1. Certificate management

[root@k8s-master ~]# openssl genrsa -des3 -passout pass:x -out dashboard.pass.key 2048
Generating RSA private key, 2048 bit long modulus
.............................................+++
.+++
e is 65537 (0x10001)
[root@k8s-master ~]#
[root@k8s-master ~]#
[root@k8s-master ~]# openssl rsa -passin pass:x -in dashboard.pass.key -out dashboard.key
writing RSA key
[root@k8s-master ~]# rm dashboard.pass.key
rm: remove regular file 'dashboard.pass.key'? y
[root@k8s-master ~]#
[root@k8s-master ~]#
[root@k8s-master ~]# ls
anaconda-ks.cfg  cluster_initialized.txt  dashboard.key  original-ks.cfg
[root@k8s-master ~]#
[root@k8s-master ~]#
[root@k8s-master ~]# openssl req -new -key dashboard.key -out dashboard.csr
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
-----
Country Name (2 letter code) [XX]:kr
State or Province Name (full name) []:oppo
Locality Name (eg, city) [Default City]:seoul
Organization Name (eg, company) [Default Company Ltd]:sanse
Organizational Unit Name (eg, section) []:devops
Common Name (eg, your name or your server's hostname) []:k8s-master.thesanse.com
Email Address []:sooabia22@sptek.co.kr

Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:
[root@k8s-master ~]#
[root@k8s-master ~]# openssl x509 -req -sha256 -days 365 -in dashboard.csr -signkey dashboard.key -out dashboard.crt
Signature ok
subject=/C=kr/ST=oppo/L=seoul/O=sanse/OU=devops/CN=k8s-master.thesanse.com/emailAddress=sooabia22@sptek.co.kr
Getting Private key
[root@k8s-master ~]#