traefik/docs/content/https/acme.md

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# Let's Encrypt
Automatic HTTPS
{: .subtitle }
You can configure Traefik to use an ACME provider (like Let's Encrypt) for automatic certificate generation.
!!! warning "Let's Encrypt and Rate Limiting"
Note that Let's Encrypt API has [rate limiting](https://letsencrypt.org/docs/rate-limits).
## Configuration Examples
??? example "Enabling ACME"
```toml tab="File (TOML)"
[entryPoints]
[entryPoints.web]
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address = ":80"
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[entryPoints.web-secure]
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address = ":443"
[certificatesResolvers.sample.acme]
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email = "your-email@your-domain.org"
storage = "acme.json"
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[certificatesResolvers.sample.acme.httpChallenge]
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# used during the challenge
entryPoint = "web"
```
```yaml tab="File (YAML)"
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entryPoints:
web:
address: ":80"
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web-secure:
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address: ":443"
certificatesResolvers:
sample:
acme:
email: your-email@your-domain.org
storage: acme.json
httpChallenge:
# used during the challenge
entryPoint: web
```
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```bash tab="CLI"
--entryPoints.web.address=":80"
--entryPoints.websecure.address=":443"
# ...
--certificatesResolvers.sample.acme.email="your-email@your-domain.org"
--certificatesResolvers.sample.acme.storage="acme.json"
# used during the challenge
--certificatesResolvers.sample.acme.httpChallenge.entryPoint=web
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```
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!!! important "Defining a certificates resolver does not result in all routers automatically using it. Each router that is supposed to use the resolver must [reference](../routing/routers/index.md#certresolver) it."
??? note "Configuration Reference"
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There are many available options for ACME.
For a quick glance at what's possible, browse the configuration reference:
```toml tab="File (TOML)"
--8<-- "content/https/ref-acme.toml"
```
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```yaml tab="File (YAML)"
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--8<-- "content/https/ref-acme.yaml"
```
```bash tab="CLI"
--8<-- "content/https/ref-acme.txt"
```
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## Automatic Renewals
Traefik automatically tracks the expiry date of ACME certificates it generates.
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If there are less than 30 days remaining before the certificate expires, Traefik will attempt to renew it automatically.
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!!! info ""
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Certificates that are no longer used may still be renewed, as Traefik does not currently check if the certificate is being used before renewing.
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## The Different ACME Challenges
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!!! important "Defining a certificates resolver does not result in all routers automatically using it. Each router that is supposed to use the resolver must [reference](../routing/routers/index.md#certresolver) it."
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### `tlsChallenge`
Use the `TLS-ALPN-01` challenge to generate and renew ACME certificates by provisioning a TLS certificate.
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As described on the Let's Encrypt [community forum](https://community.letsencrypt.org/t/support-for-ports-other-than-80-and-443/3419/72),
when using the `TLS-ALPN-01` challenge, Traefik must be reachable by Let's Encrypt through port 443.
??? example "Configuring the `tlsChallenge`"
```toml tab="File (TOML)"
[certificatesResolvers.sample.acme]
# ...
[certificatesResolvers.sample.acme.tlsChallenge]
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```
```yaml tab="File (YAML)"
certificatesResolvers:
sample:
acme:
# ...
tlsChallenge: {}
```
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```bash tab="CLI"
# ...
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--certificatesResolvers.sample.acme.tlsChallenge=true
```
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### `httpChallenge`
Use the `HTTP-01` challenge to generate and renew ACME certificates by provisioning an HTTP resource under a well-known URI.
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As described on the Let's Encrypt [community forum](https://community.letsencrypt.org/t/support-for-ports-other-than-80-and-443/3419/72),
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when using the `HTTP-01` challenge, `certificatesResolvers.sample.acme.httpChallenge.entryPoint` must be reachable by Let's Encrypt through port 80.
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??? example "Using an EntryPoint Called http for the `httpChallenge`"
```toml tab="File (TOML)"
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[entryPoints]
[entryPoints.web]
address = ":80"
[entryPoints.web-secure]
address = ":443"
[certificatesResolvers.sample.acme]
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# ...
