19.3.1 Setting Up 复制 to Use Encrypted Connections
To use an encrypted connection for the transfer of the binary log required during replication, both the source and the replica servers must support encrypted network connections. If either server does not support encrypted connections (because it has not been compiled or configured for them), replication through an encrypted connection is not possible.
Setting up encrypted connections for replication is similar to doing so for client/server connections. You must obtain (or create) a suitable security certificate that you can use on the source, and a similar certificate (from the same certificate authority) on each replica. You must also obtain suitable key files.
For more information on setting up a server and client for encrypted connections, see Section 8.3.1, “Configuring MySQL to Use Encrypted Connections”.
To enable encrypted connections on the source, you must create or obtain suitable certificate and key files, and then add the following configuration parameters to the [mysqld]
section of the source my.cnf
file, changing the file names as necessary:
[mysqld]
ssl_ca=cacert.pem
ssl_cert=server-cert.pem
ssl_key=server-key.pem
The paths to the files may be relative or absolute; we recommend that you always use complete paths for this purpose.
The configuration parameters are as follows:
-
ssl_ca
: The path name of the Certificate Authority (CA) certificate file. (ssl_capath
is similar but specifies the path name of a directory of CA certificate files.) -
ssl_cert
: The path name of the server public key certificate file. This certificate can be sent to the client and authenticated against the CA certificate that it has. -
ssl_key
: The path name of the server private key file.
To enable encrypted connections on the replica, use the CHANGE REPLICATION SOURCE TO
statement.
-
To name the replica's certificate and SSL private key files using
CHANGE REPLICATION SOURCE TO
, add the appropriateSOURCE_SSL_
options, like this:xxx
-> SOURCE_SSL_CA = 'ca_file_name', -> SOURCE_SSL_CAPATH = 'ca_directory_name', -> SOURCE_SSL_CERT = 'cert_file_name', -> SOURCE_SSL_KEY = 'key_file_name',
These options correspond to the
--ssl-
options with the same names, as described in Command Options for Encrypted Connections. For these options to take effect,xxx
SOURCE_SSL=1
must also be set. For a replication connection, specifying a value for either ofSOURCE_SSL_CA
orSOURCE_SSL_CAPATH
corresponds to setting--ssl-mode=VERIFY_CA
. The connection attempt succeeds only if a valid matching Certificate Authority (CA) certificate is found using the specified information. -
To activate host name identity verification, add the
SOURCE_SSL_VERIFY_SERVER_CERT
option, like this:-> SOURCE_SSL_VERIFY_SERVER_CERT=1,
For a replication connection, specifying
SOURCE_SSL_VERIFY_SERVER_CERT=1
corresponds to setting--ssl-mode=VERIFY_IDENTITY
, as described in Command Options for Encrypted Connections. For this option to take effect,SOURCE_SSL=1
must also be set. Host name identity verification does not work with self-signed certificates. -
To activate certificate revocation list (CRL) checks, add the
SOURCE_SSL_CRL
orSOURCE_SSL_CRLPATH
option, as shown here:-> SOURCE_SSL_CRL = 'crl_file_name', -> SOURCE_SSL_CRLPATH = 'crl_directory_name',
These options correspond to the
--ssl-
options with the same names, as described in Command Options for Encrypted Connections. If they are not specified, no CRL checking takes place.xxx
-
To specify lists of ciphers, ciphersuites, and encryption protocols permitted by the replica for the replication connection, use the
SOURCE_SSL_CIPHER
,SOURCE_TLS_VERSION
, andSOURCE_TLS_CIPHERSUITES
options, like this:-> SOURCE_SSL_CIPHER = 'cipher_list', -> SOURCE_TLS_VERSION = 'protocol_list', -> SOURCE_TLS_CIPHERSUITES = 'ciphersuite_list',
-
The
SOURCE_SSL_CIPHER
option specifies a colon-separated list of one or more ciphers permitted by the replica for the replication connection. -
The
SOURCE_TLS_VERSION
option specifies a comma-separated list of the TLS encryption protocols permitted by the replica for the replication connection, in a format like that for thetls_version
server system variable. The connection procedure negotiates the use of the highest TLS version that both the source and the replica permit. To be able to connect, the replica must have at least one TLS version in common with the source. -
The
SOURCE_TLS_CIPHERSUITES
option specifies a colon-separated list of one or more ciphersuites that are permitted by the replica for the replication connection if TLSv1.3 is used for the connection. If this option is set toNULL
when TLSv1.3 is used (which is the default if you do not set the option), the ciphersuites that are enabled by default are allowed. If you set the option to an empty string, no cipher suites are allowed, and TLSv1.3 is therefore not used.
The protocols, ciphers, and ciphersuites that you can specify in these lists depend on the SSL library used to compile MySQL. For information about the formats, the permitted values, and the defaults if you do not specify the options, see Section 8.3.2, “Encrypted Connection TLS Protocols and Ciphers”.
NoteYou can use the
SOURCE_TLS_CIPHERSUITES
option to specify any selection of ciphersuites, including only non-default ciphersuites if you want. -
-
After the source information has been updated, start the replication process on the replica, like this:
mysql> START REPLICA;
You can use the
SHOW REPLICA STATUS
statement to confirm that an encrypted connection was established successfully. -
Requiring encrypted connections on the replica does not ensure that the source requires encrypted connections from replicas. If you want to ensure that the source only accepts replicas that connect using encrypted connections, create a replication user account on the source using the
REQUIRE SSL
option, then grant that user theREPLICATION SLAVE
privilege. For example:mysql> CREATE USER 'repl'@'%.example.com' IDENTIFIED BY 'password' -> REQUIRE SSL; mysql> GRANT REPLICATION SLAVE ON *.* -> TO 'repl'@'%.example.com';
If you have an existing replication user account on the source, you can add
REQUIRE SSL
to it with this statement:mysql> ALTER USER 'repl'@'%.example.com' REQUIRE SSL;