diff --git a/docs/content/dns/_index.md b/docs/content/dns/_index.md
index d4a80a51..7078e411 100644
--- a/docs/content/dns/_index.md
+++ b/docs/content/dns/_index.md
@@ -5,14 +5,51 @@ draft: false
 weight: 3
 ---
 
-Credentials for DNS providers must be passed through environment variables.
+## Configuration and Credentials
+
+Credentials and DNS configuration for DNS providers must be passed through environment variables.
+
+### Environment Variables: Value
+
+The environment variables can reference a value.
 
 Here is an example bash command using the CloudFlare DNS provider:
 
 ```bash
-CLOUDFLARE_EMAIL=foo@bar.com \
+$ CLOUDFLARE_EMAIL=foo@bar.com \
 CLOUDFLARE_API_KEY=b9841238feb177a84330febba8a83208921177bffe733 \
 lego --dns cloudflare --domains www.example.com --email me@bar.com run
 ```
 
+### Environment Variables: File
+
+The environment variables can reference a path to file.
+
+In this case the name of environment variable must be suffixed by `_FILE`.
+
+{{% notice note %}}
+The file must contain only the value.
+{{% /notice %}}
+
+Here is an example bash command using the CloudFlare DNS provider:
+
+```bash
+$ cat /the/path/to/my/key
+b9841238feb177a84330febba8a83208921177bffe733
+
+$ cat /the/path/to/my/email
+foo@bar.com
+
+$ CLOUDFLARE_EMAIL_FILE=/the/path/to/my/email \
+CLOUDFLARE_API_KEY=/the/path/to/my/key \
+lego --dns cloudflare --domains www.example.com --email me@bar.com run
+```
+
+## Experimental Features
+
+To resolve CNAME when creating dns-01 challenge:
+set `LEGO_EXPERIMENTAL_CNAME_SUPPORT` to `true`.
+
+## DNS Providers
+
 {{%children style="h2" description="true" %}}
\ No newline at end of file
diff --git a/docs/content/dns/zz_gen_acme-dns.md b/docs/content/dns/zz_gen_acme-dns.md
index ed671b45..61663897 100644
--- a/docs/content/dns/zz_gen_acme-dns.md
+++ b/docs/content/dns/zz_gen_acme-dns.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `ACME_DNS_API_BASE` | The ACME-DNS API address |
 | `ACME_DNS_STORAGE_PATH` | The ACME-DNS JSON account data file. A per-domain account will be registered/persisted to this file and used for TXT updates. |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_alidns.md b/docs/content/dns/zz_gen_alidns.md
index 0b1ae6fa..f8bf5c8c 100644
--- a/docs/content/dns/zz_gen_alidns.md
+++ b/docs/content/dns/zz_gen_alidns.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `ALICLOUD_ACCESS_KEY` | Access key ID |
 | `ALICLOUD_SECRET_KEY` | Access Key secret |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `ALICLOUD_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `ALICLOUD_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_auroradns.md b/docs/content/dns/zz_gen_auroradns.md
index 223819bb..fb648df7 100644
--- a/docs/content/dns/zz_gen_auroradns.md
+++ b/docs/content/dns/zz_gen_auroradns.md
@@ -32,6 +32,9 @@ _Please contribute by adding a CLI example._
 | `AURORA_KEY` | User API key |
 | `AURORA_USER_ID` | User ID |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `AURORA_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `AURORA_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_azure.md b/docs/content/dns/zz_gen_azure.md
index 4186dc87..f0d622de 100644
--- a/docs/content/dns/zz_gen_azure.md
+++ b/docs/content/dns/zz_gen_azure.md
@@ -35,6 +35,9 @@ _Please contribute by adding a CLI example._
 | `AZURE_TENANT_ID` | Tenant ID |
 | `instance metadata service` | If the credentials are **not** set via the environment, then it will attempt to get a bearer token via the [instance metadata service](https://docs.microsoft.com/en-us/azure/virtual-machines/windows/instance-metadata-service). |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -45,6 +48,9 @@ _Please contribute by adding a CLI example._
 | `AZURE_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `AZURE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_bluecat.md b/docs/content/dns/zz_gen_bluecat.md
index 64d7082d..c6ffd30d 100644
--- a/docs/content/dns/zz_gen_bluecat.md
+++ b/docs/content/dns/zz_gen_bluecat.md
@@ -34,6 +34,9 @@ _Please contribute by adding a CLI example._
 | `BLUECAT_SERVER_URL` | The server URL, should have scheme, hostname, and port (if required) of the authoritative Bluecat BAM serve |
 | `BLUECAT_USER_NAME` | API username |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -44,6 +47,9 @@ _Please contribute by adding a CLI example._
 | `BLUECAT_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `BLUECAT_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_cloudflare.md b/docs/content/dns/zz_gen_cloudflare.md
