Java KeyStore usage and Commands

Java Keytool is a key and certificate management utility. It allows users to manage their own public/private key pairs and certificates. It also allows users to cache certificates. Java Keytool stores the keys and certificates in what is called a keystore. By default the Java keystore is implemented as a file. It protects private keys with a password. A Keytool keystore contains the private key and any certificates necessary to complete a chain of trust and establish the trustworthiness of the primary certificate.

Each certificate in a Java keystore is associated with a unique alias. When creating a Java keystore you will first create the .jks file that will initially only contain the private key. You will then generate a CSR and have a certificate generated from it. Then you will import the certificate to the keystore including any root certificates. Java Keytool also several other functions that allow you to view the details of a certificate or list the certificates contained in a keystore or export a certificate.

Note: For easier management of your Java Keystores (using a GUI) check out Portecle. If you need to buy a certificate, try to compare SSL with our SSL Wizard.

Compare SSL Certificates

Below, we have listed the most common Java Keytool keystore commands and their usage:

Java Keytool Commands for Creating and Importing

These commands allow you to generate a new Java Keytool keystore file, create a CSR, and import certificates. Any root or intermediate certificates will need to be imported before importing the primary certificate for your domain.

• Generate a Java keystore and key pair

keytool -genkey -alias mydomain -keyalg RSA -keystore keystore.jks -keysize 2048

• Generate a certificate signing request (CSR) for an existing Java keystore

keytool -certreq -alias mydomain -keystore keystore.jks -file mydomain.csr

• Import a root or intermediate CA certificate to an existing Java keystore

keytool -import -trustcacerts -alias root -file Thawte.crt -keystore keystore.jks

• Import a signed primary certificate to an existing Java keystore

keytool -import -trustcacerts -alias mydomain -file mydomain.crt -keystore keystore.jks

• Generate a keystore and self-signed certificate (see How to Create a Self Signed Certificate using Java Keytool for more info)

keytool -genkey -keyalg RSA -alias selfsigned -keystore keystore.jks -storepass password -validity 360 -keysize 2048

Java Keytool Commands for Checking:

If you need to check the information within a certificate, or Java keystore, use these commands.

• Check a stand-alone certificate

keytool -printcert -v -file mydomain.crt

• Check which certificates are in a Java keystore

keytool -list -v -keystore keystore.jks

• Check a particular keystore entry using an alias

keytool -list -v -keystore keystore.jks -alias mydomain

Other Java Keytool Commands

• Delete a certificate from a Java Keytool keystore

keytool -delete -alias mydomain -keystore keystore.jks

• Change a Java keystore password

keytool -storepasswd -new new_storepass -keystore keystore.jks

• Export a certificate from a keystore

keytool -export -alias mydomain -file mydomain.crt -keystore keystore.jks

• List Trusted CA Certs

keytool -list -v -keystore $JAVA_HOME/jre/lib/security/cacerts

• Import New CA into Trusted Certs

keytool -import -trustcacerts -file /path/to/ca/ca.pem -alias CA_ALIAS -keystore $JAVA_HOME/jre/lib/security/cacerts