mirror of
https://github.com/NixOS/nix.git
synced 2024-10-30 22:00:57 +00:00
93 lines
3.2 KiB
XML
93 lines
3.2 KiB
XML
<appendix xmlns="http://docbook.org/ns/docbook"
|
||
xmlns:xlink="http://www.w3.org/1999/xlink">
|
||
|
||
<title>Troubleshooting</title>
|
||
|
||
|
||
<para>This section provides solutions for some common problems. See
|
||
the <link xlink:href="http://bugs.strategoxt.org/browse/NIX">Nix
|
||
bug tracker</link> for a list of currently known issues.</para>
|
||
|
||
|
||
<section><title>Collisions in <command>nix-env</command></title>
|
||
|
||
<para>Symptom: when installing or upgrading, you get an error message such as
|
||
|
||
<screen>
|
||
$ nix-env -i docbook-xml
|
||
...
|
||
adding /nix/store/s5hyxgm62gk2...-docbook-xml-4.2
|
||
collission between `/nix/store/s5hyxgm62gk2...-docbook-xml-4.2/xml/dtd/docbook/calstblx.dtd'
|
||
and `/nix/store/06h377hr4b33...-docbook-xml-4.3/xml/dtd/docbook/calstblx.dtd'
|
||
at /nix/store/...-builder.pl line 62.</screen>
|
||
|
||
</para>
|
||
|
||
<para>The cause is that two installed packages in the user environment
|
||
have overlapping filenames (e.g.,
|
||
<filename>xml/dtd/docbook/calstblx.dtd</filename>. This usually
|
||
happens when you accidentally try to install two versions of the same
|
||
package. For instance, in the example above, the Nix Packages
|
||
collection contains two versions of <literal>docbook-xml</literal>, so
|
||
<command>nix-env -i</command> will try to install both. The default
|
||
user environment builder has no way to way to resolve such conflicts,
|
||
so it just gives up.</para>
|
||
|
||
<para>Solution: remove one of the offending packages from the user
|
||
environment (if already installed) using <command>nix-env
|
||
-e</command>, or specify exactly which version should be installed
|
||
(e.g., <literal>nix-env -i docbook-xml-4.2</literal>).</para>
|
||
|
||
<para>Alternatively, you can modify the user environment builder
|
||
script (in
|
||
<filename><replaceable>prefix</replaceable>/share/nix/corepkgs/buildenv/builder.pl</filename>)
|
||
to implement some conflict resolution policy. E.g., the script could
|
||
be modified to rename conflicting file names, or to pick one over the
|
||
other.</para>
|
||
|
||
</section>
|
||
|
||
|
||
<section><title><quote>Too many links</quote> error in the Nix
|
||
store</title>
|
||
|
||
|
||
<para>Symptom: when building something, you get an error message such as
|
||
|
||
<screen>
|
||
...
|
||
<literal>mkdir: cannot create directory `/nix/store/<replaceable>name</replaceable>': Too many links</literal></screen>
|
||
|
||
</para>
|
||
|
||
<para>This is usually because you have more than 32,000 subdirectories
|
||
in <filename>/nix/store</filename>, as can be seen using <command>ls
|
||
-l</command>:
|
||
|
||
<screen>
|
||
$ ls -l /nix/store
|
||
drwxrwxrwt 32000 nix nix 4620288 Sep 8 15:08 store</screen>
|
||
|
||
The <literal>ext2</literal> file system is limited to a inode link
|
||
count of 32,000 (each subdirectory increasing the count by one).
|
||
Furthermore, the <literal>st_nlink</literal> field of the
|
||
<function>stat</function> system call is a 16-bit value.</para>
|
||
|
||
<para>This only happens on very large Nix installations (such as build
|
||
machines).</para>
|
||
|
||
<para>Quick solution: run the garbage collector. You may want to use
|
||
the <option>--max-links</option> option.</para>
|
||
|
||
<para>Real solution: put the Nix store on a file system that supports
|
||
more than 32,000 subdirectories per directory, such as ReiserFS.
|
||
(This doesn’t solve the <literal>st_nlink</literal> limit, but
|
||
ReiserFS lies to the kernel by reporting a link count of 1 if it
|
||
exceeds the limit.)</para>
|
||
|
||
</section>
|
||
|
||
|
||
|
||
</appendix>
|