index 34868c8a..e2589d57 100644
--- a/docs/content/dns/zz_gen_cloudflare.md
+++ b/docs/content/dns/zz_gen_cloudflare.md
@@ -35,6 +35,9 @@ lego --dns cloudflare --domains my.domain.com --email my@email.com run
 | `CLOUDFLARE_API_KEY` | API key |
 | `CLOUDFLARE_EMAIL` | Account email |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -45,6 +48,9 @@ lego --dns cloudflare --domains my.domain.com --email my@email.com run
 | `CLOUDFLARE_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `CLOUDFLARE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_cloudns.md b/docs/content/dns/zz_gen_cloudns.md
index 6b5f14a9..ffcc329a 100644
--- a/docs/content/dns/zz_gen_cloudns.md
+++ b/docs/content/dns/zz_gen_cloudns.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `CLOUDNS_AUTH_ID` | The API user ID |
 | `CLOUDNS_AUTH_PASSWORD` | The password for API user ID |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `CLOUDNS_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `CLOUDNS_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_cloudxns.md b/docs/content/dns/zz_gen_cloudxns.md
index d89a5c5e..1446387f 100644
--- a/docs/content/dns/zz_gen_cloudxns.md
+++ b/docs/content/dns/zz_gen_cloudxns.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `CLOUDXNS_API_KEY` | The API key |
 | `CLOUDXNS_SECRET_KEY` | THe API secret key |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `CLOUDXNS_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `CLOUDXNS_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_conoha.md b/docs/content/dns/zz_gen_conoha.md
index c37e245f..65ef1478 100644
--- a/docs/content/dns/zz_gen_conoha.md
+++ b/docs/content/dns/zz_gen_conoha.md
@@ -32,6 +32,9 @@ _Please contribute by adding a CLI example._
 | `CONOHA_API_USERNAME` | The API username |
 | `CONOHA_TENANT_ID` | Tenant ID |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -43,6 +46,9 @@ _Please contribute by adding a CLI example._
 | `CONOHA_REGION` | The region |
 | `CONOHA_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_designate.md b/docs/content/dns/zz_gen_designate.md
index 090be577..fc14b92c 100644
--- a/docs/content/dns/zz_gen_designate.md
+++ b/docs/content/dns/zz_gen_designate.md
@@ -34,6 +34,9 @@ _Please contribute by adding a CLI example._
 | `OS_TENANT_NAME` | Tenant name |
 | `OS_USERNAME` | Username |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -43,6 +46,9 @@ _Please contribute by adding a CLI example._
 | `DESIGNATE_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `DESIGNATE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_digitalocean.md b/docs/content/dns/zz_gen_digitalocean.md
index 09b31f7a..6f28d49b 100644
--- a/docs/content/dns/zz_gen_digitalocean.md
+++ b/docs/content/dns/zz_gen_digitalocean.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `DO_AUTH_TOKEN` | Authentication token |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `DO_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `DO_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_dnsimple.md b/docs/content/dns/zz_gen_dnsimple.md
index 0689948b..7e3bb573 100644
--- a/docs/content/dns/zz_gen_dnsimple.md
+++ b/docs/content/dns/zz_gen_dnsimple.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `DNSIMPLE_BASE_URL` | API endpoint URL |
 | `DNSIMPLE_OAUTH_TOKEN` | OAuth token |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `DNSIMPLE_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `DNSIMPLE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_dnsmadeeasy.md b/docs/content/dns/zz_gen_dnsmadeeasy.md
index 5841f210..8aeede54 100644
--- a/docs/content/dns/zz_gen_dnsmadeeasy.md
+++ b/docs/content/dns/zz_gen_dnsmadeeasy.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `DNSMADEEASY_API_KEY` | The API key |
 | `DNSMADEEASY_API_SECRET` | The API Secret key |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -42,6 +45,9 @@ _Please contribute by adding a CLI example._
 | `DNSMADEEASY_SANDBOX` | Activate the sandbox (boolean) |
 | `DNSMADEEASY_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_dnspod.md b/docs/content/dns/zz_gen_dnspod.md
index 76b0f81c..545805d8 100644
--- a/docs/content/dns/zz_gen_dnspod.md
+++ b/docs/content/dns/zz_gen_dnspod.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `DNSPOD_API_KEY` | The user token |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `DNSPOD_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `DNSPOD_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_dreamhost.md b/docs/content/dns/zz_gen_dreamhost.md
