Grub Troubleshooting

Troubleshooting Linux on the Desktop Don Vosburg Linux Technology Specialist Novell, Inc [email protected]

March 24, 2006

Session Road Map

2

•

Rethink your desktop troubleshooting

•

Installation/Deployment

•

Graphical interface problems

•

Common Application issues

•

Network integration

•

Upgrading and patching

•

Printing

•

Where to find help

•

Questions and answers

© Novell, Inc.

Basic Assumptions •

•

Model for this session: Novell Linux Desktop ®

–

SUSE principles carry over – YaST, SuSEConfig, etc

–

May have application to other distro's – but that kind of adaptation is up to you

–

Will take into consideration NLD9 and SUSE Linux Enterprise Desktop 10

3

®

Comfort with Linux command line –

•

®

GUI is great for users – but CLI is essential for resolving issues

Establish your own best practices –

Baseline to know when something is REALLY wrong

–

Preclude issues before handing the desktop off to end users

© Novell, Inc.

From Community to Enterprise

openSUSE feeds the enterprise Linux offerings

Various open source projects Rapidly growing in number of projects and their capabilities Isolated, uncoordinated efforts

4

© Novell, Inc.

Linux for enthusiasts and individual end users Technical previews and leading edge applications

Hardened, Secure, Supported Certified for leading hardware and software platforms 7-year code maintenance guarantee

Novell Linux Desktop 9 ®

Designed specifically to empower businesses to leverage Linux and open source with confidence •

Reliable, secure and manageable desktop for costeffective deployments •

Can be tailored for use in information kiosks, call-center terminals, or stations •

Usable as a general purpose desktop for infrequent PC users •

Exercise patience!

•

5

© Novell, Inc.

Rethink Desktop Troubleshooting •

•

•

Rebooting does NOT cure all ills –

Only likely to restart the problem

–

Sometimes makes it worse!

Know the symptoms –

Break things

–

Experience it for yourself

Get the right tools –

From Windows: putty, vncviewer, WinSCP

–

From Linux: ssh, vncviewer, konqueror

–

YaST is your best friend

–

Make friends with an expert

• 6

© Novell, Inc.

Installation and Deployment •

•

Installation – complicated and sometimes troublesome –

4-5 CD's, including service packs

–

What packages do I really need?

–

Partitioning the disk

Create a network installation point –

•

7

Can be scripted to include service-packs as a single install

Use AutoYaST to “script” installations –

XML file to answer the installation questions for you

–

Start with an installed system as a template

© Novell, Inc.

Deployment Issues •

Imaging programs –

–

–

8

Practice using the imaging programs available to you >

ZEN imaging – need ZLM7

>

Ghost – v8 or above

Open Source options >

g4l, g4u – thorough but slow

>

partimage – fast but requires intervention, manual partitioning

>

Clonezilla – nice server-based wrapper for partimage

Filesystem choices affect your success >

reiserfs (the NLD default) needs to be supported

>

avoid over-complication (EVMS, LVM, over-partitioning)

© Novell, Inc.

What If It Won't Boot? •

Stuck at the GRUB prompt –

Usually means problems in grub or /etc/fstab

–

NLD 9 does not have the YaST repair tools

–

>

But – shares code with SLES9/OES

>

Use OES Linux CD1 to run the YaST repair tool

Beware the device assignment >

SATA controllers – supported with NLD9 SP2+

>

SATA drives are hda, hdb, hdc, hdd

>

IDE controllers are enumerated AFTER SATA if SATA is present – »

–

Know where grub files are stored >

• 9

hde, hdf, hdg, hdh

© Novell, Inc.

/boot/grub and /etc/grub.conf

Rethinking – Root is “superuser”

10

•

“Normal” linux users do not have all power

•

Keep root password secure

•

root user can inadvertently cause problems –

file permissions

–

accidental deletions, relocations

•

Avoid logging into the GUI as root

•

root's home directory kept separate

•

Know how to use su –

kdesu, gnomesu

–

sudo

© Novell, Inc.

