User Guide¶
Table of Contents
Certbot Commands¶
Certbot uses a number of different commands (also referred to as “subcommands”) to request specific actions such as obtaining, renewing, or revoking certificates. The most important and commonly-used commands will be discussed throughout this document; an exhaustive list also appears near the end of the document.
The certbot
script on your web server might be named letsencrypt
if your system uses an older package, or certbot-auto
if you used an alternate installation method. Throughout the docs, whenever you see certbot
, swap in the correct name as needed.
Getting certificates (and choosing plugins)¶
The Certbot client supports two types of plugins for obtaining and installing certificates: authenticators and installers.
Authenticators are plugins used with the certonly
command to obtain a cert.
The authenticator validates that you
control the domain(s) you are requesting a cert for, obtains a cert for the specified
domain(s), and places the cert in the /etc/letsencrypt
directory on your
machine. The authenticator does not install the cert (it does not edit any of your server’s configuration files to serve the
obtained certificate). If you specify multiple domains to authenticate, they will
all be listed in a single certificate. To obtain multiple separate certificates
you will need to run Certbot multiple times.
Installers are Plugins used with the install
command to install a cert.
These plugins can modify your webserver’s configuration to
serve your website over HTTPS using certificates obtained by certbot.
Plugins that do both can be used with the certbot run
command, which is the default
when no command is specified. The run
subcommand can also be used to specify
a combination of distinct authenticator and installer plugins.
Plugin | Auth | Inst | Notes | Challenge types (and port) |
---|---|---|---|---|
apache | Y | Y | Automates obtaining and installing a cert with Apache 2.4 on
Debian-based distributions with
libaugeas0 1.0+. |
tls-sni-01 (443) |
webroot | Y | N | Obtains a cert by writing to the webroot directory of an
already running webserver.
|
http-01 (80) |
nginx | Y | Y | Automates obtaining and installing a cert with Nginx. Alpha
release shipped with Certbot 0.9.0.
|
tls-sni-01 (443) |
standalone | Y | N | Uses a “standalone” webserver to obtain a cert. Requires
port 80 or 443 to be available. This is useful on systems
with no webserver, or when direct integration with the local
webserver is not supported or not desired.
|
http-01 (80) or tls-sni-01 (443) |
manual | Y | N | Helps you obtain a cert by giving you instructions to perform
domain validation yourself. Additionally allows you to
specify scripts to automate the validation task in a
customized way.
|
http-01 (80) or dns-01 (53) |
Under the hood, plugins use one of several ACME protocol challenges to
prove you control a domain. The options are http-01 (which uses port 80),
tls-sni-01 (port 443) and dns-01 (requiring configuration of a DNS server on
port 53, though that’s often not the same machine as your webserver). A few
plugins support more than one challenge type, in which case you can choose one
with --preferred-challenges
.
There are also many third-party-plugins available. Below we describe in more detail the circumstances in which each plugin can be used, and how to use it.
Apache¶
The Apache plugin currently requires an OS with augeas version 1.0; currently it
supports
modern OSes based on Debian, Fedora, SUSE, Gentoo and Darwin.
This automates both obtaining and installing certs on an Apache
webserver. To specify this plugin on the command line, simply include
--apache
.
Webroot¶
If you’re running a local webserver for which you have the ability
to modify the content being served, and you’d prefer not to stop the
webserver during the certificate issuance process, you can use the webroot
plugin to obtain a cert by including certonly
and --webroot
on
the command line. In addition, you’ll need to specify --webroot-path
or -w
with the top-level directory (“web root”) containing the files
served by your webserver. For example, --webroot-path /var/www/html
or --webroot-path /usr/share/nginx/html
are two common webroot paths.
If you’re getting a certificate for many domains at once, the plugin
needs to know where each domain’s files are served from, which could
potentially be a separate directory for each domain. When requesting a
certificate for multiple domains, each domain will use the most recently
specified --webroot-path
. So, for instance,
certbot certonly --webroot -w /var/www/example/ -d www.example.com -d example.com -w /var/www/other -d other.example.net -d another.other.example.net
would obtain a single certificate for all of those names, using the
/var/www/example
webroot directory for the first two, and
/var/www/other
for the second two.
The webroot plugin works by creating a temporary file for each of your requested
domains in ${webroot-path}/.well-known/acme-challenge
. Then the Let’s Encrypt
validation server makes HTTP requests to validate that the DNS for each
requested domain resolves to the server running certbot. An example request
made to your web server would look like:
66.133.109.36 - - [05/Jan/2016:20:11:24 -0500] "GET /.well-known/acme-challenge/HGr8U1IeTW4kY_Z6UIyaakzOkyQgPr_7ArlLgtZE8SX HTTP/1.1" 200 87 "-" "Mozilla/5.0 (compatible; Let's Encrypt validation server; +https://www.letsencrypt.org)"
Note that to use the webroot plugin, your server must be configured to serve
files from hidden directories. If /.well-known
is treated specially by
your webserver configuration, you might need to modify the configuration
to ensure that files inside /.well-known/acme-challenge
are served by
the webserver.
Nginx¶
The Nginx plugin has been distributed with Certbot since version 0.9.0 and should
work for most configurations. Because it is alpha code, we recommend backing up Nginx
configurations before using it (though you can also revert changes to
configurations with certbot --nginx rollback
). You can use it by providing
the --nginx
flag on the commandline.
certbot --nginx
Standalone¶
Use standalone mode to obtain a cert if you don’t want to use (or don’t currently have) existing server software. The standalone plugin does not rely on any other server software running on the machine where you obtain the cert.
