---
WARNING: THIS IS AN AUTO-GENERATED FILE, DO NOT EDIT. PLEASE MODIFY THE ORIGINAL SOURCE IN THE 'https://github.com/istio/istio' REPO
source_repo: https://github.com/istio/istio
title: istio_ca
description: Istio Certificate Authority (CA).
generator: pkg-collateral-docs
number_of_entries: 4
---
<p>Istio Certificate Authority (CA).</p>
<pre class="language-bash"><code>istio_ca [flags]
</code></pre>
<table class="command-flags">
<thead>
<tr>
<th>Flags</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>--append-dns-names</code></td>
<td>Append DNS names to the certificates for webhook services. </td>
</tr>
<tr>
<td><code>--cert-chain &lt;string&gt;</code></td>
<td>Path to the certificate chain file.  (default ``)</td>
</tr>
<tr>
<td><code>--citadel-storage-namespace &lt;string&gt;</code></td>
<td>Namespace where the Citadel pod is running. Will not be used if explicit file or other storage mechanism is specified.  (default `istio-system`)</td>
</tr>
<tr>
<td><code>--ctrlz_address &lt;string&gt;</code></td>
<td>The IP Address to listen on for the ControlZ introspection facility. Use &#39;*&#39; to indicate all addresses.  (default `localhost`)</td>
</tr>
<tr>
<td><code>--ctrlz_port &lt;uint16&gt;</code></td>
<td>The IP port to use for the ControlZ introspection facility  (default `9876`)</td>
</tr>
<tr>
<td><code>--custom-dns-names &lt;string&gt;</code></td>
<td>The list of account.namespace:customdns names, separated by comma.  (default ``)</td>
</tr>
<tr>
<td><code>--enable-profiling</code></td>
<td>Enabling profiling when monitoring Citadel. </td>
</tr>
<tr>
<td><code>--experimental-dual-use</code></td>
<td>Enable dual-use mode. Generates certificates with a CommonName identical to the SAN. </td>
</tr>
<tr>
<td><code>--grpc-host-identities &lt;string&gt;</code></td>
<td>The list of hostnames for istio ca server, separated by comma.  (default `istio-ca,istio-citadel`)</td>
</tr>
<tr>
<td><code>--grpc-port &lt;int&gt;</code></td>
<td>The port number for Citadel GRPC server. If unspecified, Citadel will not serve GRPC requests.  (default `8060`)</td>
</tr>
<tr>
<td><code>--key-size &lt;int&gt;</code></td>
<td>Size of generated private key.  (default `2048`)</td>
</tr>
<tr>
<td><code>--kube-config &lt;string&gt;</code></td>
<td>Specifies path to kubeconfig file. This must be specified when not running inside a Kubernetes pod.  (default ``)</td>
</tr>
<tr>
<td><code>--listened-namespaces &lt;string&gt;</code></td>
<td>Select the namespaces for the Citadel to listen to, separated by comma. If unspecified, Citadel tries to use the ${NAMESPACE} environment variable. If neither is set, Citadel listens to all namespaces.  (default ``)</td>
</tr>
<tr>
<td><code>--liveness-probe-interval &lt;duration&gt;</code></td>
<td>Interval of updating file for the liveness probe.  (default `0s`)</td>
</tr>
<tr>
<td><code>--liveness-probe-path &lt;string&gt;</code></td>
<td>Path to the file for the liveness probe.  (default ``)</td>
</tr>
<tr>
<td><code>--log_as_json</code></td>
<td>Whether to format output as JSON or in plain console-friendly format </td>
</tr>
<tr>
<td><code>--log_caller &lt;string&gt;</code></td>
<td>Comma-separated list of scopes for which to include caller information, scopes can be any of [all, default, monitor]  (default ``)</td>
</tr>
<tr>
<td><code>--log_output_level &lt;string&gt;</code></td>
<td>Comma-separated minimum per-scope logging level of messages to output, in the form of &lt;scope&gt;:&lt;level&gt;,&lt;scope&gt;:&lt;level&gt;,... where scope can be one of [all, default, monitor] and level can be one of [debug, info, warn, error, fatal, none]  (default `default:info`)</td>
</tr>
<tr>
<td><code>--log_rotate &lt;string&gt;</code></td>
<td>The path for the optional rotating log file  (default ``)</td>
</tr>
<tr>
<td><code>--log_rotate_max_age &lt;int&gt;</code></td>
<td>The maximum age in days of a log file beyond which the file is rotated (0 indicates no limit)  (default `30`)</td>
</tr>
<tr>
<td><code>--log_rotate_max_backups &lt;int&gt;</code></td>
<td>The maximum number of log file backups to keep before older files are deleted (0 indicates no limit)  (default `1000`)</td>
</tr>
<tr>
<td><code>--log_rotate_max_size &lt;int&gt;</code></td>
