Troubleshooting your Live CD

From The Linux Mint Wiki

Contents 1 Troubleshooting your Live CD 2 Downloading 3 Burn your CD 4 Options in Elyssa 5 Motherboard problems 6 When you install 7 Problems with the video card and its drivers 8 This helps "X problems" in installed systems as well 8.1 Solving some "out of range" problems 9 Installing from the Live CD 10 No internet connection for envy? 11 Before you install please read "How_to_partition"

Troubleshooting your Live CD

Introduction
This troubleshooter is partly outdated, but still a valuable resource for troubleshooting. It was originally written to solve the non working "Safe graphics mode" in Bianca. From Cassandra "Safe graphics mode" works as intended
It's so much used in support that it is locked from editing to avoid that it is destroyed.
Unfortunately we even had the entire howto section of the wiki destroyed once and parts of it several times.
If you want to contribute please do so in the discussion tab and if it is good I will include it in the main article /husse
The section about internet connection is still highly useful
The section about troubleshooting motherboard problems will be increased and research is going on. It's not easy though to find good and reliable solutions.

Downloading

There is one seriously important point here - Check the md5sum. Do it always. As the ISO is a large file take some care not to do something that might interrupt/corrupt the download. It is correct that a torrent client checks the md5, but the effort to check is so small that I still recommend to do it. And if the source for the torrent is not absolutely well reputable this is a must. In Linux there is a md5sum checker by default (it's a CLI tool), but for Windows you have to download and install some third party software. One of the best for Windows is Nullriver WinMD5Sum (http://www.nullriver.com/products)

Burn your CD

There is an article on this subject now in the howto section Burning_ISO
Make sure you are not burning a copy of the ISO but a bootable CD. It might be a bit tricky to find the right menu entry for this. E.g. in Nero 5 it is under "Archive>Burn image".
Before booting with your new CD make sure that CD is first in the boot sequence of your computer. If your computer ignores the live CD you have not done that.
I received some links to free CD/DVD burners for Windows, in case you don't use the program that came with the burner.
Ashampoo: http://www2.ashampoo.com/webcache/html/1/product_2_1110__.htm, commercial and requires registering, but free of charge. And InfraRecorder: http://infrarecorder.sourceforge.net/ which is totally free :)
That's basic, now to the real problems

Options in Elyssa

Elyssa has a new splash for the live CD - press any key to see the options.
All below works but if you use the solution to get rescue mode from the live CD/DVD you are met with a box asking you what your intention is after a while. No problem to understand that, but it's worth mentioning

Motherboard problems

These are hard to diagnose and solve.
There are many different solutions and these are just the most important ones.

Press F6 when you see the splash for the live CD and delete "quiet splash --" and type in various options which will be given below.

Try any of the following or any combination of them

noapic
nolapic
noacpi 
acpi=off 
pci=noacpi 
nopcmcia  #only if you have pcmcia 
irqpoll 
all_generic_ide 

You can also try to disable the floppy in BIOS

There are more to try but it is hard to find all the possible alternatives
You can also control resolution during boot with the parameter vga= according to the table below
You add it with F6 like the ones above

1. VESA framebuffer console @ 1024x768x64k
   
2. vga=791
   
3. VESA framebuffer console @ 1024x768x32k
   
4. vga=790
   
5. VESA framebuffer console @ 800x600x32k
   
6. vga=787
   

Furthermore sometimes if you have SATA discs and mostly an older motherboard this helps

1. Add the following option to the beginning of the options list:
   
2. break=top or break=bottom or break=button - one of them should do it.
   

A better solution is to remove "quiet splash --" and add "ro single" (no quotes) which will take you to "Recovery mode"
Mint will start booting, but kick you out to a command prompt; at the prompt type these two commands:

modprobe piix

exit

If that works you will now boot into the LiveCD.

When you install

If you had to add anything of the above to boot the live CD chances are that this must be done in the installed version too.
When the install is ready, continue using the live CD and edit a bit before you reboot.
In the installed Mint edit /boot/grub/menu.lst
For gnome gksudo gedit /dev/sdx /boot/grub/menu.lst
For KDE kdesu kate /dev/sdx /boot/grub/menu.lst
Where x is your number of course
In the lines that boots Mint add the option you used above. The lines look like this originally (of course you probably don't have sda7)
kernel /boot/vmlinuz-2.6.20-15-generic root=/dev/sda7 ro quiet splash
Remove or keep "quiet splash" according to what you found out is necessary and add your options after "ro"
You can't do this for the modprobe piix alternative obviously (as it will be done for the live CD not the installed version)
You can probably boot into recovery mode and do as above - type these two commands:

modprobe piix

exit

There is a way to pass options like these during normal boot. It is not persistent though
Once the GRUB boot loader has successfully started you will see the main menu screen with a list of menu titles.

Do the following:

1. press 'e' to edit a given menu title
2. scroll down to the line containing 'kernel' and press 'e' again
3. you can add any options here
4. to boot with the current options type 'b'. Otherwise just press return to get the unaltered line back

Notice that pressing the ESC key will bring you back to a previous stage. You can navigate back to the main menu this way.

This section is a bit thin, it's not easy to gather the information needed to make it "thicker". In the forum [1] you may find more solutions - unfortunately the posts are a bit "scattered".

Problems with the video card and its drivers

The boot process goes on for a while, you may see some garbled image on your screen and then the boot stops. This is due to the Xserver not being started.

The reason for this can be that the Live CD is using the wrong graphics drivers. When the live CD starts up press F6 and delete the "quiet splash --" ending. Recently (march 2008) it was discovered that you can boot into recovery mode with the live cd. To do that, add "ro single" (no quotes) where you just deleted "quiet splash --"

This will get rid of the Mint splash screen and stop half way through booting with a command prompt.

