1 | <?xml version="1.0" encoding="ISO-8859-1"?> |
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2 | <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" |
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3 | "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ |
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4 | <!ENTITY % general-entities SYSTEM "../../general.ent"> |
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5 | %general-entities; |
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6 | ]> |
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7 | |
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8 | <sect1 id="ch-temp-system-choose"> |
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9 | <?dbhtml filename="choose.html"?> |
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10 | |
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11 | <title>To Boot or to Chroot?</title> |
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12 | |
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13 | <para os="a">There are two different ways you can proceed from this point |
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14 | to build the final system. You can build a kernel, a bootloader, and |
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15 | a few other utilities, boot into the temporary system, and build the |
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16 | rest there. Alternatively, you can mount a few virtual filesystems and |
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17 | chroot into the temporary system.</para> |
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18 | |
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19 | <para os="b">The <command>chroot</command> (change root) program is used to |
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20 | enter a virtual environment and start a new shell whose root directory will |
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21 | be set to the CLFS partition. This is very similar to rebooting and |
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22 | instructing the kernel to mount the CLFS partition as the root partition. |
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23 | The major advantage is that <quote>chrooting</quote> allows the builder to |
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24 | continue using the host while CLFS is being built. While waiting for package |
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25 | compilation to complete, a user can switch to a different virtual console |
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26 | (VC) or X desktop and continue using the computer as normal.</para> |
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27 | |
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28 | <!-- We also describe some alternative booting methods in <xref linkend="ch-boot-whatnext"/> --> |
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29 | |
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30 | <para os="c">The main downside to chrooting is that you are more limited in |
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31 | when you can use it - booting will always work for any CLFS build, but the |
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32 | chroot method can only be used when you are building on the same |
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33 | architecture. For example, if you are building on, and for, an x86 system, |
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34 | you can simply chroot. Booting is required when you are compiling for a |
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35 | different architecture, such as building a PowerPC system from an x86. The |
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36 | rule of thumb here is that if the architectures match and you are running |
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37 | the same series kernel (specifically, a &glibc-kernel-version; or newer |
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38 | Linux kernel) you can just chroot. If you aren't running the same series |
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39 | kernel, or are wanting to run a different ABI, you will need to use the boot |
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40 | option.</para> |
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41 | |
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42 | <para os="d">If you are in any doubt about this, you can try the following |
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43 | commands to see if you can chroot:</para> |
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44 | |
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45 | <screen os="e"><userinput>/tools/lib/libc.so.6 |
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46 | /tools/bin/gcc -v</userinput></screen> |
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47 | |
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48 | <para os="f">If either of these commands fail, you will have to follow the |
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49 | boot method.</para> |
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50 | |
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51 | <para os="g">For the boot method, follow <xref linkend="chapter-boot"/>.</para> |
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52 | |
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53 | <para os="h">For the chroot method, follow <xref linkend="chapter-chroot"/>.</para> |
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54 | |
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55 | </sect1> |
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