To obtain a cert using a “standalone” webserver, you can use the
standalone plugin by including certonly
and --standalone
on the command line. This plugin needs to bind to port 80 or 443 in
order to perform domain validation, so you may need to stop your
existing webserver. To control which port the plugin uses, include
one of the options shown below on the command line.
--preferred-challenges http
to use port 80--preferred-challenges tls-sni
to use port 443
It must still be possible for your machine to accept inbound connections from the Internet on the specified port using each requested domain name.
Note
The --standalone-supported-challenges
option has been
deprecated since certbot
version 0.9.0.
Manual¶
If you’d like to obtain a cert running certbot
on a machine
other than your target webserver or perform the steps for domain
validation yourself, you can use the manual plugin. While hidden from
the UI, you can use the plugin to obtain a cert by specifying
certonly
and --manual
on the command line. This requires you
to copy and paste commands into another terminal session, which may
be on a different computer.
The manual plugin can use either the http
or the dns
challenge. You
can use the --preferred-challenges
option to choose the challenge of your
preference.
The http
challenge will ask you to place a file with a specific name and
specific content in the /.well-known/acme-challenge/
directory directly
in the top-level directory (“web root”) containing the files served by your
webserver. In essence it’s the same as the webroot plugin, but not automated.
When using the dns
plugin, certbot
will ask you to place a TXT DNS
record with specific contents under the domain name consisting of the hostname
for which you want a certificate issued, prepended by _acme-challenge
.
For example, for the domain example.com
, a zone file entry would look like:
_acme-challenge.example.com. 300 IN TXT "gfj9Xq...Rg85nM"
Additionally you can specify scripts to prepare for validation and perform the
authentication procedure and/or clean up after it by using the
--manual-auth-hook
and --manual-cleanup-hook
flags. This is described in
more depth in the hooks section.
Third-party plugins¶
There are also a number of third-party plugins for the client, provided by other developers. Many are beta/experimental, but some are already in widespread use:
Plugin | Auth | Inst | Notes |
---|---|---|---|
plesk | Y | Y | Integration with the Plesk web hosting tool |
haproxy | Y | Y | Integration with the HAProxy load balancer |
s3front | Y | Y | Integration with Amazon CloudFront distribution of S3 buckets |
gandi | Y | Y | Integration with Gandi’s hosting products and API |
varnish | Y | N | Obtain certs via a Varnish server |
external | Y | N | A plugin for convenient scripting (See also ticket 2782) |
icecast | N | Y | Deploy certs to Icecast 2 streaming media servers |
pritunl | N | Y | Install certs in pritunl distributed OpenVPN servers |
proxmox | N | Y | Install certs in Proxmox Virtualization servers |
postfix | N | Y | STARTTLS Everywhere is becoming a Certbot Postfix/Exim plugin |
heroku | Y | Y | Integration with Heroku SSL |
If you’re interested, you can also write your own plugin.
Managing certificates¶
To view a list of the certificates Certbot knows about, run
the certificates
subcommand:
certbot certificates
This returns information in the following format:
Found the following certs:
Certificate Name: example.com
Domains: example.com, www.example.com
Expiry Date: 2017-02-19 19:53:00+00:00 (VALID: 30 days)
Certificate Path: /etc/letsencrypt/live/example.com/fullchain.pem
Private Key Path: /etc/letsencrypt/live/example.com/privkey.pem
Certificate Name
shows the name of the certificate. Pass this name
using the --cert-name
flag to specify a particular certificate for the run
,
certonly
, certificates
, renew
, and delete
commands. Example:
certbot certonly --cert-name example.com
Re-creating and Updating Existing Certificates¶
You can use certonly
or run
subcommands to request
the creation of a single new certificate even if you already have an
existing certificate with some of the same domain names.
If a certificate is requested with run
or certonly
specifying a
certificate name that already exists, Certbot updates
the existing certificate. Otherwise a new certificate
is created and assigned the specified name.
The --force-renewal
, --duplicate
, and --expand
options
control Certbot’s behavior when re-creating
a certificate with the same name as an existing certificate.
If you don’t specify a requested behavior, Certbot may ask you what you intended.
--force-renewal
tells Certbot to request a new certificate
with the same domains as an existing certificate. Each domain
must be explicitly specified via -d
. If successful, this certificate
is saved alongside the earlier one and symbolic links (the “live
”
reference) will be updated to point to the new certificate. This is a
valid method of renewing a specific individual
certificate.
--duplicate
tells Certbot to create a separate, unrelated certificate
with the same domains as an existing certificate. This certificate is
saved completely separately from the prior one. Most users will not
need to issue this command in normal circumstances.
--expand
tells Certbot to update an existing certificate with a new
certificate that contains all of the old domains and one or more additional
new domains.
--allow-subset-of-names
tells Certbot to continue with certificate generation if
only some of the specified domain authorizations can be obtained. This may
be useful if some domains specified in a certificate no longer point at this
system.
Whenever you obtain a new certificate in any of these ways, the new certificate exists alongside any previously obtained certificates, whether or not the previous certificates have expired. The generation of a new certificate counts against several rate limits that are intended to prevent abuse of the ACME protocol, as described here.