index 01f90f5f..7929bb1c 100644
--- a/docs/content/dns/zz_gen_dreamhost.md
+++ b/docs/content/dns/zz_gen_dreamhost.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `DREAMHOST_API_KEY` | The API key |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `DREAMHOST_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `DREAMHOST_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_duckdns.md b/docs/content/dns/zz_gen_duckdns.md
index 3c891588..1b090bd5 100644
--- a/docs/content/dns/zz_gen_duckdns.md
+++ b/docs/content/dns/zz_gen_duckdns.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `DUCKDNS_TOKEN` | Account token |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `DUCKDNS_SEQUENCE_INTERVAL` | Interval between iteration |
 | `DUCKDNS_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_dyn.md b/docs/content/dns/zz_gen_dyn.md
index 10271700..ba339757 100644
--- a/docs/content/dns/zz_gen_dyn.md
+++ b/docs/content/dns/zz_gen_dyn.md
@@ -32,6 +32,9 @@ _Please contribute by adding a CLI example._
 | `DYN_PASSWORD` | Paswword |
 | `DYN_USER_NAME` | User name |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -42,6 +45,9 @@ _Please contribute by adding a CLI example._
 | `DYN_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `DYN_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_exoscale.md b/docs/content/dns/zz_gen_exoscale.md
index f764f3d4..66a83529 100644
--- a/docs/content/dns/zz_gen_exoscale.md
+++ b/docs/content/dns/zz_gen_exoscale.md
@@ -32,6 +32,9 @@ _Please contribute by adding a CLI example._
 | `EXOSCALE_API_SECRET` | API secret |
 | `EXOSCALE_ENDPOINT` | API endpoint URL |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -42,6 +45,9 @@ _Please contribute by adding a CLI example._
 | `EXOSCALE_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `EXOSCALE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_fastdns.md b/docs/content/dns/zz_gen_fastdns.md
index c46f23b6..7ac460f8 100644
--- a/docs/content/dns/zz_gen_fastdns.md
+++ b/docs/content/dns/zz_gen_fastdns.md
@@ -33,6 +33,9 @@ _Please contribute by adding a CLI example._
 | `AKAMAI_CLIENT_TOKEN` | Client token |
 | `AKAMAI_HOST` | API host |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -42,6 +45,9 @@ _Please contribute by adding a CLI example._
 | `AKAMAI_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `AKAMAI_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_gandi.md b/docs/content/dns/zz_gen_gandi.md
index feb2aa4d..b8f469bf 100644
--- a/docs/content/dns/zz_gen_gandi.md
+++ b/docs/content/dns/zz_gen_gandi.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `GANDI_API_KEY` | API key |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `GANDI_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `GANDI_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_gandiv5.md b/docs/content/dns/zz_gen_gandiv5.md
index b3b5ac1b..fb4f77ae 100644
--- a/docs/content/dns/zz_gen_gandiv5.md
+++ b/docs/content/dns/zz_gen_gandiv5.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `GANDIV5_API_KEY` | API key |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `GANDIV5_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `GANDIV5_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_gcloud.md b/docs/content/dns/zz_gen_gcloud.md
index de08207a..ea80e1d5 100644
--- a/docs/content/dns/zz_gen_gcloud.md
+++ b/docs/content/dns/zz_gen_gcloud.md
@@ -33,6 +33,9 @@ _Please contribute by adding a CLI example._
 | `GCE_SERVICE_ACCOUNT` | Account |
 | `GCE_SERVICE_ACCOUNT_FILE` | Account file path |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -42,6 +45,9 @@ _Please contribute by adding a CLI example._
 | `GCE_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `GCE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_glesys.md b/docs/content/dns/zz_gen_glesys.md
index 5413d90b..98684fee 100644
--- a/docs/content/dns/zz_gen_glesys.md
+++ b/docs/content/dns/zz_gen_glesys.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `GLESYS_API_KEY` | API key |
 | `GLESYS_API_USER` | API user |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `GLESYS_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `GLESYS_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_godaddy.md b/docs/content/dns/zz_gen_godaddy.md
index 1458ed15..d1829b8f 100644
--- a/docs/content/dns/zz_gen_godaddy.md
+++ b/docs/content/dns/zz_gen_godaddy.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `GODADDY_API_KEY` | **TODO** |