<td>The maximum size in megabytes of a log file beyond which the file is rotated  (default `104857600`)</td>
</tr>
<tr>
<td><code>--log_stacktrace_level &lt;string&gt;</code></td>
<td>Comma-separated minimum per-scope logging level at which stack traces are captured, in the form of &lt;scope&gt;:&lt;level&gt;,&lt;scope:level&gt;,... where scope can be one of [all, default, monitor] and level can be one of [debug, info, warn, error, fatal, none]  (default `default:none`)</td>
</tr>
<tr>
<td><code>--log_target &lt;stringArray&gt;</code></td>
<td>The set of paths where to output the log. This can be any path as well as the special values stdout and stderr  (default `[stdout]`)</td>
</tr>
<tr>
<td><code>--max-workload-cert-ttl &lt;duration&gt;</code></td>
<td>The max TTL of issued workload certificates.  (default `2160h0m0s`)</td>
</tr>
<tr>
<td><code>--monitoring-port &lt;int&gt;</code></td>
<td>The port number for monitoring Citadel. If unspecified, Citadel will disable monitoring.  (default `15014`)</td>
</tr>
<tr>
<td><code>--org &lt;string&gt;</code></td>
<td>Organization for the certificate.  (default ``)</td>
</tr>
<tr>
<td><code>--pkcs8-keys</code></td>
<td>Whether to generate PKCS#8 private keys. </td>
</tr>
<tr>
<td><code>--probe-check-interval &lt;duration&gt;</code></td>
<td>Interval of checking the liveness of the CA.  (default `30s`)</td>
</tr>
<tr>
<td><code>--read-signing-cert-only</code></td>
<td>When set, Citadel only reads the self-signed signing key and cert from Kubernetes secret without generating one (if not exist). This flag avoids racing condition between multiple Citadels generating self-signed key and cert. Please make sure one and only one Citadel instance has this flag set to false. </td>
</tr>
<tr>
<td><code>--requested-ca-cert-ttl &lt;duration&gt;</code></td>
<td>The requested TTL for the CA certificate.  (default `8760h0m0s`)</td>
</tr>
<tr>
<td><code>--root-cert &lt;string&gt;</code></td>
<td>Path to the root certificate file.  (default ``)</td>
</tr>
<tr>
<td><code>--sds-enabled</code></td>
<td>Whether SDS is enabled. </td>
</tr>
<tr>
<td><code>--self-signed-ca</code></td>
<td>Indicates whether to use auto-generated self-signed CA certificate. When set to true, the &#39;--signing-cert&#39; and &#39;--signing-key&#39; options are ignored. </td>
</tr>
<tr>
<td><code>--self-signed-ca-cert-ttl &lt;duration&gt;</code></td>
<td>The TTL of self-signed CA root certificate.  (default `87600h0m0s`)</td>
</tr>
<tr>
<td><code>--server-only</code></td>
<td>When set, Citadel only serves as a server without writing the Kubernetes secrets. </td>
</tr>
<tr>
<td><code>--sign-ca-certs</code></td>
<td>Whether Citadel signs certificates for other CAs. </td>
</tr>
<tr>
<td><code>--signing-cert &lt;string&gt;</code></td>
<td>Path to the CA signing certificate file.  (default ``)</td>
</tr>
<tr>
<td><code>--signing-key &lt;string&gt;</code></td>
<td>Path to the CA signing key file.  (default ``)</td>
</tr>
<tr>
<td><code>--trust-domain &lt;string&gt;</code></td>
<td>The domain serves to identify the system with SPIFFE.  (default ``)</td>
</tr>
<tr>
<td><code>--upstream-ca-address &lt;string&gt;</code></td>
<td>The IP:port address of the upstream CA. When set, the CA will rely on the upstream Citadel to provision its own certificate.  (default ``)</td>
</tr>
<tr>
<td><code>--workload-cert-grace-period-ratio &lt;float32&gt;</code></td>
<td>The workload certificate rotation grace period, as a ratio of the workload certificate TTL.  (default `0.5`)</td>
</tr>
<tr>
<td><code>--workload-cert-min-grace-period &lt;duration&gt;</code></td>
<td>The minimum workload certificate rotation grace period.  (default `10m0s`)</td>
</tr>
<tr>
<td><code>--workload-cert-ttl &lt;duration&gt;</code></td>
<td>The TTL of issued workload certificates.  (default `2160h0m0s`)</td>
</tr>
</tbody>
</table>
<h2 id="istio_ca-probe">istio_ca probe</h2>
<p>Check the liveness or readiness of a locally-running server</p>
<pre class="language-bash"><code>istio_ca probe [flags]
</code></pre>
<table class="command-flags">
<thead>
<tr>
<th>Flags</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>--ctrlz_address &lt;string&gt;</code></td>
