I have one server, which I did not use for one month, literally shut down.
The server is running Debian 9.0. I upgraded it from Jessie about two months ago to testing repository.
Yesterday I needed it, so I turned it on and upgraded all packages for security reasons.
Before this upgrade: GRUB booted automatically the only OS on this server.
After this upgrade: I must press Enter for it to do so. Therefore I must have keyboard plugged in etc. I am sure you understand the inconvenience.
Also I noticed changed background both on the login screen, and the desktop.
As far as I know, this file:
/etc/default/grub
is responsible for GRUB's behavior, so I copy-paste it first:
# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
# info -f grub -n 'Simple configuration'
GRUB_DEFAULT=0
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet"
GRUB_CMDLINE_LINUX=""
# Uncomment to enable BadRAM filtering, modify to suit your needs
# This works with Linux (no patch required) and with any kernel that obtains
# the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...)
#GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef"
# Uncomment to disable graphical terminal (grub-pc only)
#GRUB_TERMINAL=console
# The resolution used on graphical terminal
# note that you can use only modes which your graphic card supports via VBE
# you can see them in real GRUB with the command `vbeinfo'
#GRUB_GFXMODE=640x480
# Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux
#GRUB_DISABLE_LINUX_UUID=true
# Uncomment to disable generation of recovery mode menu entries
#GRUB_DISABLE_RECOVERY="true"
# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE="480 440 1"
I did not do any other change. I am unsure whether it upgraded from Stretch to Sid or whatever the naming is. I am also confused as to what could cause this kind of seemingly negligible problem, but I sincerely hope there are folks who understand Debian better than me.
If you need any information I will deliver it on a timely fashion.
EDIT1:
uname -a
output
Linux backup-server 4.9.0-1-amd64 #1 SMP Debian 4.9.2-2 (2017-01-12) x86_64 GNU/Linux
and
cat /etc/apt/sources.list
output
deb http://ftp.sh.cvut.cz/debian/ testing main contrib non-free
deb-src http://ftp.sh.cvut.cz/debian/ testing main contrib non-free
deb http://security.debian.org/ testing/updates main contrib non-free
deb-src http://security.debian.org/ testing/updates main contrib non-free