[certificatesResolvers.sample.acme.httpChallenge]
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entryPoint = "web"
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```
```yaml tab="File (YAML)"
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entryPoints:
web:
address: ":80"
web-secure:
address: ":443"
certificatesResolvers:
sample:
acme:
# ...
httpChallenge:
entryPoint: web
```
```bash tab="CLI"
--entryPoints.web.address=":80"
--entryPoints.websecure.address=":443"
# ...
--certificatesResolvers.sample.acme.httpChallenge.entryPoint=web
```
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!!! info ""
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Redirection is fully compatible with the `HTTP-01` challenge.
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### `dnsChallenge`
Use the `DNS-01` challenge to generate and renew ACME certificates by provisioning a DNS record.
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??? example "Configuring a `dnsChallenge` with the DigitalOcean Provider"
```toml tab="File (TOML)"
[certificatesResolvers.sample.acme]
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# ...
[certificatesResolvers.sample.acme.dnsChallenge]
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provider = "digitalocean"
delayBeforeCheck = 0
# ...
```
```yaml tab="File (YAML)"
certificatesResolvers:
sample:
acme:
# ...
dnsChallenge:
provider: digitalocean
delayBeforeCheck: 0
# ...
```
```bash tab="CLI"
# ...
--certificatesResolvers.sample.acme.dnsChallenge.provider=digitalocean
--certificatesResolvers.sample.acme.dnsChallenge.delayBeforeCheck=0
# ...
```
!!! important
A `provider` is mandatory.
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#### `providers`
Here is a list of supported `providers`, that can automate the DNS verification,
along with the required environment variables and their [wildcard & root domain support](#wildcard-domains).
Do not hesitate to complete it.
Every lego environment variable can be overridden by their respective `_FILE` counterpart, which should have a filepath to a file that contains the secret as its value.
For example, `CF_API_EMAIL_FILE=/run/secrets/traefik_cf-api-email` could be used to provide a Cloudflare API email address as a Docker secret named `traefik_cf-api-email`.
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| Provider Name | Provider Code | Environment Variables | |
|-------------------------------------------------------------|----------------|---------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------|
| [ACME DNS](https://github.com/joohoi/acme-dns) | `acme-dns` | `ACME_DNS_API_BASE`, `ACME_DNS_STORAGE_PATH` | [Additional configuration](https://go-acme.github.io/lego/dns/acme-dns) |
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| [Alibaba Cloud](https://www.alibabacloud.com) | `alidns` | `ALICLOUD_ACCESS_KEY`, `ALICLOUD_SECRET_KEY`, `ALICLOUD_REGION_ID` | [Additional configuration](https://go-acme.github.io/lego/dns/alidns) |
| [Auroradns](https://www.pcextreme.com/aurora/dns) | `auroradns` | `AURORA_USER_ID`, `AURORA_KEY`, `AURORA_ENDPOINT` | [Additional configuration](https://go-acme.github.io/lego/dns/auroradns) |
| [Azure](https://azure.microsoft.com/services/dns/) | `azure` | `AZURE_CLIENT_ID`, `AZURE_CLIENT_SECRET`, `AZURE_SUBSCRIPTION_ID`, `AZURE_TENANT_ID`, `AZURE_RESOURCE_GROUP`, `[AZURE_METADATA_ENDPOINT]` | [Additional configuration](https://go-acme.github.io/lego/dns/azure) |
