Merge tag 'nfsd-4.7-2' of git://linux-nfs.org/~bfields/linux

[linux.git] / Documentation / Changes

Intro
=====

This document is designed to provide a list of the minimum levels of
software necessary to run the 3.0 kernels.

This document is originally based on my "Changes" file for 2.0.x kernels
and therefore owes credit to the same people as that file (Jared Mauch,
Axel Boldt, Alessandro Sigala, and countless other users all over the
'net).

Current Minimal Requirements
============================

Upgrade to at *least* these software revisions before thinking you've
encountered a bug!  If you're unsure what version you're currently
running, the suggested command should tell you.

Again, keep in mind that this list assumes you are already functionally
running a Linux kernel.  Also, not all tools are necessary on all
systems; obviously, if you don't have any ISDN hardware, for example,
you probably needn't concern yourself with isdn4k-utils.

o  GNU C                  3.2                     # gcc --version
o  GNU make               3.80                    # make --version
o  binutils               2.12                    # ld -v
o  util-linux             2.10o                   # fdformat --version
o  module-init-tools      0.9.10                  # depmod -V
o  e2fsprogs              1.41.4                  # e2fsck -V
o  jfsutils               1.1.3                   # fsck.jfs -V
o  reiserfsprogs          3.6.3                   # reiserfsck -V
o  xfsprogs               2.6.0                   # xfs_db -V
o  squashfs-tools         4.0                     # mksquashfs -version
o  btrfs-progs            0.18                    # btrfsck
o  pcmciautils            004                     # pccardctl -V
o  quota-tools            3.09                    # quota -V
o  PPP                    2.4.0                   # pppd --version
o  isdn4k-utils           3.1pre1                 # isdnctrl 2>&1|grep version
o  nfs-utils              1.0.5                   # showmount --version
o  procps                 3.2.0                   # ps --version
o  oprofile               0.9                     # oprofiled --version
o  udev                   081                     # udevd --version
o  grub                   0.93                    # grub --version || grub-install --version
o  mcelog                 0.6                     # mcelog --version
o  iptables               1.4.2                   # iptables -V
o  openssl & libcrypto    1.0.0                   # openssl version
o  bc                     1.06.95                 # bc --version


Kernel compilation
==================

GCC
---

The gcc version requirements may vary depending on the type of CPU in your
computer.

Make
----

You will need GNU make 3.80 or later to build the kernel.

Binutils
--------

Linux on IA-32 has recently switched from using as86 to using gas for
assembling the 16-bit boot code, removing the need for as86 to compile
your kernel.  This change does, however, mean that you need a recent
release of binutils.

Perl
----

You will need perl 5 and the following modules: Getopt::Long, Getopt::Std,
File::Basename, and File::Find to build the kernel.

BC
--

You will need bc to build kernels 3.10 and higher


OpenSSL
-------

Module signing and external certificate handling use the OpenSSL program and
crypto library to do key creation and signature generation.

You will need openssl to build kernels 3.7 and higher if module signing is
enabled.  You will also need openssl development packages to build kernels 4.3
and higher.


System utilities
================

Architectural changes
---------------------

DevFS has been obsoleted in favour of udev
(http://www.kernel.org/pub/linux/utils/kernel/hotplug/)

32-bit UID support is now in place.  Have fun!

Linux documentation for functions is transitioning to inline
documentation via specially-formatted comments near their
definitions in the source.  These comments can be combined with the
SGML templates in the Documentation/DocBook directory to make DocBook
files, which can then be converted by DocBook stylesheets to PostScript,
HTML, PDF files, and several other formats.  In order to convert from
DocBook format to a format of your choice, you'll need to install Jade as
well as the desired DocBook stylesheets.

Util-linux
----------

New versions of util-linux provide *fdisk support for larger disks,
support new options to mount, recognize more supported partition
types, have a fdformat which works with 2.4 kernels, and similar goodies.
You'll probably want to upgrade.

Ksymoops
--------

If the unthinkable happens and your kernel oopses, you may need the
ksymoops tool to decode it, but in most cases you don't.
It is generally preferred to build the kernel with CONFIG_KALLSYMS so
that it produces readable dumps that can be used as-is (this also
produces better output than ksymoops).  If for some reason your kernel
is not build with CONFIG_KALLSYMS and you have no way to rebuild and
reproduce the Oops with that option, then you can still decode that Oops
with ksymoops.

Module-Init-Tools
-----------------

A new module loader is now in the kernel that requires module-init-tools
to use.  It is backward compatible with the 2.4.x series kernels.

Mkinitrd
--------

These changes to the /lib/modules file tree layout also require that
mkinitrd be upgraded.

E2fsprogs
---------

The latest version of e2fsprogs fixes several bugs in fsck and
debugfs.  Obviously, it's a good idea to upgrade.

JFSutils
--------

The jfsutils package contains the utilities for the file system.
The following utilities are available:
o fsck.jfs - initiate replay of the transaction log, and check
  and repair a JFS formatted partition.
o mkfs.jfs - create a JFS formatted partition.
o other file system utilities are also available in this package.

Reiserfsprogs
-------------

The reiserfsprogs package should be used for reiserfs-3.6.x
(Linux kernels 2.4.x). It is a combined package and contains working
versions of mkreiserfs, resize_reiserfs, debugreiserfs and
reiserfsck. These utils work on both i386 and alpha platforms.

Xfsprogs
--------

The latest version of xfsprogs contains mkfs.xfs, xfs_db, and the
xfs_repair utilities, among others, for the XFS filesystem.  It is
architecture independent and any version from 2.0.0 onward should
work correctly with this version of the XFS kernel code (2.6.0 or
later is recommended, due to some significant improvements).