<td>The IP Address to listen on for the ControlZ introspection facility. Use &#39;*&#39; to indicate all addresses.  (default `localhost`)</td>
</tr>
<tr>
<td><code>--ctrlz_port &lt;uint16&gt;</code></td>
<td>The IP port to use for the ControlZ introspection facility  (default `9876`)</td>
</tr>
<tr>
<td><code>--interval &lt;duration&gt;</code></td>
<td>Duration used for checking the target file&#39;s last modified time.  (default `0s`)</td>
</tr>
<tr>
<td><code>--log_as_json</code></td>
<td>Whether to format output as JSON or in plain console-friendly format </td>
</tr>
<tr>
<td><code>--log_caller &lt;string&gt;</code></td>
<td>Comma-separated list of scopes for which to include caller information, scopes can be any of [all, default, monitor]  (default ``)</td>
</tr>
<tr>
<td><code>--log_output_level &lt;string&gt;</code></td>
<td>Comma-separated minimum per-scope logging level of messages to output, in the form of &lt;scope&gt;:&lt;level&gt;,&lt;scope&gt;:&lt;level&gt;,... where scope can be one of [all, default, monitor] and level can be one of [debug, info, warn, error, fatal, none]  (default `default:info`)</td>
</tr>
<tr>
<td><code>--log_rotate &lt;string&gt;</code></td>
<td>The path for the optional rotating log file  (default ``)</td>
</tr>
<tr>
<td><code>--log_rotate_max_age &lt;int&gt;</code></td>
<td>The maximum age in days of a log file beyond which the file is rotated (0 indicates no limit)  (default `30`)</td>
</tr>
<tr>
<td><code>--log_rotate_max_backups &lt;int&gt;</code></td>
<td>The maximum number of log file backups to keep before older files are deleted (0 indicates no limit)  (default `1000`)</td>
</tr>
<tr>
<td><code>--log_rotate_max_size &lt;int&gt;</code></td>
<td>The maximum size in megabytes of a log file beyond which the file is rotated  (default `104857600`)</td>
</tr>
<tr>
<td><code>--log_stacktrace_level &lt;string&gt;</code></td>
<td>Comma-separated minimum per-scope logging level at which stack traces are captured, in the form of &lt;scope&gt;:&lt;level&gt;,&lt;scope:level&gt;,... where scope can be one of [all, default, monitor] and level can be one of [debug, info, warn, error, fatal, none]  (default `default:none`)</td>
</tr>
<tr>
<td><code>--log_target &lt;stringArray&gt;</code></td>
<td>The set of paths where to output the log. This can be any path as well as the special values stdout and stderr  (default `[stdout]`)</td>
</tr>
<tr>
<td><code>--probe-path &lt;string&gt;</code></td>
<td>Path of the file for checking the availability.  (default ``)</td>
</tr>
</tbody>
</table>
<h2 id="istio_ca-version">istio_ca version</h2>
<p>Prints out build version information</p>
<pre class="language-bash"><code>istio_ca version [flags]
</code></pre>
<table class="command-flags">
<thead>
<tr>
<th>Flags</th>
<th>Shorthand</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>--ctrlz_address &lt;string&gt;</code></td>
<td></td>
<td>The IP Address to listen on for the ControlZ introspection facility. Use &#39;*&#39; to indicate all addresses.  (default `localhost`)</td>
</tr>
<tr>
<td><code>--ctrlz_port &lt;uint16&gt;</code></td>
<td></td>
<td>The IP port to use for the ControlZ introspection facility  (default `9876`)</td>
</tr>
<tr>
<td><code>--log_as_json</code></td>
<td></td>
<td>Whether to format output as JSON or in plain console-friendly format </td>
</tr>
<tr>
<td><code>--log_caller &lt;string&gt;</code></td>
<td></td>
<td>Comma-separated list of scopes for which to include caller information, scopes can be any of [all, default, monitor]  (default ``)</td>
</tr>
<tr>
<td><code>--log_output_level &lt;string&gt;</code></td>
<td></td>
<td>Comma-separated minimum per-scope logging level of messages to output, in the form of &lt;scope&gt;:&lt;level&gt;,&lt;scope&gt;:&lt;level&gt;,... where scope can be one of [all, default, monitor] and level can be one of [debug, info, warn, error, fatal, none]  (default `default:info`)</td>
</tr>
<tr>
<td><code>--log_rotate &lt;string&gt;</code></td>
<td></td>
<td>The path for the optional rotating log file  (default ``)</td>
</tr>
<tr>
<td><code>--log_rotate_max_age &lt;int&gt;</code></td>
<td></td>
<td>The maximum age in days of a log file beyond which the file is rotated (0 indicates no limit)  (default `30`)</td>