Changing a Certificate’s Domains¶
The --cert-name
flag can also be used to modify the domains a certificate contains,
by specifying new domains using the -d
or --domains
flag. If certificate example.com
previously contained example.com
and www.example.com
, it can be modified to only
contain example.com
by specifying only example.com
with the -d
or --domains
flag. Example:
certbot certonly --cert-name example.com -d example.com
The same format can be used to expand the set of domains a certificate contains, or to replace that set entirely:
certbot certonly --cert-name example.com -d example.org,www.example.org
Revoking certificates¶
If your account key has been compromised or you otherwise need to revoke a certificate,
use the revoke
command to do so. Note that the revoke
command takes the certificate path
(ending in cert.pem
), not a certificate name or domain. Example:
certbot revoke --cert-path /etc/letsencrypt/live/CERTNAME/cert.pem
Additionally, if a certificate
is a test cert obtained via the --staging
or --test-cert
flag, that flag must be passed to the
revoke
subcommand.
Once a certificate is revoked (or for other cert management tasks), all of a certificate’s
relevant files can be removed from the system with the delete
subcommand:
certbot delete --cert-name example.com
Note
If you don’t use delete
to remove the certificate completely, it will be renewed automatically at the next renewal event.
Renewing certificates¶
Note
Let’s Encrypt CA issues short-lived certificates (90 days). Make sure you renew the certificates at least once in 3 months.
As of version 0.10.0, Certbot supports a renew
action to check
all installed certificates for impending expiry and attempt to renew
them. The simplest form is simply
certbot renew
This command attempts to renew any previously-obtained certificates that
expire in less than 30 days. The same plugin and options that were used
at the time the certificate was originally issued will be used for the
renewal attempt, unless you specify other plugins or options. Unlike certonly
, renew
acts on
multiple certificates and always takes into account whether each one is near
expiry. Because of this, renew
is suitable (and designed) for automated use,
to allow your system to automatically renew each certificate when appropriate.
Since renew
only renews certificates that are near expiry it can be
run as frequently as you want - since it will usually take no action.
The renew
command includes hooks for running commands or scripts before or after a certificate is
renewed. For example, if you have a single cert obtained using
the standalone plugin, you might need to stop the webserver
before renewing so standalone can bind to the necessary ports, and
then restart it after the plugin is finished. Example:
certbot renew --pre-hook "service nginx stop" --post-hook "service nginx start"
The hooks will only be
run if a certificate is due for renewal, so you can run this command
frequently without unnecessarily stopping your webserver. More
information about renewal hooks can be found by running
certbot --help renew
.
If you’re sure that this command executes successfully without human
intervention, you can add the command to crontab
(since certificates
are only renewed when they’re determined to be near expiry, the command
can run on a regular basis, like every week or every day). In that case,
you are likely to want to use the -q
or --quiet
quiet flag to
silence all output except errors.
If you are manually renewing all of your certificates, the
--force-renewal
flag may be helpful; it causes the expiration time of
the certificate(s) to be ignored when considering renewal, and attempts to
renew each and every installed certificate regardless of its age. (This
form is not appropriate to run daily because each certificate will be
renewed every day, which will quickly run into the certificate authority
rate limit.)
Note that options provided to certbot renew
will apply to
every certificate for which renewal is attempted; for example,
certbot renew --rsa-key-size 4096
would try to replace every
near-expiry certificate with an equivalent certificate using a 4096-bit
RSA public key. If a certificate is successfully renewed using
specified options, those options will be saved and used for future
renewals of that certificate.
An alternative form that provides for more fine-grained control over the
renewal process (while renewing specified certificates one at a time),
is certbot certonly
with the complete set of subject domains of
a specific certificate specified via -d
flags. You may also want to
include the -n
or --noninteractive
flag to prevent blocking on
user input (which is useful when running the command from cron).
certbot certonly -n -d example.com -d www.example.com
All of the domains covered by the certificate must be specified in
this case in order to renew and replace the old certificate rather
than obtaining a new one; don’t forget any www.
domains! Specifying
a subset of the domains creates a new, separate certificate containing
only those domains, rather than replacing the original certificate.
When run with a set of domains corresponding to an existing certificate,
the certonly
command attempts to renew that specific certificate.
Please note that the CA will send notification emails to the address you provide if you do not renew certificates that are about to expire.
Certbot is working hard to improve the renewal process, and we apologize for any inconvenience you encounter in integrating these commands into your individual environment.
Note
certbot renew
exit status will only be 1 if a renewal attempt failed.
This means certbot renew
exit status will be 0 if no cert needs to be updated.
If you write a custom script and expect to run a command only after a cert was actually renewed
you will need to use the --post-hook
since the exit status will be 0 both on successful renewal
and when renewal is not necessary.
Modifying the Renewal Configuration File¶
For advanced certificate management tasks, it is possible to manually modify the certificate’s
renewal configuration file, located at /etc/letsencrypt/renewal/CERTNAME
.
Warning
Modifying any files in /etc/letsencrypt
can damage them so Certbot can no longer properly manage its certificates, and we do not recommend doing so.
For most tasks, it is safest to limit yourself to pointing symlinks at the files there, or using
--renew-hook
to copy / make new files based upon those files, if your operational situation requires it
(for instance, combining certs and keys in different way, or having copies of things with different
specific permissions that are demanded by other programs).
