As an another countermeasure against security threats I wrote a little script that computes MBR and boot checksum and then compare it to the old one. As long as the computer is running this is OK, but when I restart it, the checksum is changed.QUESTION -- what is the cause of changing and how to prevent it?Details: openSUSE 13.2, noatime for /boot set, boot parition is a separate partition (it is not just a directory in root filesystem), the partition is unmounted right after I log in and it is the first step before the computation of the checsum.The script:#!/bin/shsudo umount /boot# MBRsudo dd if=/dev/sda bs=512 status=noxfer count=1 | sha1sum | diff bootcheck_mbr.sha1 -MBR_RES=$?# boot partitionsudo dd if=/dev/sda1 bs=1M status=noxfer | sha1sum | diff bootcheck_boot.sha1 -BOOT_RES=$?if [[ $MBR_RES -ne 0 ]] || [[ $BOOT_RES -ne 0 ]]then  kdialog --sorry WARNING:\nBoot disk is changed. --title BOOT CHECK --geometry 0x0++300+400else  kdialog --title Boot check --passivepopup The disk is unchanged. 25 --geometry 0x0++300+400fi
What changes my boot partition and how to prevent it?
boot;security;checksum