is it possible if I have identical raspberry pi's external hdd's and sd card 's
Basically yes, although some network configuration will always be unique, such as IP and MAC addresses, and SSH keys.
I would like to update just one Pi then backup the file and restore it on other raspberry pi's.
How often are you planning to "update" a Raspberry Pi? If you are referring to Kodi's video and/or music library, the use of a centralized MySQL/MariaDB would be a much better solution.
All the external hdd's are labeled the same.
That is often not a very good idea, at Linux likes to tell the different disks apart. Having identical disk labels could confuse the Linux OS or Kodi.
Basically yes, although some network configuration will always be unique, such as IP and MAC addresses, and SSH keys.
How often are you planning to "update" a Raspberry Pi? If you are referring to Kodi's video and/or music library, the use of a centralized MySQL/MariaDB would be a much better solution.
That is often not a very good idea, at Linux likes to tell the different disks apart. Having identical disk labels could confuse the Linux OS or Kodi.
Klojum Duly Noted
I was referring to library updates.