 | `GODADDY_API_SECRET` | **TODO** |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -42,6 +45,9 @@ _Please contribute by adding a CLI example._
 | `GODADDY_SEQUENCE_INTERVAL` | Interval between iteration |
 | `GODADDY_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_hostingde.md b/docs/content/dns/zz_gen_hostingde.md
index 5b927633..8155da38 100644
--- a/docs/content/dns/zz_gen_hostingde.md
+++ b/docs/content/dns/zz_gen_hostingde.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `HOSTINGDE_API_KEY` | **TODO** |
 | `HOSTINGDE_ZONE_NAME` | **TODO** |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `HOSTINGDE_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `HOSTINGDE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_httpreq.md b/docs/content/dns/zz_gen_httpreq.md
index 05c1cb63..c83c1a2d 100644
--- a/docs/content/dns/zz_gen_httpreq.md
+++ b/docs/content/dns/zz_gen_httpreq.md
@@ -34,6 +34,9 @@ lego --dns httpreq --domains my.domain.com --email my@email.com run
 | `HTTPREQ_ENDPOINT` | The URL of the server |
 | `HTTPREQ_MODE` | `RAW`, none |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -45,6 +48,9 @@ lego --dns httpreq --domains my.domain.com --email my@email.com run
 | `HTTPREQ_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `HTTPREQ_USERNAME` | **TODO** |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 ## Description
 
 The server must provide:
diff --git a/docs/content/dns/zz_gen_iij.md b/docs/content/dns/zz_gen_iij.md
index d1daea31..f1c58216 100644
--- a/docs/content/dns/zz_gen_iij.md
+++ b/docs/content/dns/zz_gen_iij.md
@@ -32,6 +32,9 @@ _Please contribute by adding a CLI example._
 | `IIJ_API_SECRET_KEY` | API secret key |
 | `IIJ_DO_SERVICE_CODE` | DO service code |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `IIJ_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `IIJ_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_inwx.md b/docs/content/dns/zz_gen_inwx.md
index 917a7e97..a55dc8a0 100644
--- a/docs/content/dns/zz_gen_inwx.md
+++ b/docs/content/dns/zz_gen_inwx.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `INWX_PASSWORD` | Password |
 | `INWX_USERNAME` | Username |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `INWX_SANDBOX` | Activate the sandbox (boolean) |
 | `INWX_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_lightsail.md b/docs/content/dns/zz_gen_lightsail.md
index 4e904bf4..c326e18b 100644
--- a/docs/content/dns/zz_gen_lightsail.md
+++ b/docs/content/dns/zz_gen_lightsail.md
@@ -32,6 +32,9 @@ _Please contribute by adding a CLI example._
 | `AWS_SECRET_ACCESS_KEY` | Secret access key |
 | `DNS_ZONE` | DNS zone |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `LIGHTSAIL_POLLING_INTERVAL` | Time between DNS propagation check |
 | `LIGHTSAIL_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_linode.md b/docs/content/dns/zz_gen_linode.md
index 6b6113b1..85e94aaa 100644
--- a/docs/content/dns/zz_gen_linode.md
+++ b/docs/content/dns/zz_gen_linode.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `LINODE_API_KEY` | API key |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -39,6 +42,9 @@ _Please contribute by adding a CLI example._
 | `LINODE_POLLING_INTERVAL` | Time between DNS propagation check |
 | `LINODE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_linodev4.md b/docs/content/dns/zz_gen_linodev4.md
index 317b701a..755bf829 100644
--- a/docs/content/dns/zz_gen_linodev4.md
+++ b/docs/content/dns/zz_gen_linodev4.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `LINODE_TOKEN` | API token |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -39,6 +42,9 @@ _Please contribute by adding a CLI example._
 | `LINODE_POLLING_INTERVAL` | Time between DNS propagation check |
 | `LINODE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_mydnsjp.md b/docs/content/dns/zz_gen_mydnsjp.md
index ac996c02..64a7cf21 100644
--- a/docs/content/dns/zz_gen_mydnsjp.md
+++ b/docs/content/dns/zz_gen_mydnsjp.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `MYDNSJP_MASTER_ID` | Master ID |
 | `MYDNSJP_PASSWORD` | Password |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `MYDNSJP_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `MYDNSJP_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_namecheap.md b/docs/content/dns/zz_gen_namecheap.md
index ba4197dd..5f69bd93 100644
--- a/docs/content/dns/zz_gen_namecheap.md
