Hello
Few days ago i needed SSL Certificate with SAN
Tryied few conbinations, and found this:

Create keystore file

keytool -genkey -alias <your alias> -keyalg RSA -keysize 2048 -sigalg SHA256withRSA -keystore server.keystore -ext san=dns:<your alias>

If you use your own password other than the default [that is, 'accounts' in this case] then, you need to update the [own] password in the following files:
../conf/server.xm;
../accounts/conf/server.xml
../reports/conf/server.xml

Create CSR file

keytool -certreq -alias <your alias> -sigalg SHA256withRSA -file server.csr -keystore server.keystore  -ext san=dns:<your alias>

Next steps you can find here: https://support.zoho.com/portal/manageengine/kb/articles/creating-new-ssl-certificate

Regards
Lukasz

Regards
Lukas