Verify whether the signing authority is registered in the client's trust store.
To test whether the client will accept certificates signed by your certification authority, try to establish an SSL connection, as described above under Configuring and Running an SSL-Based Client Using Self-Signed Certificates. If the CA is in the client's trust store, the connection will succeed and you can skip the next step. If the connection fails with a certificate validation error, go on to the next step.
Install the signing CA’s root certificate in the client’s trust store.
The client searches the key store files cacerts and jssecacerts by default, so no further configuration is necessary if you install the certificate in either of those files. The following example installs a test root certificate from the Verisign certification authority from a file named testrootca.cer into the default system certificate file, cacerts. The example assumes that J2SE is installed in the directory $JAVA_HOME/usr/j2se:
keytool -import -keystore /usr/j2se/jre/lib/security/cacerts -alias VerisignTestCA -file testrootca.cer -noprompt -trustcacerts -storepass myStorePassword
An alternative (and recommended) option is to install the root certificate into the alternative system certificate file, jssecacerts:
keytool -import -keystore /usr/j2se/jre/lib/security/jssecacerts -alias VerisignTestCA -file testrootca.cer -noprompt -trustcacerts -storepass myStorePassword
A third possibility is to install the root certificate into some other key store file and configure the client to use that as its trust store. The following example installs into the file /home/smith/.keystore:
keytool -import -keystore /home/smith/.keystore -alias VerisignTestCA -file testrootca.cer -noprompt -trustcacerts -storepass myStorePassword
Since the client does not search this key store by default, you must explicitly provide its location to the client to use as a trust store. You do this by setting the Java system property javax.net.ssl.trustStore once the client is running: