Generate certificates

[Aayush_Agrawal]

Trying to generate certificates using below command
bin/elasticsearch-certutil ca --pem
Getting below error
Exception in thread "main" java.lang.IllegalArgumentException: Could not resolve placeholder 'FQDN'
at org.elasticsearch.common.settings.PropertyPlaceholder.parseStringValue(PropertyPlaceholder.java:116)
at org.elasticsearch.common.settings.PropertyPlaceholder.replacePlaceholders(PropertyPlaceholder.java:69)
at org.elasticsearch.common.settings.Settings$Builder.replacePropertyPlaceholders(Settings.java:1198)
at org.elasticsearch.common.settings.Settings$Builder.replacePropertyPlaceholders(Settings.java:1160)
at org.elasticsearch.node.InternalSettingsPreparer.initializeSettings(InternalSettingsPreparer.java:128)
at org.elasticsearch.node.InternalSettingsPreparer.prepareEnvironment(InternalSettingsPreparer.java:107)
at org.elasticsearch.cli.EnvironmentAwareCommand.createEnv(EnvironmentAwareCommand.java:95)
at org.elasticsearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:86)
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:124)
at org.elasticsearch.cli.MultiCommand.execute(MultiCommand.java:77)
at org.elasticsearch.cli.Command.mainWithoutErrorHandling(Command.java:124)
at org.elasticsearch.cli.Command.main(Command.java:90)
at org.elasticsearch.xpack.security.cli.CertificateTool.main(CertificateTool.java:137)