If the contents of /etc/letsencrypt/archive/CERTNAME
are moved to a new folder, first specify
the new folder’s name in the renewal configuration file, then run certbot update_symlinks
to
point the symlinks in /etc/letsencrypt/live/CERTNAME
to the new folder.
If you would like the live certificate files whose symlink location Certbot updates on each run to
reside in a different location, first move them to that location, then specify the full path of
each of the four files in the renewal configuration file. Since the symlinks are relative links,
you must follow this with an invocation of certbot update_symlinks
.
For example, say that a certificate’s renewal configuration file previously contained the following directives:
archive_dir = /etc/letsencrypt/archive/example.com
cert = /etc/letsencrypt/live/example.com/cert.pem
privkey = /etc/letsencrypt/live/example.com/privkey.pem
chain = /etc/letsencrypt/live/example.com/chain.pem
fullchain = /etc/letsencrypt/live/example.com/fullchain.pem
The following commands could be used to specify where these files are located:
mv /etc/letsencrypt/archive/example.com /home/user/me/certbot/example_archive
sed -i 's,/etc/letsencrypt/archive/example.com,/home/user/me/certbot/example_archive,' /etc/letsencrypt/renewal/example.com.conf
mv /etc/letsencrypt/live/example.com/*.pem /home/user/me/certbot/
sed -i 's,/etc/letsencrypt/live/example.com,/home/user/me/certbot,g' /etc/letsencrypt/renewal/example.com.conf
certbot update_symlinks
Where are my certificates?¶
All generated keys and issued certificates can be found in
/etc/letsencrypt/live/$domain
. Rather than copying, please point
your (web) server configuration directly to those files (or create
symlinks). During the renewal, /etc/letsencrypt/live
is updated
with the latest necessary files.
Note
/etc/letsencrypt/archive
and /etc/letsencrypt/keys
contain all previous keys and certificates, while
/etc/letsencrypt/live
symlinks to the latest versions.
The following files are available:
privkey.pem
Private key for the certificate.
Warning
This must be kept secret at all times! Never share it with anyone, including Certbot developers. You cannot put it into a safe, however - your server still needs to access this file in order for SSL/TLS to work.
This is what Apache needs for SSLCertificateKeyFile, and Nginx for ssl_certificate_key.
fullchain.pem
All certificates, including server certificate (aka leaf certificate or end-entity certificate). The server certificate is the first one in this file, followed by any intermediates.
This is what Apache >= 2.4.8 needs for SSLCertificateFile, and what Nginx needs for ssl_certificate.
cert.pem
andchain.pem
(less common)cert.pem
contains the server certificate by itself, andchain.pem
contains the additional intermediate certificate or certificates that web browsers will need in order to validate the server certificate. If you provide one of these files to your web server, you must provide both of them, or some browsers will show “This Connection is Untrusted” errors for your site, some of the time.Apache < 2.4.8 needs these for SSLCertificateFile. and SSLCertificateChainFile, respectively.
If you’re using OCSP stapling with Nginx >= 1.3.7,
chain.pem
should be provided as the ssl_trusted_certificate to validate OCSP responses.
Note
All files are PEM-encoded.
If you need other format, such as DER or PFX, then you
could convert using openssl
. You can automate that with
--renew-hook
if you’re using automatic renewal.
Pre and Post Validation Hooks¶
Certbot allows for the specification of pre and post validation hooks when run
in manual mode. The flags to specify these scripts are --manual-auth-hook
and --manual-cleanup-hook
respectively and can be used as follows:
certbot certonly --manual --manual-auth-hook /path/to/http/authenticator.sh --manual-cleanup-hook /path/to/http/cleanup.sh -d secure.example.com
This will run the authenticator.sh
script, attempt the validation, and then run
the cleanup.sh
script. Additionally certbot will pass three environment
variables to these scripts:
CERTBOT_DOMAIN
: The domain being authenticatedCERTBOT_VALIDATION
: The validation stringCERTBOT_TOKEN
: Resource name part of the HTTP-01 challenge (HTTP-01 only)
Additionally for cleanup:
CERTBOT_AUTH_OUTPUT
: Whatever the auth script wrote to stdout
