if you would like to backup or restore configuration and Firmware upgrade, you need to prepare for below step
step-1 you need to prepare for FTP server at you pc. below link for configure ftp server with Filezilla
https://www.youtube.com/watch?v=U0J2F7qrpts
sometimes, if your pc is join AD or under organization PC's, you need to allow firewall on your PC
step2- you need to configure repository on ISE GUI, as below for guide
https://www.cisco.com/c/en/us/support/docs/security/identity-services-engine-software/215348-how-to-configure-repository-on-identity.html
step3- GUI backup and restore
https://content.cisco.com/chapter.sjs?uri=/searchable/chapter/content/en/us/td/docs/security/ise/2-6/admin_guide/b_ise_admin_guide_26/b_ise_admin_guide_26_chapter_01100.html.xml#:~:text=Procedure,-Step%201&text=Choose%20Administration%20%3E%20System%....
Hopefully, help for guys.
Thank you.
