On the dialog of grub setting, I just typed Enter with the default selection of hdd choice.
And, it failed to boot after the dist upgrade and went into its rescue mode.
I googled but couldn't find an exact same case, but it's... grub. Yes, GRUB. ... 2 actually.
I have RAID0 (mirroring) arrayed by mdadm with two of 500GB WD hard drives. So I did it with sdb too.
$ sudo grub-install /dev/sda
$ sudo grub-install /dev/sdb
$ sudo update-grub
Reboot, and problem solved.
Apache2 couldn't run itself after the upgrade.
$ sudo service apache2 status
So it was not running.
$ sudo service apache2 start
It showed me some error msg about the reason, but definitely it's caused by the upgrade. Yes, I chose 'Keep current settings' when the new apache2 installation process asked me what to do.
$ cd /etc/apache2
$ mv apache2.conf apache2.conf.old
apache2.conf is my old setting and wasn't compatible perfectly to run new apache2. Of course there was a kind skeleton file for that, 'apache2.conf.dpkg-dist'.
$ mv apache2.conf.dpkg-dist apache2.conf
$ sudo vi apache2.conf
Include /etc/phpmyadmin/apache.conf
ServerName www.mywebsite.com
When I started apache2 service again, it worked the same as before.