This helps "X problems" in installed systems as well

If your installed Mint can't start X, reboot into "Recovery Mode" and follow the procedure below.

When you get to the prompt type in the following:

nano /etc/X11/xorg.conf Note: there has to be a space between between nano and /etc. Please note that the X in X11 must be a major X

This will let you edit your graphics configuration file. Using the arrow keys scroll down to the heading called "Device". Under this it should have "Driver" to the left and beside it the driver in inverted commas, like so:

   Section "Device"
   Identifier     "NVIDIA Corporation NV43 [GeForce 6600 GT]"
   Driver         "nv"
   EndSection

It's the same for ATI as for nVidia, only when it is an ATI card the Driver is (probably) "ati".

Change whatever is identified as driver to "vesa" (one set of quotes) Once you've done this press Ctrl+x then y then enter to exit the text editor

This will bring you back to the command line, simply type:

exit

and, fingers crossed, Mint should boot.
Never, ever, use startx here as you are root and will continue to be so

The vesa driver is a savior but gives really sloppy graphics. So when the desktop emerges you will see quite well how it looks, but as soon as you try to do something you will notice considerable problems (in scrolling and more). These will NOT be there with the correct driver.

Solving some "out of range" problems

You may get an error message that your monitor is out of range. This seems to happen with some wide screen monitors.
The first thing to do is to boot into "Recovery mode" as described above.
Now you should have the manual for your monitor handy. Edit xorg.conf as described above only this time you edit Section "Monitor".
It's the horizontal and vertical refresh values you fill in (Horizsync and Vertrefresh)
If no values exist add them. It should look something like this

Section "Monitor"

Identifier "Generic Monitor" Option "DPMS" Horizsync 30-70 Vertrefresh 50-160

EndSection

Save the file and as above exit with exit.
Sometimes this does not even help.
The solution below should be used only if nothing else works!
Use Envy to install drivers for ATI or nvidia and you may be able to boot the live CD. To do this you must have an internet connection and not all hardware allows that.
You will of course have to install again in the installed version....
Run envy -t and follow the prompts
At the Envy menu DON'T reboot, choose Restart X Server
Unfortunately this makes you root and about the last thing you should do is run as root.
Just wait for the desktop to be fully loaded, then open the menu and click quit.
Then "Log out" - you are in pure CLI. For Gnome use gdm and for KDE use kdm and you will be a normal user.
There is no install icon unless you do that.
Check that the xorg.conf file in the installed version has the correct refresh rates before you reboot.
For gnome gksudo gedit /dev/sdx /etc/X11/xorg.conf
For KDE kdesu kate /dev/sdx /etc/X11/xorg.conf
where of course sdx is the partition you installed to

Installing from the Live CD

It's no good idea to install the correct drivers until you have installed Mint since, obviously, all changes disappear when you turn off/reboot - unless you try to solve a problem.
The next step is to install and there is an icon on the desktop suitably named "Install Mint".
When you do that "vesa" is choosen as the video driver if you used "Safe graphics mode" to boot the live CD/DVD.
Recently (march 2008) it was discovered that in some cases the "vesa" driver is not "inherited" to the installed version, which forces you to repeat this action with the installed version. This is a bug and will hopefully be fixed.
Once you see the desktop again you better install the correct driver immediately as "vesa" is hopeless other than as a last resort.
Check that you have internet connection, open a terminal and give the command " sudo envy". Envy is included in Mint, and perhaps better started from the menu.
(The latest version does not require stopping Xserver any more.)
You can find envy here http://albertomilone.com/nvidia_scripts1.html
Envy installs automagically the video drivers for nVidia and ATI. Just follow the instructions and soon you have the latest driver installed.

Now you have a nice Mint to taste.

Be sure that you let the installation program configure your Xserver (xorg.conf) or you will still have "vesa". You can easily change that by hand, but it's better to let the installer take care of it.

No internet connection for envy?

This section is a general problem solver not only for the live CD. If you use the live CD skip step 2, as that's irrelevant in that case. This solution even works for Debian.

You may experience that you do not have an internet connection for envy, apt-get and Synaptic, but that you can use Firefox or the other way round.
Broadband routers tell your system to use the router as DNS server when it gives you a DHCP lease - DNS forwarding. This does sometimes not work for all applications - they have to be told that there's a DNS server on the internet.
Luckily, there is a fairly simple solution.
You may find that you can set an address to a DNS server in network.config in "Networking" in the Control center. This setting is not sticky and disappears from time to time. This is because the /etc/resolv.conf is reset to the IP of your router (something like 192.168.1.1) at every DHCP lease (and reboot).

Step 1)
For gnome gksudo gedit /etc/resolv.conf
For kde kdesu kate /etc/resolv.conf
add the IP of the DNS server(s) of your ISP if you know them or to OpenDNS (208.67.222.222 and 208.67.220.220).
Add "nameserver 208.67.222.222" (no quotes), one line per server, a maximum of 3 servers.
There should already be a line with a nameserver IP there. Use it as a pattern, and place it as the last line.

Without step 2 this is useless if you want the DNS servers to be "sticky" after reboot, but is of course not useful for the live CD.

Step 2)
For gnome gksudo gedit /etc/dhcp3/dhclient.conf
For KDE kdesu kate /etc/dhcp3/dhclient.conf

Add a line "prepend domain-name-servers 208.67.222.222,208.67.220.220;" (no quotes)
It seems that you should place the line directly before the first uncommented line, beginning with "request subnet-mask".
The DNS servers here must be the same as in /etc/resolv.conf.

The prepend stops the servers being ditched in etc/resolv.conf when the router makes a DHCP release.

If you know the IP of your ISP's DNS server use that instead of OpenDNS!

Before you install please read "How_to_partition"

This gives you some hints to partition "the right way"