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| [Bindman](https://github.com/labbsr0x/bindman-dns-webhook) | `bindman` | `BINDMAN_MANAGER_ADDRESS` | [Additional configuration](https://go-acme.github.io/lego/dns/bindman) |
| [Blue Cat](https://www.bluecatnetworks.com/) | `bluecat` | `BLUECAT_SERVER_URL`, `BLUECAT_USER_NAME`, `BLUECAT_PASSWORD`, `BLUECAT_CONFIG_NAME`, `BLUECAT_DNS_VIEW` | [Additional configuration](https://go-acme.github.io/lego/dns/bluecat) |
| [ClouDNS](https://www.cloudns.net/) | `cloudns` | `CLOUDNS_AUTH_ID`, `CLOUDNS_AUTH_PASSWORD` | [Additional configuration](https://go-acme.github.io/lego/dns/cloudns) |
| [Cloudflare](https://www.cloudflare.com) | `cloudflare` | `CF_API_EMAIL`, `CF_API_KEY` - The `Global API Key` needs to be used, not the `Origin CA Key` | [Additional configuration](https://go-acme.github.io/lego/dns/cloudflare) |
| [CloudXNS](https://www.cloudxns.net) | `cloudxns` | `CLOUDXNS_API_KEY`, `CLOUDXNS_SECRET_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/cloudxns) |
| [ConoHa](https://www.conoha.jp) | `conoha` | `CONOHA_TENANT_ID`, `CONOHA_API_USERNAME`, `CONOHA_API_PASSWORD` | [Additional configuration](https://go-acme.github.io/lego/dns/conoha) |
| [DigitalOcean](https://www.digitalocean.com) | `digitalocean` | `DO_AUTH_TOKEN` | [Additional configuration](https://go-acme.github.io/lego/dns/digitalocean) |
| [DNSimple](https://dnsimple.com) | `dnsimple` | `DNSIMPLE_OAUTH_TOKEN`, `DNSIMPLE_BASE_URL` | [Additional configuration](https://go-acme.github.io/lego/dns/dnsimple) |
| [DNS Made Easy](https://dnsmadeeasy.com) | `dnsmadeeasy` | `DNSMADEEASY_API_KEY`, `DNSMADEEASY_API_SECRET`, `DNSMADEEASY_SANDBOX` | [Additional configuration](https://go-acme.github.io/lego/dns/dnsmadeeasy) |
| [DNSPod](https://www.dnspod.com/) | `dnspod` | `DNSPOD_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/dnspod) |
| [Domain Offensive (do.de)](https://www.do.de/) | `dode` | `DODE_TOKEN` | [Additional configuration](https://go-acme.github.io/lego/dns/dode) |
| [DreamHost](https://www.dreamhost.com/) | `dreamhost` | `DREAMHOST_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/dreamhost) |
| [Duck DNS](https://www.duckdns.org/) | `duckdns` | `DUCKDNS_TOKEN` | [Additional configuration](https://go-acme.github.io/lego/dns/duckdns) |
| [Dyn](https://dyn.com) | `dyn` | `DYN_CUSTOMER_NAME`, `DYN_USER_NAME`, `DYN_PASSWORD` | [Additional configuration](https://go-acme.github.io/lego/dns/dyn) |
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| [EasyDNS](https://easydns.com/) | `easydns` | `EASYDNS_TOKEN`, `EASYDNS_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/easydns) |
| External Program | `exec` | `EXEC_PATH` | [Additional configuration](https://go-acme.github.io/lego/dns/exec) |
| [Exoscale](https://www.exoscale.com) | `exoscale` | `EXOSCALE_API_KEY`, `EXOSCALE_API_SECRET`, `EXOSCALE_ENDPOINT` | [Additional configuration](https://go-acme.github.io/lego/dns/exoscale) |
| [Fast DNS](https://www.akamai.com/) | `fastdns` | `AKAMAI_CLIENT_TOKEN`, `AKAMAI_CLIENT_SECRET`, `AKAMAI_ACCESS_TOKEN` | [Additional configuration](https://go-acme.github.io/lego/dns/fastdns) |
| [Gandi](https://www.gandi.net) | `gandi` | `GANDI_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/gandi) |
| [Gandi v5](http://doc.livedns.gandi.net) | `gandiv5` | `GANDIV5_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/gandiv5) |
| [Glesys](https://glesys.com/) | `glesys` | `GLESYS_API_USER`, `GLESYS_API_KEY`, `GLESYS_DOMAIN` | [Additional configuration](https://go-acme.github.io/lego/dns/glesys) |