+++ b/docs/content/dns/zz_gen_namecheap.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `NAMECHEAP_API_KEY` | API key |
 | `NAMECHEAP_API_USER` | API user |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `NAMECHEAP_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `NAMECHEAP_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_namedotcom.md b/docs/content/dns/zz_gen_namedotcom.md
index 7f7ba304..7a1b3879 100644
--- a/docs/content/dns/zz_gen_namedotcom.md
+++ b/docs/content/dns/zz_gen_namedotcom.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `NAMECOM_API_TOKEN` | API token |
 | `NAMECOM_USERNAME` | Username |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `NAMECOM_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `NAMECOM_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_netcup.md b/docs/content/dns/zz_gen_netcup.md
index 4c42da06..5e6bf086 100644
--- a/docs/content/dns/zz_gen_netcup.md
+++ b/docs/content/dns/zz_gen_netcup.md
@@ -32,6 +32,9 @@ _Please contribute by adding a CLI example._
 | `NETCUP_API_PASSWORD` | API password |
 | `NETCUP_CUSTOMER_NUMBER` | Customer number |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -42,6 +45,9 @@ _Please contribute by adding a CLI example._
 | `NETCUP_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `NETCUP_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_nifcloud.md b/docs/content/dns/zz_gen_nifcloud.md
index 253b4f7a..7c86cd1a 100644
--- a/docs/content/dns/zz_gen_nifcloud.md
+++ b/docs/content/dns/zz_gen_nifcloud.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `NIFCLOUD_ACCESS_KEY_ID` | Access key |
 | `NIFCLOUD_SECRET_ACCESS_KEY` | Secret access key |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `NIFCLOUD_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `NIFCLOUD_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_ns1.md b/docs/content/dns/zz_gen_ns1.md
index 609b1e41..6ebf98b3 100644
--- a/docs/content/dns/zz_gen_ns1.md
+++ b/docs/content/dns/zz_gen_ns1.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `NS1_API_KEY` | API key |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `NS1_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `NS1_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_oraclecloud.md b/docs/content/dns/zz_gen_oraclecloud.md
index 42bad2ea..6ef84ba3 100644
--- a/docs/content/dns/zz_gen_oraclecloud.md
+++ b/docs/content/dns/zz_gen_oraclecloud.md
@@ -45,6 +45,9 @@ lego --dns oraclecloud --domains my.domain.com --email my@email.com run
 | `OCI_TENANCY_OCID` | Tenanct OCID |
 | `OCI_USER_OCID` | User OCID |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -54,6 +57,9 @@ lego --dns oraclecloud --domains my.domain.com --email my@email.com run
 | `OCI_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `OCI_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_otc.md b/docs/content/dns/zz_gen_otc.md
index 119bcfc5..684f0c95 100644
--- a/docs/content/dns/zz_gen_otc.md
+++ b/docs/content/dns/zz_gen_otc.md
@@ -34,6 +34,9 @@ _Please contribute by adding a CLI example._
 | `OTC_PROJECT_NAME` | Project name |
 | `OTC_USER_NAME` | User name |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -44,6 +47,9 @@ _Please contribute by adding a CLI example._
 | `OTC_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `OTC_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_ovh.md b/docs/content/dns/zz_gen_ovh.md
index 5b897df4..a75e05b4 100644
--- a/docs/content/dns/zz_gen_ovh.md
+++ b/docs/content/dns/zz_gen_ovh.md
@@ -33,6 +33,9 @@ _Please contribute by adding a CLI example._
 | `OVH_CONSUMER_KEY` | Consumer key |
 | `OVH_ENDPOINT` | Endpoint URL (ovh-eu or ovh-ca) |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -43,6 +46,9 @@ _Please contribute by adding a CLI example._
 | `OVH_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `OVH_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_pdns.md b/docs/content/dns/zz_gen_pdns.md
index f8834e9e..21f94352 100644
--- a/docs/content/dns/zz_gen_pdns.md
+++ b/docs/content/dns/zz_gen_pdns.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `PDNS_API_KEY` | API key |
 | `PDNS_API_URL` | API url |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `PDNS_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `PDNS_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 ## Information
 
 Tested and confirmed to work with PowerDNS authoritative server 3.4.8 and 4.0.1. Refer to [PowerDNS documentation](https://doc.powerdns.com/md/httpapi/README/) instructions on how to enable the built-in API interface.