Example usage for HTTP-01:
certbot certonly --manual --preferred-challenges=http --manual-auth-hook /path/to/http/authenticator.sh --manual-cleanup-hook /path/to/http/cleanup.sh -d secure.example.com
/path/to/http/authenticator.sh
#!/bin/bash
echo $CERTBOT_VALIDATION > /var/www/htdocs/.well-known/acme-challenge/$CERTBOT_TOKEN
/path/to/http/cleanup.sh
#!/bin/bash
rm -f /var/www/htdocs/.well-known/acme-challenge/$CERTBOT_TOKEN
Example usage for DNS-01 (Cloudflare API v4) (for example purposes only, do not use as-is)
certbot certonly --manual --preferred-challenges=dns --manual-auth-hook /path/to/dns/authenticator.sh --manual-cleanup-hook /path/to/dns/cleanup.sh -d secure.example.com
/path/to/dns/authenticator.sh
#!/bin/bash
# Get your API key from https://www.cloudflare.com/a/account/my-account
API_KEY="your-api-key"
EMAIL="your.email@example.com"
# Strip only the top domain to get the zone id
DOMAIN=$(expr match "$CERTBOT_DOMAIN" '.*\.\(.*\..*\)')
# Get the Cloudflare zone id
ZONE_EXTRA_PARAMS="status=active&page=1&per_page=20&order=status&direction=desc&match=all"
ZONE_ID=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=$DOMAIN&$ZONE_EXTRA_PARAMS" \
-H "X-Auth-Email: $EMAIL" \
-H "X-Auth-Key: $API_KEY" \
-H "Content-Type: application/json" | python -c "import sys,json;print(json.load(sys.stdin)['result'][0]['id'])")
# Create TXT record
CREATE_DOMAIN="_acme-challenge.$CERTBOT_DOMAIN"
RECORD_ID=$(curl -s -X POST "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/dns_records" \
-H "X-Auth-Email: $EMAIL" \
-H "X-Auth-Key: $API_KEY" \
-H "Content-Type: application/json" \
--data '{"type":"TXT","name":"'"$CREATE_DOMAIN"'","content":"'"$CERTBOT_VALIDATION"'","ttl":120}' \
| python -c "import sys,json;print(json.load(sys.stdin)['result']['id'])")
# Save info for cleanup
if [ ! -d /tmp/CERTBOT_$CERTBOT_DOMAIN ];then
mkdir -m 0700 /tmp/CERTBOT_$CERTBOT_DOMAIN
fi
echo $ZONE_ID > /tmp/CERTBOT_$CERTBOT_DOMAIN/ZONE_ID
echo $RECORD_ID > /tmp/CERTBOT_$CERTBOT_DOMAIN/RECORD_ID
# Sleep to make sure the change has time to propagate over to DNS
sleep 25
/path/to/dns/cleanup.sh
#!/bin/bash
# Get your API key from https://www.cloudflare.com/a/account/my-account
API_KEY="your-api-key"
EMAIL="your.email@example.com"
if [ -f /tmp/CERTBOT_$CERTBOT_DOMAIN/ZONE_ID ]; then
ZONE_ID=$(cat /tmp/CERTBOT_$CERTBOT_DOMAIN/ZONE_ID)
rm -f /tmp/CERTBOT_$CERTBOT_DOMAIN/ZONE_ID
fi
if [ -f /tmp/CERTBOT_$CERTBOT_DOMAIN/RECORD_ID ]; then
RECORD_ID=$(cat /tmp/CERTBOT_$CERTBOT_DOMAIN/RECORD_ID)
rm -f /tmp/CERTBOT_$CERTBOT_DOMAIN/RECORD_ID
fi
# Remove the challenge TXT record from the zone
if [ -n "${ZONE_ID}" ]; then
if [ -n "${RECORD_ID}" ]; then
curl -s -X DELETE "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/dns_records/$RECORD_ID" \
-H "X-Auth-Email: $EMAIL" \
-H "X-Auth-Key: $API_KEY" \
-H "Content-Type: application/json"
fi
fi
Configuration file¶
It is possible to specify configuration file with
certbot-auto --config cli.ini
(or shorter -c cli.ini
). An
example configuration file is shown below:
# This is an example of the kind of things you can do in a configuration file.
# All flags used by the client can be configured here. Run Certbot with
# "--help" to learn more about the available options.
# Use a 4096 bit RSA key instead of 2048
rsa-key-size = 4096
# Uncomment and update to register with the specified e-mail address
# email = foo@example.com
# Uncomment and update to generate certificates for the specified
# domains.
# domains = example.com, www.example.com
# Uncomment to use a text interface instead of ncurses
# text = True
# Uncomment to use the standalone authenticator on port 443
# authenticator = standalone
# standalone-supported-challenges = tls-sni-01
# Uncomment to use the webroot authenticator. Replace webroot-path with the
# path to the public_html / webroot folder being served by your web server.
# authenticator = webroot
# webroot-path = /usr/share/nginx/html
By default, the following locations are searched:
/etc/letsencrypt/cli.ini
$XDG_CONFIG_HOME/letsencrypt/cli.ini
(or~/.config/letsencrypt/cli.ini
if$XDG_CONFIG_HOME
is not set).
Certbot command-line options¶
Certbot supports a lot of command line options. Here’s the full list, from
certbot --help all
:
usage:
certbot [SUBCOMMAND] [options] [-d DOMAIN] [-d DOMAIN] ...