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| [GoDaddy](https://godaddy.com/) | `godaddy` | `GODADDY_API_KEY`, `GODADDY_API_SECRET` | [Additional configuration](https://go-acme.github.io/lego/dns/godaddy) |
| [Google Cloud DNS](https://cloud.google.com/dns/docs/) | `gcloud` | `GCE_PROJECT`, Application Default Credentials [^2] [^3], [`GCE_SERVICE_ACCOUNT_FILE`] | [Additional configuration](https://go-acme.github.io/lego/dns/gcloud) |
| [hosting.de](https://www.hosting.de) | `hostingde` | `HOSTINGDE_API_KEY`, `HOSTINGDE_ZONE_NAME` | [Additional configuration](https://go-acme.github.io/lego/dns/hostingde) |
| HTTP request | `httpreq` | `HTTPREQ_ENDPOINT`, `HTTPREQ_MODE`, `HTTPREQ_USERNAME`, `HTTPREQ_PASSWORD` [^1] | [Additional configuration](https://go-acme.github.io/lego/dns/httpreq) |
| [IIJ](https://www.iij.ad.jp/) | `iij` | `IIJ_API_ACCESS_KEY`, `IIJ_API_SECRET_KEY`, `IIJ_DO_SERVICE_CODE` | [Additional configuration](https://go-acme.github.io/lego/dns/iij) |
| [INWX](https://www.inwx.de/en) | `inwx` | `INWX_USERNAME`, `INWX_PASSWORD` | [Additional configuration](https://go-acme.github.io/lego/dns/inwx) |
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| [Joker.com](https://joker.com) | `joker` | `JOKER_API_KEY` or `JOKER_USERNAME`, `JOKER_PASSWORD` | [Additional configuration](https://go-acme.github.io/lego/dns/joker) |
| [Lightsail](https://aws.amazon.com/lightsail/) | `lightsail` | `AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY`, `DNS_ZONE` | [Additional configuration](https://go-acme.github.io/lego/dns/lightsail) |
| [Linode](https://www.linode.com) | `linode` | `LINODE_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/linode) |
| [Linode v4](https://www.linode.com) | `linodev4` | `LINODE_TOKEN` | [Additional configuration](https://go-acme.github.io/lego/dns/linodev4) |
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| manual | - | none, but you need to run Traefik interactively [^4], turn on debug log to see instructions and press <kbd>Enter</kbd>. | |
| [MyDNS.jp](https://www.mydns.jp/) | `mydnsjp` | `MYDNSJP_MASTER_ID`, `MYDNSJP_PASSWORD` | [Additional configuration](https://go-acme.github.io/lego/dns/mydnsjp) |
| [Namecheap](https://www.namecheap.com) | `namecheap` | `NAMECHEAP_API_USER`, `NAMECHEAP_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/namecheap) |
| [name.com](https://www.name.com/) | `namedotcom` | `NAMECOM_USERNAME`, `NAMECOM_API_TOKEN`, `NAMECOM_SERVER` | [Additional configuration](https://go-acme.github.io/lego/dns/namedotcom) |
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| [Namesilo](https://www.namesilo.com/) | `namesilo` | `NAMESILO_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/namesilo) |
| [Netcup](https://www.netcup.eu/) | `netcup` | `NETCUP_CUSTOMER_NUMBER`, `NETCUP_API_KEY`, `NETCUP_API_PASSWORD` | [Additional configuration](https://go-acme.github.io/lego/dns/netcup) |
| [NIFCloud](https://cloud.nifty.com/service/dns.htm) | `nifcloud` | `NIFCLOUD_ACCESS_KEY_ID`, `NIFCLOUD_SECRET_ACCESS_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/nifcloud) |
| [Ns1](https://ns1.com/) | `ns1` | `NS1_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/ns1) |
| [Open Telekom Cloud](https://cloud.telekom.de) | `otc` | `OTC_DOMAIN_NAME`, `OTC_USER_NAME`, `OTC_PASSWORD`, `OTC_PROJECT_NAME`, `OTC_IDENTITY_ENDPOINT` | [Additional configuration](https://go-acme.github.io/lego/dns/otc) |
| [OVH](https://www.ovh.com) | `ovh` | `OVH_ENDPOINT`, `OVH_APPLICATION_KEY`, `OVH_APPLICATION_SECRET`, `OVH_CONSUMER_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/ovh) |
