x.509
MongoDB supports x.509 certificate authentication for client authentication and internal authentication of the members of replica sets and sharded clusters.
x.509 certificate authentication requires a secure TLS/SSL connection.
Certificate Authority
For production use, your MongoDB deployment should use valid certificates generated and signed by a certificate authority. You or your organization can generate and maintain an independent certificate authority, or use certificates generated by third-party TLS vendors. Obtaining and managing certificates is beyond the scope of this documentation.
Client x.509 Certificates
To authenticate to servers, clients can use x.509 certificates instead of usernames and passwords.
Client Certificate Requirements
Client certificate requirements:
A single Certificate Authority (CA) must issue the certificates for both the client and the server.
Each unique MongoDB user must have a unique certificate.
The x.509 certificate must not be expired.
Client certificates must contain the following fields:
keyUsage = digitalSignature extendedKeyUsage = clientAuth At least one of the following client certificate attributes must be different than the attributes in both the
net.tls.clusterFile
andnet.tls.certificateKeyFile
server certificates:Organization (
O
)Organizational Unit (
OU
)Domain Component (
DC
)
The
subject
of a client x.509 certificate, which contains the Distinguished Name (DN
), must be different than thesubject
s of member x.509 certificates. If the MongoDB deployment hastlsX509ClusterAuthDNOverride
set, the client x.509 certificate's subject must not match that value.Important
If a client x.509 certificate's subject matches the
O
,OU
, andDC
attributes of the Member x.509 Certificate (ortlsX509ClusterAuthDNOverride
, if set) exactly, the client connection is accepted, full permissions are granted, and a warning message appears in the log.Only cluster member x509 certificates should use the same
O
,OU
, andDC
attribute combinations.
MongoDB User and $external
Database
To authenticate with a client certificate, you must first add the client
certificate's subject
as a MongoDB user in the $external
database.
The $external
database is the Authentication Database for the user.
Each unique x.509 client certificate is for one MongoDB user. You cannot use a single client certificate to authenticate more than one MongoDB user.
To use Client Sessions and Causal Consistency Guarantees with $external
authentication users
(Kerberos, LDAP, or x.509 users), usernames cannot be greater
than 10k bytes.
TLS Connection X509 Certificate Startup Warning
Starting in MongoDB 5.0, mongod
and mongos
now
issue a startup warning when their certificates do not include a
Subject Alternative Name attribute.
The following platforms do not support common name validation:
iOS 13 and higher
MacOS 10.15 and higher
Go 1.15 and higher
Clients using these platforms will not authenticate to MongoDB servers that use x.509 certificates whose hostnames are specified by CommonName attributes.
Member x.509 Certificates
For internal authentication between members of sharded clusters and replica sets, you can use x.509 certificates instead of keyfiles.
Member Certificate Requirements
Use member certificates to verify membership to a sharded
cluster or a replica set. Member certificate file paths are
configured with the net.tls.clusterFile
and
net.tls.certificateKeyFile
options. Members have the
following configuration requirements:
Cluster member configuration must specify a non-empty value for at least one of the attributes used for authentication. By default, MongoDB accepts:
the Organization (
O
)the Organizational Unit (
OU
)the Domain Component (
DC
)
You can specify alternative attributes to use for authentication by setting
net.tls.clusterAuthX509.extensionValue
.Cluster member configuration must include the same
net.tls.clusterAuthX509.attributes
and use matching values. Attribute order doesn't matter. The following example setsO
andOU
, but notDC
:net: tls: clusterAuthX509: attributes: O=MongoDB, OU=MongoDB Server
The certificates have the following requirements:
A single Certificate Authority (CA) must issue all x.509 certificates for the members of a sharded cluster or a replica set.
At least one of the Subject Alternative Name (
SAN
) entries must match the server hostname used by other cluster members. When comparingSAN
s, MongoDB can compare either DNS names or IP addresses.If you don't specify
subjectAltName
, MongoDB compares the Common Name (CN) instead. However, this usage of CN is deprecated per RFC2818If the certificate used as the
certificateKeyFile
includesextendedKeyUsage
, the value must include bothclientAuth
("TLS Web Client Authentication") andserverAuth
("TLS Web Server Authentication").extendedKeyUsage = clientAuth, serverAuth If the certificate used as the
clusterFile
includesextendedKeyUsage
, the value must includeclientAuth
.extendedKeyUsage = clientAuth
MongoDB Configuration for Membership Authentication
You can use TLS for internal authentication between each member of
your replica set (each mongod
instance) or sharded
cluster (each mongod
and mongos
instance).
To use TLS for internal authentication, use the following settings:
security.clusterAuthMode
or--clusterAuthMode
set tox509
mongod
and mongos
instances use their certificate key files to
prove their identity to clients, but certificate key files can also be used for
membership authentication. If you do not specify a cluster file,
members use their certificate key files for membership authentication.
Specify the certificate key file with net.tls.certificateKeyFile
or
--tlsCertificateKeyFile
.
To use the certificate key file for both client authentication and membership authentication, the certificate must either:
Omit
extendedKeyUsage
orSpecify
extendedKeyUsage = serverAuth, clientAuth