diff --git a/docs/content/dns/zz_gen_rackspace.md b/docs/content/dns/zz_gen_rackspace.md
index 67113418..a0befc55 100644
--- a/docs/content/dns/zz_gen_rackspace.md
+++ b/docs/content/dns/zz_gen_rackspace.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `RACKSPACE_API_KEY` | API key |
 | `RACKSPACE_USER` | API user |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `RACKSPACE_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `RACKSPACE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_rfc2136.md b/docs/content/dns/zz_gen_rfc2136.md
index 22140092..c6c939df 100644
--- a/docs/content/dns/zz_gen_rfc2136.md
+++ b/docs/content/dns/zz_gen_rfc2136.md
@@ -33,6 +33,9 @@ _Please contribute by adding a CLI example._
 | `RFC2136_TSIG_KEY` | Name of the secret key as defined in DNS server configuration. To disable TSIG authentication, leave the `RFC2136_TSIG*` variables unset. |
 | `RFC2136_TSIG_SECRET` | Secret key payload. To disable TSIG authentication, leave the` RFC2136_TSIG*` variables unset. |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -44,6 +47,9 @@ _Please contribute by adding a CLI example._
 | `RFC2136_SEQUENCE_INTERVAL` | Interval between iteration |
 | `RFC2136_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_route53.md b/docs/content/dns/zz_gen_route53.md
index 48ae58b7..546531d4 100644
--- a/docs/content/dns/zz_gen_route53.md
+++ b/docs/content/dns/zz_gen_route53.md
@@ -33,6 +33,9 @@ _Please contribute by adding a CLI example._
 | `AWS_REGION` |  |
 | `AWS_SECRET_ACCESS_KEY` |  |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -42,6 +45,9 @@ _Please contribute by adding a CLI example._
 | `AWS_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `AWS_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 ## Description
 
 AWS Credentials are automatically detected in the following locations and prioritized in the following order:
diff --git a/docs/content/dns/zz_gen_sakuracloud.md b/docs/content/dns/zz_gen_sakuracloud.md
index 69b734d3..a29f666e 100644
--- a/docs/content/dns/zz_gen_sakuracloud.md
+++ b/docs/content/dns/zz_gen_sakuracloud.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `SAKURACLOUD_ACCESS_TOKEN` | Access token |
 | `SAKURACLOUD_ACCESS_TOKEN_SECRET` | Access token secret |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `SAKURACLOUD_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `SAKURACLOUD_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_selectel.md b/docs/content/dns/zz_gen_selectel.md
index ba452036..41c41d4b 100644
--- a/docs/content/dns/zz_gen_selectel.md
+++ b/docs/content/dns/zz_gen_selectel.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `SELECTEL_API_TOKEN` | API token |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `SELECTEL_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `SELECTEL_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_stackpath.md b/docs/content/dns/zz_gen_stackpath.md
index 04047729..274094fc 100644
--- a/docs/content/dns/zz_gen_stackpath.md
+++ b/docs/content/dns/zz_gen_stackpath.md
@@ -32,6 +32,9 @@ _Please contribute by adding a CLI example._
 | `STACKPATH_CLIENT_SECRET` | Client secret |
 | `STACKPATH_STACK_ID` | Stack ID |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `STACKPATH_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `STACKPATH_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_transip.md b/docs/content/dns/zz_gen_transip.md
index ad3457b1..61bbe4f3 100644
--- a/docs/content/dns/zz_gen_transip.md
+++ b/docs/content/dns/zz_gen_transip.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `TRANSIP_ACCOUNT_NAME` | Account name |
 | `TRANSIP_PRIVATE_KEY_PATH` | Private key path |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `TRANSIP_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `TRANSIP_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_vegadns.md b/docs/content/dns/zz_gen_vegadns.md
index 3958de8f..aa0c3f48 100644
--- a/docs/content/dns/zz_gen_vegadns.md
+++ b/docs/content/dns/zz_gen_vegadns.md
@@ -32,6 +32,9 @@ _Please contribute by adding a CLI example._
 | `SECRET_VEGADNS_SECRET` | API secret |