| [Openstack Designate](https://docs.openstack.org/designate) | `designate` | `OS_AUTH_URL`, `OS_USERNAME`, `OS_PASSWORD`, `OS_TENANT_NAME`, `OS_REGION_NAME` | [Additional configuration](https://go-acme.github.io/lego/dns/designate) |
| [Oracle Cloud](https://cloud.oracle.com/home) | `oraclecloud` | `OCI_COMPARTMENT_OCID`, `OCI_PRIVKEY_FILE`, `OCI_PRIVKEY_PASS`, `OCI_PUBKEY_FINGERPRINT`, `OCI_REGION`, `OCI_TENANCY_OCID`, `OCI_USER_OCID` | [Additional configuration](https://go-acme.github.io/lego/dns/oraclecloud) |
| [PowerDNS](https://www.powerdns.com) | `pdns` | `PDNS_API_KEY`, `PDNS_API_URL` | [Additional configuration](https://go-acme.github.io/lego/dns/pdns) |
| [Rackspace](https://www.rackspace.com/cloud/dns) | `rackspace` | `RACKSPACE_USER`, `RACKSPACE_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/rackspace) |
| [RFC2136](https://tools.ietf.org/html/rfc2136) | `rfc2136` | `RFC2136_TSIG_KEY`, `RFC2136_TSIG_SECRET`, `RFC2136_TSIG_ALGORITHM`, `RFC2136_NAMESERVER` | [Additional configuration](https://go-acme.github.io/lego/dns/rfc2136) |
| [Route 53](https://aws.amazon.com/route53/) | `route53` | `AWS_ACCESS_KEY_ID`, `AWS_SECRET_ACCESS_KEY`, `[AWS_REGION]`, `[AWS_HOSTED_ZONE_ID]` or a configured user/instance IAM profile. | [Additional configuration](https://go-acme.github.io/lego/dns/route53) |
| [Sakura Cloud](https://cloud.sakura.ad.jp/) | `sakuracloud` | `SAKURACLOUD_ACCESS_TOKEN`, `SAKURACLOUD_ACCESS_TOKEN_SECRET` | [Additional configuration](https://go-acme.github.io/lego/dns/sakuracloud) |
| [Selectel](https://selectel.ru/en/) | `selectel` | `SELECTEL_API_TOKEN` | [Additional configuration](https://go-acme.github.io/lego/dns/selectel) |
| [Stackpath](https://www.stackpath.com/) | `stackpath` | `STACKPATH_CLIENT_ID`, `STACKPATH_CLIENT_SECRET`, `STACKPATH_STACK_ID` | [Additional configuration](https://go-acme.github.io/lego/dns/stackpath) |
| [TransIP](https://www.transip.nl/) | `transip` | `TRANSIP_ACCOUNT_NAME`, `TRANSIP_PRIVATE_KEY_PATH` | [Additional configuration](https://go-acme.github.io/lego/dns/transip) |
| [VegaDNS](https://github.com/shupp/VegaDNS-API) | `vegadns` | `SECRET_VEGADNS_KEY`, `SECRET_VEGADNS_SECRET`, `VEGADNS_URL` | [Additional configuration](https://go-acme.github.io/lego/dns/vegadns) |
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| [Versio](https://www.versio.nl/domeinnamen) | `versio` | `VERSIO_USERNAME`, `VERSIO_PASSWORD` | [Additional configuration](https://go-acme.github.io/lego/dns/versio) |
| [Vscale](https://vscale.io/) | `vscale` | `VSCALE_API_TOKEN` | [Additional configuration](https://go-acme.github.io/lego/dns/vscale) |
| [VULTR](https://www.vultr.com) | `vultr` | `VULTR_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/vultr) |
| [Zone.ee](https://www.zone.ee) | `zoneee` | `ZONEEE_API_USER`, `ZONEEE_API_KEY` | [Additional configuration](https://go-acme.github.io/lego/dns/zoneee) |
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[^1]: more information about the HTTP message format can be found [here](https://go-acme.github.io/lego/dns/httpreq/)
[^2]: [providing_credentials_to_your_application](https://cloud.google.com/docs/authentication/production#providing_credentials_to_your_application)
[^3]: [google/default.go](https://github.com/golang/oauth2/blob/36a7019397c4c86cf59eeab3bc0d188bac444277/google/default.go#L61-L76)
[^4]: `docker stack` remark: there is no way to support terminal attached to container when deploying with `docker stack`, so you might need to run container with `docker run -it` to generate certificates using `manual` provider.
