Java Keytool commands

Java Keytool is a key and certificate management utility. It allows users to manage their own public/private key pairs and certificates. Java Keytool stores the keys and certificates in what is called a keystore.  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.

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

• 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

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

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

• 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