Recovering Lost Root Password •

Requires access to local console

•

Interrupt the boot process

•

Select Failsafe, and delete all listed options

•

Type init=/bin/bash on the Boot line

•

Remount the root partition to be read/write –

•

Change the root password –

•

# passwd root

Restart the system –

11

# mount -n -o rw,remount /

3-fingered salute - CTL-ALT-DEL

© Novell, Inc.

GUI issues •

•

Remember – the GUI is not the operating system –

This is one reason knowing the CLI is critical

–

Simple text configuration files can be edited, replaced to solve problems

Know the elements of the GUI –

Display manager – gdm, kdm

–

X Configuration – sax2

•

Hidden files - .gnome, .gnome2, .gconf, .kde

•

Display manager –

• 12

Which one and what starts it?

Panels and menus

© Novell, Inc.

If the GUI fails to load....

13

•

All is not lost – use the command line

•

CTL-ALT-F1, F2, etc

•

Try loading the alternate GUI session

•

Try a different user account

•

Example: A common gnome issue: –

esd – sound server can prevent gnome from starting

–

Kill process and disable server in control center until issues are resolved

•

Know how to switch runlevels – init 3, init 5

•

Learn sax2 switches – sax2 -r -m 0=vesa

© Novell, Inc.

Common Application issues •

Install applications from appropriate rpm files! –

Distribution files first

–

rpm files known to be built from your distro

–

Use Red Carpet/ZLM client

•

I know I installed it – where did it go?

•

Use /etc/skel –

Settings passed on to new users

•

OpenOffice: file formats, font choices

•

Firefox: plugins/extensions, themes

•

Hidden files –

.ooo-org1-1, .ooo-org2, .mozilla, etc

• 14

© Novell, Inc.

Network integration •

How do network interfaces work? –

/etc/sysconfig/network

–

yast lan

–

NetworkManager in Code 10 desktop

•

Linux in a Windows World - samba

•

Connecting to a Novell-server (NCP) network –

15

Use the Novell Client for Windows

•

“mapped” connections

•

Beware security risk of storing clear-text authentication

© Novell, Inc.

Upgrading and patching •

Use Red Carpet/ZENworks Linux Management client ®

–

•

Always test first –

•

Prevents inadvertent updating/breaking

Manage the process –

16

Not all RPM's are created equal

Lock the applications you customize –

•

Discipline results in clean RPM database

Use your own ZLM server – SO COOL!

© Novell, Inc.

Printing and Linux desktop •

•

17

Local print “server” –

CUPS – rights to CUPS can break

–

filtering – printer definitions

Centralize when you can –

iPrint – beware the “high security” default

–

LPR/LPD

–

Samba/Windows server print shares

•

Set default printer

•

Use supported printers, or get access to PPD files

© Novell, Inc.

Where to find help •

Novell CoolSolutions ®

–

•

Package search site: –

•

http://support.novell.com/forums/2nld.html

NLD deployment guide –

18

http://rpm.pbone.net

Forums at Novell –

•

http://www.novell.com/coolsolutions/nld/

http://www.novell.com/documentation/nld/pdfdoc/nld_deploym ent/nld_deployment.pdf

© Novell, Inc.

Questions & Answers

Unpublished Work of Novell, Inc. All Rights Reserved. This work is an unpublished work and contains confidential, proprietary, and trade secret information of Novell, Inc. Access to this work is restricted to Novell employees who have a need to know to perform tasks within the scope of their assignments. No part of this work may be practiced, performed, copied, distributed, revised, modified, translated, abridged, condensed, expanded, collected, or adapted without the prior written consent of Novell, Inc. Any use or exploitation of this work without authorization could subject the perpetrator to criminal and civil liability. General Disclaimer This document is not to be construed as a promise by any participating company to develop, deliver, or market a product. Novell, Inc., makes no representations or warranties with respect to the contents of this document, and specifically disclaims any express or implied warranties of merchantability or fitness for any particular purpose. Further, Novell, Inc., reserves the right to revise this document and to make changes to its content, at any time, without obligation to notify any person or entity of such revisions or changes. All Novell marks referenced in this presentation are trademarks or registered trademarks of Novell, Inc. in the United States and other countries. All third-party trademarks are the property of their respective owners.