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!!! info "`delayBeforeCheck`"
By default, the `provider` verifies the TXT record _before_ letting ACME verify.
You can delay this operation by specifying a delay (in seconds) with `delayBeforeCheck` (value must be greater than zero).
This option is useful when internal networks block external DNS queries.
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#### `resolvers`
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Use custom DNS servers to resolve the FQDN authority.
```toml tab="File (TOML)"
[certificatesResolvers.sample.acme]
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# ...
[certificatesResolvers.sample.acme.dnsChallenge]
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# ...
resolvers = ["1.1.1.1:53", "8.8.8.8:53"]
```
```yaml tab="File (YAML)"
certificatesResolvers:
sample:
acme:
# ...
dnsChallenge:
# ...
resolvers:
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- "1.1.1.1:53"
- "8.8.8.8:53"
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```
```bash tab="CLI"
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# ...
--certificatesResolvers.sample.acme.dnsChallenge.resolvers:="1.1.1.1:53,8.8.8.8:53"
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```
#### Wildcard Domains
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[ACME V2](https://community.letsencrypt.org/t/acme-v2-and-wildcard-certificate-support-is-live/55579) supports wildcard certificates.
As described in [Let's Encrypt's post](https://community.letsencrypt.org/t/staging-endpoint-for-acme-v2/49605) wildcard certificates can only be generated through a [`DNS-01` challenge](#dnschallenge).
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## `caServer`
??? example "Using the Let's Encrypt staging server"
```toml tab="File (TOML)"
[certificatesResolvers.sample.acme]
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# ...
caServer = "https://acme-staging-v02.api.letsencrypt.org/directory"
# ...
```
```yaml tab="File (YAML)"
certificatesResolvers:
sample:
acme:
# ...
caServer: https://acme-staging-v02.api.letsencrypt.org/directory
# ...
```
```bash tab="CLI"
# ...
--certificatesResolvers.sample.acme.caServer="https://acme-staging-v02.api.letsencrypt.org/directory"
# ...
```
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## `storage`
The `storage` option sets the location where your ACME certificates are saved to.
```toml tab="File (TOML)"
[certificatesResolvers.sample.acme]
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# ...
storage = "acme.json"
# ...
```
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```yaml tab="File (YAML)"
certificatesResolvers:
sample:
acme:
# ...
storage: acme.json
# ...
```
```bash tab="CLI"
# ...
--certificatesResolvers.sample.acme.storage=acme.json
# ...
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```
The value can refer to some kinds of storage:
- a JSON file
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### In a File
ACME certificates can be stored in a JSON file that needs to have a `600` file mode .
In Docker you can mount either the JSON file, or the folder containing it:
```bash
docker run -v "/my/host/acme.json:acme.json" traefik
```
```bash
docker run -v "/my/host/acme:/etc/traefik/acme" traefik
```
!!! warning
For concurrency reason, this file cannot be shared across multiple instances of Traefik. Use a key value store entry instead.
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## Fallback
If Let's Encrypt is not reachable, the following certificates will apply:
1. Previously generated ACME certificates (before downtime)
1. Expired ACME certificates
1. Provided certificates
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!!! important
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For new (sub)domains which need Let's Encrypt authentication, the default Traefik certificate will be used until Traefik is restarted.