 | `VEGADNS_URL` | API endpoint URL |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `VEGADNS_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `VEGADNS_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_vscale.md b/docs/content/dns/zz_gen_vscale.md
index 76e09c94..07386b91 100644
--- a/docs/content/dns/zz_gen_vscale.md
+++ b/docs/content/dns/zz_gen_vscale.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `VSCALE_API_TOKEN` | API token |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -41,6 +44,9 @@ _Please contribute by adding a CLI example._
 | `VSCALE_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `VSCALE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_vultr.md b/docs/content/dns/zz_gen_vultr.md
index 8d7ad724..d514d52f 100644
--- a/docs/content/dns/zz_gen_vultr.md
+++ b/docs/content/dns/zz_gen_vultr.md
@@ -30,6 +30,9 @@ _Please contribute by adding a CLI example._
 |-----------------------|-------------|
 | `VULTR_API_KEY` | API key |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -40,6 +43,9 @@ _Please contribute by adding a CLI example._
 | `VULTR_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `VULTR_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/dns/zz_gen_zoneee.md b/docs/content/dns/zz_gen_zoneee.md
index a04398fc..9a7fb6bb 100644
--- a/docs/content/dns/zz_gen_zoneee.md
+++ b/docs/content/dns/zz_gen_zoneee.md
@@ -31,6 +31,9 @@ _Please contribute by adding a CLI example._
 | `ZONEEE_API_KEY` | API key |
 | `ZONEEE_API_USER` | API user |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 ## Additional Configuration
 
@@ -42,6 +45,9 @@ _Please contribute by adding a CLI example._
 | `ZONEEE_PROPAGATION_TIMEOUT` | Maximum waiting time for DNS propagation |
 | `ZONEEE_TTL` | The TTL of the TXT record used for the DNS challenge |
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
+
 
 
 
diff --git a/docs/content/usage/cli/_index.md b/docs/content/usage/cli/_index.md
index 3b3c0e83..11174d6a 100644
--- a/docs/content/usage/cli/_index.md
+++ b/docs/content/usage/cli/_index.md
@@ -22,7 +22,7 @@ COMMANDS:
      run      Register an account, then create and install a certificate
      revoke   Revoke a certificate
      renew    Renew a certificate
-     dnshelp  Shows additional help for the --dns global option
+     dnshelp  Shows additional help for the '--dns' global option
      list     Display certificates and accounts information.
      help, h  Shows a list of commands or help for one command
 
@@ -35,7 +35,7 @@ GLOBAL OPTIONS:
    --eab                        Use External Account Binding for account registration. Requires --kid and --hmac.
    --kid value                  Key identifier from External CA. Used for External Account Binding.
    --hmac value                 MAC key from External CA. Should be in Base64 URL Encoding without padding format. Used for External Account Binding.
-   --key-type value, -k value   Key type to use for private keys. Supported: rsa2048, rsa4096, rsa8192, ec256, ec384. (default: "rsa2048")
+   --key-type value, -k value   Key type to use for private keys. Supported: rsa2048, rsa4096, rsa8192, ec256, ec384. (default: "ec384")
    --filename value             (deprecated) Filename of the generated certificate.
    --path value                 Directory to use for storing the data. (default: "./.lego")
    --http                       Use the HTTP challenge to solve challenges. Can be mixed with other types of challenges.
diff --git a/internal/dnsdocs/dns.md.tmpl b/internal/dnsdocs/dns.md.tmpl
index 4f01412c..af860770 100644
--- a/internal/dnsdocs/dns.md.tmpl
+++ b/internal/dnsdocs/dns.md.tmpl
@@ -40,6 +40,8 @@ _Please contribute by adding a CLI example._
 | `{{$k}}` | {{$v}} |
 {{- end}}
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
 {{- end}}
 
 {{if .Configuration.Additional }}
@@ -51,6 +53,8 @@ _Please contribute by adding a CLI example._
 | `{{$k}}` | {{$v}} |
 {{- end}}
 
+The environment variable names can be suffixed by `_FILE` to reference a file instead of a value.
+More information [here](/lego/dns/#configuration-and-credentials).
 {{- end}}
 {{- end}}