I have written system.conf file

{{{
abhishek@abhishek-Latitude-5490:~$ cat system.conf
[system]
compatible=eximius
bootloader=uboot
mountprefix=/mnt/rauc
statusfile=/factory/rauc.status

[keyring]
path=cert.pem

[slot.rescue.0]
#device=/dev/mmcblk1p0
device=/dev/disk/by-path/platform-219c000.usdhc-part0
type=raw
bootname=rescue

[slot.factory.0]
#device=/dev/mmcblk1p1
device=/dev/disk/by-path/platform-219c000.usdhc-part1
type=ext4
bootname=factory

[slot.servicewatch_datalogger.0]
#device=/dev/mmcblk1p2
device=/dev/disk/by-path/platform-219c000.usdhc-part2
type=ext4
bootname=servicewatch_datalogger

[slot.datalogger_space.0]
#device=/dev/mmcblk1p3
device=/dev/disk/by-path/platform-219c000.usdhc-part3
type=ext4
bootname=datalogger_space

[slot.rootfs.0]
#device=/dev/mmcblk1p4
device=/dev/disk/by-path/platform-219c000.usdhc-part4
type=ext4
bootname=A

[slot.rootfs.1]
#device=/dev/mmcblk1p5
device=/dev/disk/by-path/platform-219c000.usdhc-part5
type=ext4
bootname=B

[slot.appfs.0]
#device=/dev/mmcblk1p6
device=/dev/disk/by-path/platform-219c000.usdhc-part6
type=ext4
parent=rootfs.0

[slot.appfs.1]
#device=/dev/mmcblk1p7
device=/dev/disk/by-path/platform-219c000.usdhc-part7
type=ext4
parent=rootfs.1

[slot.appdata.0]
#device=/dev/mmcblk1p8
device=/dev/disk/by-path/platform-219c000.usdhc-part8
type=ext4
parent=rootfs.0

[slot.appdata.1]
#device=/dev/mmcblk1p9
device=/dev/disk/by-path/platform-219c000.usdhc-part9
type=ext4
parent=rootfs.1
}}}

how to use hook in order to preserve the data of appdata0, while installing bundle .

In which file i have to give hook option?

Regards,

Abhishek