Certbot can obtain and install HTTPS/TLS/SSL certificates. By default,
it will attempt to use a webserver both for obtaining and installing the
cert. The most common SUBCOMMANDS and flags are:
obtain, install, and renew certificates:
(default) run Obtain & install a cert in your current webserver
certonly Obtain or renew a cert, but do not install it
renew Renew all previously obtained certs that are near expiry
-d DOMAINS Comma-separated list of domains to obtain a cert for
--apache Use the Apache plugin for authentication & installation
--standalone Run a standalone webserver for authentication
--nginx Use the Nginx plugin for authentication & installation
--webroot Place files in a server's webroot folder for authentication
--manual Obtain certs interactively, or using shell script hooks
-n Run non-interactively
--test-cert Obtain a test cert from a staging server
--dry-run Test "renew" or "certonly" without saving any certs to disk
manage certificates:
certificates Display information about certs you have from Certbot
revoke Revoke a certificate (supply --cert-path)
delete Delete a certificate
manage your account with Let's Encrypt:
register Create a Let's Encrypt ACME account
--agree-tos Agree to the ACME server's Subscriber Agreement
-m EMAIL Email address for important account notifications
optional arguments:
-h, --help show this help message and exit
-c CONFIG_FILE, --config CONFIG_FILE
path to config file (default: /etc/letsencrypt/cli.ini
and ~/.config/letsencrypt/cli.ini)
-v, --verbose This flag can be used multiple times to incrementally
increase the verbosity of output, e.g. -vvv. (default:
-2)
-n, --non-interactive, --noninteractive
Run without ever asking for user input. This may
require additional command line flags; the client will
try to explain which ones are required if it finds one
missing (default: False)
--force-interactive Force Certbot to be interactive even if it detects
it's not being run in a terminal. This flag cannot be
used with the renew subcommand. (default: False)
-d DOMAIN, --domains DOMAIN, --domain DOMAIN
Domain names to apply. For multiple domains you can
use multiple -d flags or enter a comma separated list
of domains as a parameter. (default: Ask)
--cert-name CERTNAME Certificate name to apply. Only one certificate name
can be used per Certbot run. To see certificate names,
run 'certbot certificates'. When creating a new
certificate, specifies the new certificate's name.
(default: None)
--dry-run Perform a test run of the client, obtaining test
(invalid) certs but not saving them to disk. This can
currently only be used with the 'certonly' and 'renew'
subcommands. Note: Although --dry-run tries to avoid
making any persistent changes on a system, it is not
completely side-effect free: if used with webserver
authenticator plugins like apache and nginx, it makes
and then reverts temporary config changes in order to
obtain test certs, and reloads webservers to deploy
and then roll back those changes. It also calls --pre-
hook and --post-hook commands if they are defined
because they may be necessary to accurately simulate
renewal. --renew-hook commands are not called.
(default: False)
--preferred-challenges PREF_CHALLS
A sorted, comma delimited list of the preferred
challenge to use during authorization with the most
preferred challenge listed first (Eg, "dns" or "tls-
sni-01,http,dns"). Not all plugins support all
challenges. See
https://certbot.eff.org/docs/using.html#plugins for
details. ACME Challenges are versioned, but if you
pick "http" rather than "http-01", Certbot will select
the latest version automatically. (default: [])
--user-agent USER_AGENT
Set a custom user agent string for the client. User
agent strings allow the CA to collect high level
statistics about success rates by OS and plugin. If
you wish to hide your server OS version from the Let's
Encrypt server, set this to "". (default:
CertbotACMEClient/0.12.0 (Ubuntu 16.04.2 LTS)
Authenticator/XXX Installer/YYY)
automation:
Arguments for automating execution & other tweaks
--keep-until-expiring, --keep, --reinstall
If the requested cert matches an existing cert, always
keep the existing one until it is due for renewal (for
the 'run' subcommand this means reinstall the existing
cert). (default: Ask)
--expand If an existing cert covers some subset of the
requested names, always expand and replace it with the
additional names. (default: Ask)
--version show program's version number and exit
--force-renewal, --renew-by-default
If a certificate already exists for the requested
domains, renew it now, regardless of whether it is
near expiry. (Often --keep-until-expiring is more
appropriate). Also implies --expand. (default: False)
--renew-with-new-domains
If a certificate already exists for the requested
certificate name but does not match the requested
domains, renew it now, regardless of whether it is
near expiry. (default: False)
--allow-subset-of-names
When performing domain validation, do not consider it
a failure if authorizations can not be obtained for a
strict subset of the requested domains. This may be
useful for allowing renewals for multiple domains to
succeed even if some domains no longer point at this
system. This option cannot be used with --csr.
(default: False)
--agree-tos Agree to the ACME Subscriber Agreement (default: Ask)
--duplicate Allow making a certificate lineage that duplicates an
existing one (both can be renewed in parallel)
(default: False)
--os-packages-only (certbot-auto only) install OS package dependencies
and then stop (default: False)
--no-self-upgrade (certbot-auto only) prevent the certbot-auto script
from upgrading itself to newer released versions
(default: Upgrade automatically)
-q, --quiet Silence all output except errors. Useful for
automation via cron. Implies --non-interactive.
(default: False)
security:
Security parameters & server settings
--rsa-key-size N Size of the RSA key. (default: 2048)
--must-staple Adds the OCSP Must Staple extension to the
certificate. Autoconfigures OCSP Stapling for
supported setups (Apache version >= 2.3.3 ). (default:
False)
--redirect Automatically redirect all HTTP traffic to HTTPS for
the newly authenticated vhost. (default: Ask)
--no-redirect Do not automatically redirect all HTTP traffic to
HTTPS for the newly authenticated vhost. (default:
Ask)
--hsts Add the Strict-Transport-Security header to every HTTP
response. Forcing browser to always use SSL for the
domain. Defends against SSL Stripping. (default:
False)
--uir Add the "Content-Security-Policy: upgrade-insecure-
requests" header to every HTTP response. Forcing the
browser to use https:// for every http:// resource.
(default: None)
--staple-ocsp Enables OCSP Stapling. A valid OCSP response is
stapled to the certificate that the server offers
during TLS. (default: None)
--strict-permissions Require that all configuration files are owned by the
current user; only needed if your config is somewhere
unsafe like /tmp/ (default: False)
testing:
The following flags are meant for testing and integration purposes only.