PCMCIAutils
-----------

PCMCIAutils replaces pcmcia-cs. It properly sets up
PCMCIA sockets at system startup and loads the appropriate modules
for 16-bit PCMCIA devices if the kernel is modularized and the hotplug
subsystem is used.

Quota-tools
-----------

Support for 32 bit uid's and gid's is required if you want to use
the newer version 2 quota format.  Quota-tools version 3.07 and
newer has this support.  Use the recommended version or newer
from the table above.

Intel IA32 microcode
--------------------

A driver has been added to allow updating of Intel IA32 microcode,
accessible as a normal (misc) character device.  If you are not using
udev you may need to:

mkdir /dev/cpu
mknod /dev/cpu/microcode c 10 184
chmod 0644 /dev/cpu/microcode

as root before you can use this.  You'll probably also want to
get the user-space microcode_ctl utility to use with this.

udev
----
udev is a userspace application for populating /dev dynamically with
only entries for devices actually present.  udev replaces the basic
functionality of devfs, while allowing persistent device naming for
devices.

FUSE
----

Needs libfuse 2.4.0 or later.  Absolute minimum is 2.3.0 but mount
options 'direct_io' and 'kernel_cache' won't work.

Networking
==========

General changes
---------------

If you have advanced network configuration needs, you should probably
consider using the network tools from ip-route2.

Packet Filter / NAT
-------------------
The packet filtering and NAT code uses the same tools like the previous 2.4.x
kernel series (iptables).  It still includes backwards-compatibility modules
for 2.2.x-style ipchains and 2.0.x-style ipfwadm.

PPP
---

The PPP driver has been restructured to support multilink and to
enable it to operate over diverse media layers.  If you use PPP,
upgrade pppd to at least 2.4.0.

If you are not using udev, you must have the device file /dev/ppp
which can be made by:

mknod /dev/ppp c 108 0

as root.

Isdn4k-utils
------------

Due to changes in the length of the phone number field, isdn4k-utils
needs to be recompiled or (preferably) upgraded.

NFS-utils
---------

In ancient (2.4 and earlier) kernels, the nfs server needed to know
about any client that expected to be able to access files via NFS.  This
information would be given to the kernel by "mountd" when the client
mounted the filesystem, or by "exportfs" at system startup.  exportfs
would take information about active clients from /var/lib/nfs/rmtab.

This approach is quite fragile as it depends on rmtab being correct
which is not always easy, particularly when trying to implement
fail-over.  Even when the system is working well, rmtab suffers from
getting lots of old entries that never get removed.

With modern kernels we have the option of having the kernel tell mountd
when it gets a request from an unknown host, and mountd can give
appropriate export information to the kernel.  This removes the
dependency on rmtab and means that the kernel only needs to know about
currently active clients.

To enable this new functionality, you need to:

  mount -t nfsd nfsd /proc/fs/nfsd

before running exportfs or mountd.  It is recommended that all NFS
services be protected from the internet-at-large by a firewall where
that is possible.

mcelog
------

On x86 kernels the mcelog utility is needed to process and log machine check
events when CONFIG_X86_MCE is enabled. Machine check events are errors reported
by the CPU. Processing them is strongly encouraged.

Getting updated software
========================

Kernel compilation
******************

gcc
---
o  <ftp://ftp.gnu.org/gnu/gcc/>

Make
----
o  <ftp://ftp.gnu.org/gnu/make/>

Binutils
--------
o  <ftp://ftp.kernel.org/pub/linux/devel/binutils/>

OpenSSL
-------
o  <https://www.openssl.org/>

System utilities
****************

Util-linux
----------
o  <ftp://ftp.kernel.org/pub/linux/utils/util-linux/>

Ksymoops
--------
o  <ftp://ftp.kernel.org/pub/linux/utils/kernel/ksymoops/v2.4/>

Module-Init-Tools
-----------------
o  <ftp://ftp.kernel.org/pub/linux/kernel/people/rusty/modules/>

Mkinitrd
--------
o  <https://code.launchpad.net/initrd-tools/main>

E2fsprogs
---------
o  <http://prdownloads.sourceforge.net/e2fsprogs/e2fsprogs-1.29.tar.gz>

JFSutils
--------
o  <http://jfs.sourceforge.net/>

Reiserfsprogs
-------------
o  <http://www.kernel.org/pub/linux/utils/fs/reiserfs/>

Xfsprogs
--------
o  <ftp://oss.sgi.com/projects/xfs/>

Pcmciautils
-----------
o  <ftp://ftp.kernel.org/pub/linux/utils/kernel/pcmcia/>

Quota-tools
----------
o  <http://sourceforge.net/projects/linuxquota/>

DocBook Stylesheets
-------------------
o  <http://sourceforge.net/projects/docbook/files/docbook-dsssl/>

XMLTO XSLT Frontend
-------------------
o  <http://cyberelk.net/tim/xmlto/>

Intel P6 microcode
------------------
o  <https://downloadcenter.intel.com/>

udev
----
o <http://www.freedesktop.org/software/systemd/man/udev.html>

FUSE
----
o <http://sourceforge.net/projects/fuse>

mcelog
------
o <http://www.mcelog.org/>

Networking
**********

PPP
---
o  <ftp://ftp.samba.org/pub/ppp/>

Isdn4k-utils
------------
o  <ftp://ftp.isdn4linux.de/pub/isdn4linux/utils/>

NFS-utils
---------
o  <http://sourceforge.net/project/showfiles.php?group_id=14>

Iptables
--------
o  <http://www.iptables.org/downloads.html>

Ip-route2
---------
o  <https://www.kernel.org/pub/linux/utils/net/iproute2/>

OProfile
--------
o  <http://oprofile.sf.net/download/>

NFS-Utils
---------
o  <http://nfs.sourceforge.net/>