Archive for May, 2014

Ubuntu Grub2 Refresh Rate Problems

May 20th, 2014 No comments

I had to make a few changes to /etc/default/grub to get Ubuntu 14.04 to boot with a working console. Initially, my monitor just went dark.

Changes with reasons:

GRUB_HIDDEN_TIMEOUT: if you want to see the Grub menu, this must be commented out.

GRUB_CMDLINE_LINUX: allows passing parameters to the linux startup command. Newer kernels (>3.5? or so) reinitialize the graphics card. My AMD Radeon something-or-other didn’t like this at all. nomodeset forces linux to use/keep BIOS graphics settings.

GRUB_GFXMODE: select resolution for Grub graphical starup. 1280×1024 works on my aging ViewSonic. This setting is for the Grub menu.

GRUB_GFXPAYLOAD_LINUX: specifying keep, causes Grub to keep using the previous resolution (from GRUB_GFXMODE) for the rest of the boot. 

NB: after making any changes, remember to update-grub (or nothing will happen).

Contents of my /etc/default/grub after making required changes:

# 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_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
# 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 …)

# Uncomment to disable graphical terminal (grub-pc only)

# 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’

# Uncomment if you don’t want GRUB to pass “root=UUID=xxx” parameter to Linux

# Uncomment to disable generation of recovery mode menu entries

# Uncomment to get a beep at grub start
#GRUB_INIT_TUNE=”480 440 1″

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Disable IPv6 in Ubuntu 14.04 (and others)

May 19th, 2014 No comments

My ISP (ding, dong) is stupid, so I need to disable IPv6.

sudo vim /etc/sysctl.conf

Add these four lines:

# No IPv6
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1

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