--test-cert, --staging
Use the staging server to obtain or revoke test
(invalid) certs; equivalent to --server https://acme-
staging.api.letsencrypt.org/directory (default: False)
--debug Show tracebacks in case of errors, and allow certbot-
auto execution on experimental platforms (default:
False)
--no-verify-ssl Disable verification of the ACME server's certificate.
(default: False)
--tls-sni-01-port TLS_SNI_01_PORT
Port used during tls-sni-01 challenge. This only
affects the port Certbot listens on. A conforming ACME
server will still attempt to connect on port 443.
(default: 443)
--http-01-port HTTP01_PORT
Port used in the http-01 challenge. This only affects
the port Certbot listens on. A conforming ACME server
will still attempt to connect on port 80. (default:
80)
--break-my-certs Be willing to replace or renew valid certs with
invalid (testing/staging) certs (default: False)
paths:
Arguments changing execution paths & servers
--cert-path CERT_PATH
Path to where cert is saved (with auth --csr),
installed from, or revoked. (default: None)
--key-path KEY_PATH Path to private key for cert installation or
revocation (if account key is missing) (default: None)
--chain-path CHAIN_PATH
Accompanying path to a certificate chain. (default:
None)
--config-dir CONFIG_DIR
Configuration directory. (default: /etc/letsencrypt)
--work-dir WORK_DIR Working directory. (default: /var/lib/letsencrypt)
--logs-dir LOGS_DIR Logs directory. (default: /var/log/letsencrypt)
--server SERVER ACME Directory Resource URI. (default:
https://acme-v01.api.letsencrypt.org/directory)
manage:
Various subcommands and flags are available for managing your
certificates:
certificates List certificates managed by Certbot
delete Clean up all files related to a certificate
renew Renew all certificates (or one specified with --cert-
name)
revoke Revoke a certificate specified with --cert-path
update_symlinks Recreate symlinks in your /etc/letsencrypt/live/
directory
run:
Options for obtaining & installing certs
certonly:
Options for modifying how a cert is obtained
--csr CSR Path to a Certificate Signing Request (CSR) in DER or
PEM format. Currently --csr only works with the
'certonly' subcommand. (default: None)
renew:
The 'renew' subcommand will attempt to renew all certificates (or more
precisely, certificate lineages) you have previously obtained if they are
close to expiry, and print a summary of the results. By default, 'renew'
will reuse the options used to create obtain or most recently successfully
renew each certificate lineage. You can try it with `--dry-run` first. For
more fine-grained control, you can renew individual lineages with the
`certonly` subcommand. Hooks are available to run commands before and
after renewal; see https://certbot.eff.org/docs/using.html#renewal for
more information on these.
--pre-hook PRE_HOOK Command to be run in a shell before obtaining any
certificates. Intended primarily for renewal, where it
can be used to temporarily shut down a webserver that
might conflict with the standalone plugin. This will
only be called if a certificate is actually to be
obtained/renewed. When renewing several certificates
that have identical pre-hooks, only the first will be
executed. (default: None)
--post-hook POST_HOOK
Command to be run in a shell after attempting to
obtain/renew certificates. Can be used to deploy
renewed certificates, or to restart any servers that
were stopped by --pre-hook. This is only run if an
attempt was made to obtain/renew a certificate. If
multiple renewed certificates have identical post-
hooks, only one will be run. (default: None)
--renew-hook RENEW_HOOK
Command to be run in a shell once for each
successfully renewed certificate. For this command,
the shell variable $RENEWED_LINEAGE will point to the
config live subdirectory containing the new certs and
keys; the shell variable $RENEWED_DOMAINS will contain
a space-delimited list of renewed cert domains
(default: None)
--disable-hook-validation
Ordinarily the commands specified for --pre-hook
/--post-hook/--renew-hook will be checked for
validity, to see if the programs being run are in the
$PATH, so that mistakes can be caught early, even when
the hooks aren't being run just yet. The validation is
rather simplistic and fails if you use more advanced
shell constructs, so you can use this switch to
disable it. (default: False)
certificates:
List certificates managed by Certbot
delete:
Options for deleting a certificate
revoke:
Options for revocation of certs
--reason {keycompromise,affiliationchanged,superseded,unspecified,cessationofoperation}
Specify reason for revoking certificate. (default: 0)
register:
Options for account registration & modification
--register-unsafely-without-email
Specifying this flag enables registering an account
with no email address. This is strongly discouraged,
because in the event of key loss or account compromise
you will irrevocably lose access to your account. You
will also be unable to receive notice about impending
expiration or revocation of your certificates. Updates
to the Subscriber Agreement will still affect you, and
will be effective 14 days after posting an update to
the web site. (default: False)
--update-registration
With the register verb, indicates that details
associated with an existing registration, such as the
e-mail address, should be updated, rather than
registering a new account. (default: False)
-m EMAIL, --email EMAIL
Email used for registration and recovery contact.
(default: Ask)
--eff-email Share your e-mail address with EFF (default: None)
--no-eff-email Don't share your e-mail address with EFF (default:
None)
unregister:
Options for account deactivation.
--account ACCOUNT_ID Account ID to use (default: None)
install:
Options for modifying how a cert is deployed
--fullchain-path FULLCHAIN_PATH
Accompanying path to a full certificate chain (cert
plus chain). (default: None)
config_changes:
Options for controlling which changes are displayed
--num NUM How many past revisions you want to be displayed
(default: None)
rollback:
Options for rolling back server configuration changes
--checkpoints N Revert configuration N number of checkpoints.
