--no-verify-ssl (boolean)

By default, the AWS CLI uses SSL when communicating with AWS services. For each SSL connection, the AWS CLI will verify SSL certificates. This option overrides the default behavior of verifying SSL certificates.

--no-paginate (boolean)

Disable automatic pagination.

--output (string)

The formatting style for command output.

  • json
  • text
  • table

--query (string)

A JMESPath query to use in filtering the response data.

--profile (string)

Use a specific profile from your credential file.

--region (string)

The region to use. Overrides config/env settings.

--version (string)

Display the version of this tool.

--color (string)

Turn on/off color output.

  • on
  • off
  • auto

--no-sign-request (boolean)

Do not sign requests. Credentials will not be loaded if this argument is provided.

--ca-bundle (string)

The CA certificate bundle to use when verifying SSL certificates. Overrides config/env settings.

--cli-read-timeout (int)

The maximum socket read time in seconds. If the value is set to 0, the socket read will be blocking and not timeout. The default value is 60 seconds.

--cli-connect-timeout (int)

The maximum socket connect time in seconds. If the value is set to 0, the socket connect will be blocking and not timeout. The default value is 60 seconds.



To use the following examples, you must have the AWS CLI installed and configured. See the Getting started guide in the AWS CLI User Guide for more information.

Unless otherwise stated, all examples have unix-like quotation rules. These examples will need to be adapted to your terminal's quoting rules. See Using quotation marks with strings in the AWS CLI User Guide .

To modify a Client VPN endpoint

The following modify-client-vpn-endpoint example enables client connection logging for the specified Client VPN endpoint.

aws ec2 modify-client-vpn-endpoint \
    --client-vpn-endpoint-id cvpn-endpoint-123456789123abcde \
    --connection-log-options Enabled=true,CloudwatchLogGroup=ClientVPNLogs


    "Return": true

For more information, see Client VPN Endpoints in the AWS Client VPN Administrator Guide.


Return -> (boolean)

Returns true if the request succeeds; otherwise, it returns an error.