</tr>
<tr>
<td><code>--log_rotate_max_backups &lt;int&gt;</code></td>
<td></td>
<td>The maximum number of log file backups to keep before older files are deleted (0 indicates no limit)  (default `1000`)</td>
</tr>
<tr>
<td><code>--log_rotate_max_size &lt;int&gt;</code></td>
<td></td>
<td>The maximum size in megabytes of a log file beyond which the file is rotated  (default `104857600`)</td>
</tr>
<tr>
<td><code>--log_stacktrace_level &lt;string&gt;</code></td>
<td></td>
<td>Comma-separated minimum per-scope logging level at which stack traces are captured, in the form of &lt;scope&gt;:&lt;level&gt;,&lt;scope:level&gt;,... where scope can be one of [all, default, monitor] and level can be one of [debug, info, warn, error, fatal, none]  (default `default:none`)</td>
</tr>
<tr>
<td><code>--log_target &lt;stringArray&gt;</code></td>
<td></td>
<td>The set of paths where to output the log. This can be any path as well as the special values stdout and stderr  (default `[stdout]`)</td>
</tr>
<tr>
<td><code>--output &lt;string&gt;</code></td>
<td><code>-o</code></td>
<td>One of &#39;yaml&#39; or &#39;json&#39;.  (default ``)</td>
</tr>
<tr>
<td><code>--short</code></td>
<td><code>-s</code></td>
<td>Use --short=false to generate full version information </td>
</tr>
</tbody>
</table>
<h2 id="envvars">Environment variables</h2>
These environment variables affect the behavior of the <code>istio_ca</code> command.
<table class="envvars">
<thead>
<tr>
<th>Variable Name</th>
<th>Type</th>
<th>Default Value</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>CITADEL_ENABLE_NAMESPACES_BY_DEFAULT</code></td>
<td>Boolean</td>
<td><code>true</code></td>
<td>Determines whether unlabeled namespaces should be targeted by this Citadel instance</td>
</tr>
<tr>
<td><code>NAMESPACE</code></td>
<td>String</td>
<td><code></code></td>
<td></td>
</tr>
</tbody>
</table>
<h2 id="metrics">Exported metrics</h2>
<table class="metrics">
<thead>
<tr><th>Metric Name</th><th>Type</th><th>Description</th></tr>
</thead>
<tbody>
<tr><td><code>citadel_secret_controller_csr_err_count</code></td><td><code>Sum</code></td><td>The number of errors occurred when creating the CSR.</td></tr>
<tr><td><code>citadel_secret_controller_csr_sign_err_count</code></td><td><code>Sum</code></td><td>The number of errors occurred when signing the CSR.</td></tr>
<tr><td><code>citadel_secret_controller_secret_deleted_cert_count</code></td><td><code>Sum</code></td><td>The number of certificates recreated due to secret deletion (service account still exists).</td></tr>
<tr><td><code>citadel_secret_controller_svc_acc_created_cert_count</code></td><td><code>Sum</code></td><td>The number of certificates created due to service account creation.</td></tr>
<tr><td><code>citadel_secret_controller_svc_acc_deleted_cert_count</code></td><td><code>Sum</code></td><td>The number of certificates deleted due to service account deletion.</td></tr>
<tr><td><code>citadel_server_authentication_failure_count</code></td><td><code>Sum</code></td><td>The number of authentication failures.</td></tr>
<tr><td><code>citadel_server_csr_count</code></td><td><code>Sum</code></td><td>The number of CSRs received by Citadel server.</td></tr>
<tr><td><code>citadel_server_csr_parsing_err_count</code></td><td><code>Sum</code></td><td>The number of errors occurred when parsing the CSR.</td></tr>
<tr><td><code>citadel_server_csr_sign_err_count</code></td><td><code>Sum</code></td><td>The number of errors occurred when signing the CSR.</td></tr>
<tr><td><code>citadel_server_id_extraction_err_count</code></td><td><code>Sum</code></td><td>The number of errors occurred when extracting the ID from CSR.</td></tr>
<tr><td><code>citadel_server_root_cert_expiry_timestamp</code></td><td><code>LastValue</code></td><td>The unix timestamp, in seconds, when Citadel root cert will expire. We set it to negative in case of internal error.</td></tr>
<tr><td><code>citadel_server_success_cert_issuance_count</code></td><td><code>Sum</code></td><td>The number of certificates issuances that have succeeded.</td></tr>
<tr><td><code>istio_build</code></td><td><code>LastValue</code></td><td>Istio component build info</td></tr>
</tbody>
</table>