ISP2(config)#ip http server 
ISP2(config)#crypto pki server PKI_SERVER
ISP2(cs-server)#grant auto 
%PKI-6-CS_GRANT_AUTO: All enrollment requests will be automatically granted.t
ISP2(cs-server)#no shut
%Some server settings cannot be changed after CA certificate generation.
% Please enter a passphrase to protect the private key
% or type Return to exit
Password: P@ssw0rd

Re-enter password:P@ssw0rd 
% Generating 1024 bit RSA keys, keys will be non-exportable...
[OK] (elapsed time was 2 seconds)

%SSH-5-ENABLED: SSH 1.99 has been enabled
% Certificate Server enabled.
%PKI-6-CS_ENABLED: Certificate server now enabled.

ip http server
crypto pki server PKI_SERVER
 grant auto
 no shut
Password: P@ssw0rd
Re-enter password: P@ssw0rd

​ISP2#show crypto pki server 
Certificate Server PKI_SERVER:
    Status: enabled
    State: enabled
    Server's configuration is locked  (enter "shut" to unlock it)
    Issuer name: CN=PKI_SERVER
    CA cert fingerprint: 9D44063E 0B8B19AF 40043472 B4CF587C 
    Granting mode is: auto
    Last certificate issued serial number (hex): 1
    CA certificate expiration timer: 00:22:49 UTC Sep 15 2022
    CRL NextUpdate timer: 06:22:50 UTC Sep 16 2019
    Current primary storage dir: nvram:
    Database Level: Minimum - no cert data written to storage