readme mtls part update

Signed-off-by: barakda <[email protected]>

README.md

@@ -255,10 +255,10 @@ echo $NVMEOF_VERSION...
 
 For testing purposes, self signed certificates and keys can be generated locally using OpenSSL.
 
-For the server, generate credentials for server name 'my.server' in files called server.key and server.crt:
+For the server, generate credentials for the server named 'my.server' and save them in files called server.key and server.crt. Additionally, specify subject alternative names using the gateway group nodes' IPs in the openssl command.
 
 ```bash
-$ openssl req -x509 -newkey rsa:4096 -nodes -keyout server.key -out server.crt -days 3650 -subj '/CN=my.server'
+$ openssl req -x509 -newkey rsa:4096 -nodes -keyout server.key -out server.crt -days 3650 -subj '/CN=my.server' -addext "subjectAltName=IP:192.168.13.3,IP:192.168.13.4,IP:192.168.13.5,IP:192.168.13.6"
 ```
 
 For client: