<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <HTML> <HEAD> <META NAME="GENERATOR" CONTENT="SGML-Tools 1.0.9"> <TITLE>HOWTO: Multi Disk System Tuning: Troubleshooting </TITLE> <LINK HREF="Multi-Disk-HOWTO-16.html" REL=next> <LINK HREF="Multi-Disk-HOWTO-14.html" REL=previous> <LINK HREF="Multi-Disk-HOWTO.html#toc15" REL=contents> </HEAD> <BODY> <A HREF="Multi-Disk-HOWTO-16.html">Next</A> <A HREF="Multi-Disk-HOWTO-14.html">Previous</A> <A HREF="Multi-Disk-HOWTO.html#toc15">Contents</A> <HR> <H2><A NAME="troubleshooting"></A> <A NAME="s15">15. Troubleshooting </A></H2> <P> <!-- disk!troubleshooting --> Much can go wrong and this is the start of a growing list of symptoms, problems and solutions: <P> <P> <H2><A NAME="ss15.1">15.1 During Installation</A> </H2> <H3>Locating Disks</H3> <P> <DL> <DT><B>Symptoms</B><DD><P>Cannot find disk <DT><B>Problem</B><DD><P>How to find what drive letter corresponds to what disk/partition <DT><B>Solution</B><DD><P>Remember Linux does not use drive letters but device names. More information can be found in <A HREF="Multi-Disk-HOWTO-3.html#drive-names">Drive names</A>. </DL> <P> <DL> <DT><B>Symptoms</B><DD><P>Cannot partition disk <DT><B>Problem</B><DD><P>Most likely wrong input to the command line for <CODE>fdisk</CODE> or similar tool. <DT><B>Solution</B><DD><P>Remember to use <CODE>/dev/hda</CODE> rather than just <CODE>hda</CODE>. Also do not use numbers behind <CODE>hda</CODE>, those indicate partitions. </DL> <P> <P> <H3>Formatting</H3> <P> <DL> <DT><B>Symptoms</B><DD><P>Cannot format disk. <DT><B>Problem</B><DD><P>Strictly speaking you format partitions not disks. <DT><B>Solution</B><DD><P>Make sure you add the partition number after the device name of the disk, for instance <CODE>/dev/hda1</CODE> to the command line. </DL> <P> <P> <P> <H2><A NAME="ss15.2">15.2 During Booting</A> </H2> <H3>Booting fails</H3> <P> <DL> <DT><B>Symptoms</B><DD><P>Number keep scrolling up the screen. <DT><B>Problem</B><DD><P>Possibly corrupt disk. <DT><B>Solution</B><DD><P>Try another disk, you might have to reinstall. Check for loose cables and possible data corruption. </DL> <P> <DL> <DT><B>Symptoms </B><DD><P>Get <CODE>LI</CODE> and then it hangs. <DT><B>Problem</B><DD><P>You use LILO to load Linux but LILO cannot find your root. <DT><B>Solution</B><DD><P>Read the LILO HOWTO. </DL> <P> <DL> <DT><B>Symptoms</B><DD><P>Kernel panics, something about missing root file system. <DT><B>Problem</B><DD><P>The kernel does not know where the root partition is. <DT><B>Solution</B><DD><P>Use <CODE>rdev</CODE> or (if applicable) LILO to add information to the kernel image where your root is. </DL> <P> <P> <H3>Getting into Single User Mode</H3> <P> <DL> <DT><B>Symptoms</B><DD><P>System boots but get into a root shell in single user mode. <DT><B>Problem</B><DD><P>Something went wrong in the later stages of booting and the system has come far enough to let you open a shell to repair the system. <DT><B>Solution</B><DD><P>Locate the problems from the boot log. Note that file system can be in read-only mode. Remount read-write if you have to. Often the reason is that the <CODE>/etc/fstab</CODE> contained an entry that was mismapped such as trying to mount a swap partition as your normal file space. </DL> <P> <P> <H2><A NAME="ss15.3">15.3 During Running</A> </H2> <H3>Swap</H3> <P> <DL> <DT><B>Symptoms</B><DD><P>Short on memory <DT><B>Problem</B><DD><P>Swap space is not available <DT><B>Solution</B><DD><P>Type free and check the output. If you get <BLOCKQUOTE><CODE> <PRE> total used free shared buffers cached Mem: 46920 30136 16784 7480 11788 5764 -/+ buffers/cache: 12584 34336 Swap: 128484 9176 119308 </PRE> </CODE></BLOCKQUOTE> then system is running normal. If the line with <CODE>Swap:</CODE> contains zeros you have either not mounted the swap space (partition or swap file) (see <CODE>swapon(8)</CODE>) or not formatted the swap space (see <CODE>mkswap(8)</CODE>). </DL> <P> <P> <P> <H3>Partitions</H3> <P> <DL> <DT><B>Symptoms</B><DD><P>No room amidst plenty 1 <DT><B>Problem</B><DD><P>Partitionitis:Underdimensioned partition sizes has caused overflow in some areas <DT><B>Solution</B><DD><P>Examine your partition usage using <CODE>df(1)</CODE> and locate problem areas. Normally the problem can be solved by removing old junk but you might have to repartition your system, see section <A HREF="Multi-Disk-HOWTO-12.html#repartitioning">Repartitioning</A>. </DL> <P> <DL> <DT><B>Symptoms</B><DD><P>No room amidst plenty 2 <DT><B>Problem</B><DD><P>Running out of i-nodes has caused overflow in some ares, often in areas with many small files such as news spool. <DT><B>Solution</B><DD><P>Examine your partition usage using <CODE>df -i</CODE> and locate problem areas. Normally the problem is solved by reformatting using a higher number of i-nodes, see <CODE>mkfs(8)</CODE> and related man pages. </DL> <P> <P> <P> <HR> <A HREF="Multi-Disk-HOWTO-16.html">Next</A> <A HREF="Multi-Disk-HOWTO-14.html">Previous</A> <A HREF="Multi-Disk-HOWTO.html#toc15">Contents</A> </BODY> </HTML>