130 lines
5.1 KiB
HTML
130 lines
5.1 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
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<HTML>
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<HEAD>
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<META NAME="GENERATOR" CONTENT="SGML-Tools 1.0.9">
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<TITLE>HOWTO: Multi Disk System Tuning: Questions and Answers</TITLE>
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<LINK HREF="Multi-Disk-HOWTO-20.html" REL=next>
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<LINK HREF="Multi-Disk-HOWTO-18.html" REL=previous>
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<LINK HREF="Multi-Disk-HOWTO.html#toc19" REL=contents>
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</HEAD>
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<BODY>
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<A HREF="Multi-Disk-HOWTO-20.html">Next</A>
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<A HREF="Multi-Disk-HOWTO-18.html">Previous</A>
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<A HREF="Multi-Disk-HOWTO.html#toc19">Contents</A>
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<HR>
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<H2><A NAME="s19">19. Questions and Answers</A></H2>
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<P>
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<!--
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disk!FAQ
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-->
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<!--
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disk!frequently asked questions
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-->
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This is just a collection of what I believe are the most common
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questions people might have. Give me more feedback and I will
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turn this section into a proper FAQ.
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<P>
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<UL>
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<LI>Q:How many physical disk drives (spindles) does a Linux system need?
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<P>A: Linux can run just fine on one drive (spindle). Having enough
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RAM (around 32 MB, and up to 64 MB) to support swapping is a
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better price/performance choice than getting a second disk.
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(E)IDE disk is usually cheaper (but a little slower) than SCSI.
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<P>
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</LI>
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<LI>Q: I have a single drive, will this HOWTO help me?
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<P>A: Yes, although only to a minor degree. Still, section
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<A HREF="Multi-Disk-HOWTO-6.html#physical-track-positioning">Physical Track Positioning</A>
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will offer you some gains.
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<P>
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</LI>
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<LI>Q: Are there any disadvantages in this scheme?
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<P>A: There is only a minor snag: if even a single partition overflows
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the system might stop working properly. The severity depends of course
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on what partition is affected. Still this is not hard to monitor, the
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command <CODE>df</CODE> gives you a good overview of the situation. Also check
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the swap partition(s) using <CODE>free</CODE> to make sure you are not about
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to run out of virtual memory.
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<P>
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</LI>
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<LI>Q: OK, so should I split the system into as many partitions
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as possible for a single drive?
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<P>A: No, there are several disadvantages to that. First of all maintenance
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becomes needlessly complex and you gain very little in this. In fact if your
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partitions are too big you will seek across larger areas than needed.
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This is a balance and dependent on the number of physical drives you have.
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<P>
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</LI>
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<LI>Q: Does that mean more drives allows more partitions?
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<P>A: To some degree, yes. Still, some directories should not be split
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off from root, check out the file system standards for more details.
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<P>
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</LI>
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<LI>Q: What if I have many drives I want to use?
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<P>A: If you have more than 3-4 drives you should consider using RAID of
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some form. Still, it is a good idea to keep your root partition on a
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simple partition without RAID, see section
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<A HREF="Multi-Disk-HOWTO-6.html#RAID">RAID</A> for more details.
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<P>
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</LI>
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<LI>Q: I have installed the latest Windows95 but cannot access this
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partition from within the Linux system, what is wrong?
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<P>A: Most likely you are using <CODE>FAT32</CODE> in your windows partition. It
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seems that Microsoft decided we needed yet another format, and this
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was introduced in their latest version of Windows95, called OSR2.
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The advantage is that this format is better suited to large drives.
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<P>You might also be interested to hear that Microsoft NT 4.0 does not
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support it yet either.
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<P>
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</LI>
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<LI>Q: I cannot get the disk size and partition sizes to match,
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something is missing. What has happened?
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<P>A:It is possible you have mounted a partition onto a mount point that
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was not an empty directory. Mount points are directories and if it
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is not empty the mounting will mask the contents. If you do the sums
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you will see the amount of disk space used in this directory is
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missing from the observed total.
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<P>To solve this you can boot from a rescue disk and see what is hiding
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behind your mount points and remove or transfer the contents by
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mounting the offending partition on a temporary mounting point. You
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might find it useful to have "spare" emergency mounting points ready
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made.
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<P>
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</LI>
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<LI>Q: It doesn't look like my swap partition is in use, how come?
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<P>A: It is possible that it has not been necessary to swap out,
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especially if you have plenty of RAM. Check your log files to see
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if you ran out of memory at one point or another, in that case
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your swap space should have been put to use. If not it is
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possible that either the swap partition was not assigned the
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right number, that you did not prepare it with <CODE>mkswap</CODE> or
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that you have not done <CODE>swapon</CODE> or added it to your
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<A HREF="file:///etc/fstab">/etc/fstab</A>
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file.
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<P>
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<P>
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<P>
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</LI>
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<LI>Q: What is this Nyx that is mentioned several times here?
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<P>A: It is a large free Unix system with currently about 10000 users.
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I use it for my web pages for this HOWTO as well as a source
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of ideas for a setup of large Unix systems. It has been running for
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many years and has a quite stable setup. For more information you can
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view the
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<A HREF="http://www.nyx.net">Nyx homepage</A>
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which also gives you information on how to get your own free account.
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<P>
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</LI>
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</UL>
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<P>
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<P>
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<HR>
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<A HREF="Multi-Disk-HOWTO-20.html">Next</A>
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<A HREF="Multi-Disk-HOWTO-18.html">Previous</A>
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<A HREF="Multi-Disk-HOWTO.html#toc19">Contents</A>
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</BODY>
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</HTML>
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