Upgrade
Yocto
TODO
Debian
The apt package tool is used to upgrade the system. You can use the rollback to avoid loss the system (more details in the below section).
apt update apt upgrade
Rollback
As mentioned here, the root partition is in LVM disk. With this configuration, it can be save by a LVM snapshot.
lvcreate -L SIZE -s -n SNAPSHOT_NAME /dev/VOLUME_GROUP/DISK_NAME
With snapshots, the partition can be rollback in the stable state with this command:
lvconvert --merge /dev/VOLUME_GROUP/SNAPSHOT_NAME
Otherwise, the snapshot can be remove with these commands:
lvremove /dev/VOLUME_GROUP/SNAPSHOT_NAME
More details here.
Troubleshooting
Can't create a snapshot with old name
If you don't resboot the machine, the lvcreate command believes the name is always used. To remove it, you need to launch this command:
vgchange --refresh