(default: 1)
plugins:
Options for for the "plugins" subcommand
--init Initialize plugins. (default: False)
--prepare Initialize and prepare plugins. (default: False)
--authenticators Limit to authenticator plugins only. (default: None)
--installers Limit to installer plugins only. (default: None)
update_symlinks:
Recreates cert and key symlinks in /etc/letsencrypt/live, if you changed
them by hand or edited a renewal configuration file
plugins:
Plugin Selection: Certbot client supports an extensible plugins
architecture. See 'certbot plugins' for a list of all installed plugins
and their names. You can force a particular plugin by setting options
provided below. Running --help <plugin_name> will list flags specific to
that plugin.
--configurator CONFIGURATOR
Name of the plugin that is both an authenticator and
an installer. Should not be used together with
--authenticator or --installer. (default: Ask)
-a AUTHENTICATOR, --authenticator AUTHENTICATOR
Authenticator plugin name. (default: None)
-i INSTALLER, --installer INSTALLER
Installer plugin name (also used to find domains).
(default: None)
--apache Obtain and install certs using Apache (default: False)
--nginx Obtain and install certs using Nginx (default: False)
--standalone Obtain certs using a "standalone" webserver. (default:
False)
--manual Provide laborious manual instructions for obtaining a
cert (default: False)
--webroot Obtain certs by placing files in a webroot directory.
(default: False)
nginx:
Nginx Web Server plugin - Alpha
--nginx-server-root NGINX_SERVER_ROOT
Nginx server root directory. (default: /etc/nginx)
--nginx-ctl NGINX_CTL
Path to the 'nginx' binary, used for 'configtest' and
retrieving nginx version number. (default: nginx)
standalone:
Spin up a temporary webserver
manual:
Authenticate through manual configuration or custom shell scripts. When
using shell scripts, an authenticator script must be provided. The
environment variables available to this script are $CERTBOT_DOMAIN which
contains the domain being authenticated, $CERTBOT_VALIDATION which is the
validation string, and $CERTBOT_TOKEN which is the filename of the
resource requested when performing an HTTP-01 challenge. An additional
cleanup script can also be provided and can use the additional variable
$CERTBOT_AUTH_OUTPUT which contains the stdout output from the auth
script.
--manual-auth-hook MANUAL_AUTH_HOOK
Path or command to execute for the authentication
script (default: None)
--manual-cleanup-hook MANUAL_CLEANUP_HOOK
Path or command to execute for the cleanup script
(default: None)
--manual-public-ip-logging-ok
Automatically allows public IP logging (default: Ask)
webroot:
Place files in webroot directory
--webroot-path WEBROOT_PATH, -w WEBROOT_PATH
public_html / webroot path. This can be specified
multiple times to handle different domains; each
domain will have the webroot path that preceded it.
For instance: `-w /var/www/example -d example.com -d
www.example.com -w /var/www/thing -d thing.net -d
m.thing.net` (default: Ask)
--webroot-map WEBROOT_MAP
JSON dictionary mapping domains to webroot paths; this
implies -d for each entry. You may need to escape this
from your shell. E.g.: --webroot-map
'{"eg1.is,m.eg1.is":"/www/eg1/", "eg2.is":"/www/eg2"}'
This option is merged with, but takes precedence over,
-w / -d entries. At present, if you put webroot-map in
a config file, it needs to be on a single line, like:
webroot-map = {"example.com":"/var/www"}. (default:
{})
apache:
Apache Web Server plugin - Beta
--apache-enmod APACHE_ENMOD
Path to the Apache 'a2enmod' binary. (default:
a2enmod)
--apache-dismod APACHE_DISMOD
Path to the Apache 'a2dismod' binary. (default:
a2dismod)
--apache-le-vhost-ext APACHE_LE_VHOST_EXT
SSL vhost configuration extension. (default: -le-
ssl.conf)
--apache-server-root APACHE_SERVER_ROOT
Apache server root directory. (default: /etc/apache2)
--apache-vhost-root APACHE_VHOST_ROOT
Apache server VirtualHost configuration root (default:
/etc/apache2/sites-available)
--apache-logs-root APACHE_LOGS_ROOT
Apache server logs directory (default:
/var/log/apache2)
--apache-challenge-location APACHE_CHALLENGE_LOCATION
Directory path for challenge configuration. (default:
/etc/apache2)
--apache-handle-modules APACHE_HANDLE_MODULES
Let installer handle enabling required modules for
you.(Only Ubuntu/Debian currently) (default: True)
--apache-handle-sites APACHE_HANDLE_SITES
Let installer handle enabling sites for you.(Only
Ubuntu/Debian currently) (default: True)
null:
Null Installer
Getting help¶
If you’re having problems, we recommend posting on the Let’s Encrypt Community Forum.
You can also chat with us on IRC: (#certbot @ OFTC) or (#letsencrypt @ freenode).
If you find a bug in the software, please do report it in our issue tracker. Remember to give us as much information as possible:
- copy and paste exact command line used and the output (though mind that the latter might include some personally identifiable information, including your email and domains)
- copy and paste logs from
/var/log/letsencrypt
(though mind they also might contain personally identifiable information) - copy and paste
certbot --version
output - your operating system, including specific version
- specify which installation method you’ve chosen