Talked with Debian nbdroot author and he agreed we shouldn't support their obsolete syntax in dracut.
Their root=/dev/nbd[0-9] is no longer needed. Also their syntax was very standardized requiring
a separate boot= parameter.
- Remove root=nfs nfsroot=...
- Remove root=nfs4 nfsroot=...
- Remove root=/dev/nfs4 nfsroot=...
- Legacy nfsroot= without root=/dev/nfs should be unsupported according to the nfsroot.txt.
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=Documentation/filesystems/nfsroot.txt
45 root=/dev/nfs
46
47 This is necessary to enable the pseudo-NFS-device. Note that it's not a
48 real device but just a synonym to tell the kernel to use NFS instead of
49 a real device.
Pretty much everyone uses it, and things break of userspace
does not make it because of a case of mistaken identities.
/sbin/start_udev on FC11, I am looking at you.
The Bug causing dhclient to recall BIND has been identified:
dhclient-script runs with #!/bin/sh -e, causing setup_interface
to fail if no hostname is provided by dhcp as it is the last statement
in that function.
This introduces a new cmdline argument bootdev, to support the case
where multiple nics need to be up before the netroot handler is called.
Cases involved might be bonding, iscsi multipathing, bonding, ...
This argument is required to decide which interface is the primary to
use for dhcp root-path, default gw, etc.
When multiple ip= items are present on the cmdline, the ip= parser
now enforces the presence of <dev> further demands that the new argument
bootdev contains the name of the primary interface. Configurtion if of
course still delegated to netroot but in is enhance to ensure that netroot
"waits" for all required interfaces to be up.
Example: root=dhcp ip=eth0:dhcp ip=client-ip:::netmask::eth1:off bootdev=eth0
First, the ip= cmdline parser ensures that all ip items contain a <dev> then
checks the ip items and checks as well that an ip= item for the given bootdev
was found.
When the first netroot starts, probably for eth1, it checks wheter interface
configuration for all interfaces is available. If not it exits. The second
start of netroot (eth0, which was a bit delayed because of dhcp) sees that
all interfaces are present, configures them and continues.
Instead of configuring devices when they are ready, ifup and
dhclient-script write script files which are then sourced by
netroot.
This solves the problem of having multiple interfaces and not knowing
which one to use for dhcp or default route. This way, netroot (which
is serialized anyway) configures the interface before calling the root
handler and deconfigures it if the handler failed.
Example: root=nfs:server:path and ip=dhcp with eth0 and eth1 receiving
a dhcp reply, but eth0 is the correct one to use.
Assuming eth1 is the first to receive the dhcp-reply, netroot starts
and configures eth1. nfsroot is run but fails, so eth1 is deconfigured. If
eth0 has received a dhcp-reply (or not, then we wait) the other locked
netroot process starts and tries with eth0 and succeeds.
Currently network configuration is launched by udev as soon as it
discovers a driver. This isn't such a good idea since we don't know
if network configuration is actually required. Change this by writing
the udev rules on the fly if required.
As with other netroot boot arguments ip= lines should be parsed and
checked. Having this has the advantage that other cmdline scripts
can tell the ip= parser if dhcp or ip=:srv:... is needed, like
parse-root.sh (renamed dhcp-fallback) or parse-nfsroot do.
The nfs test-suite has one check which uses static ip lines, but
the autoconf param is wrong. Fixed this as well.
This introduces detailed cmdline parsing, warning or aborting if the
cmdline does not contain arguments according to the spec.
Makeing sure the parsers don't just call getarg for netroot et al,
allows their reuse inside netroot to analyse dhcp root-path as well.
Hence we can get rid of the current netroot hooks. The hook itself stays
in order to add further modules which should run before netroot handlers
are called.
This has one drawback: nfsroot needs some more logic to handle nfs
specific data inside dhcp root-path.
The parsers have been writting according to current discussions about
cmdline arguments. This lead to the "discovery" that some test-cases
violate the spec. These tests have not been removed, but change to
"must fail".
When die()'ing inside scripts that are udev run, a simple echo isn't
good, udev usually swallows that. Routing messages to /dev/kmsg
ensures they appear on screen and in addition are easily saved through
dmesg.
Printing out an errormessage and quitting is easier if there's a function
to call. If the script calling die has exit trapped, like in init, the
emergency_shell is automatically called.
Multiline conditionals ( && { ... } ) should use if, function
declarations go to the top of the file, add/update comments and remove
some unnecessary clutter.
Saveing ip= options in ifup makes the information available for
later use. This solves the problem how to write static ip configuration
in ifcfg files.
This is mostly about style: Doing stuff after a successful mount
should go into pre-pivot.
In addition this corrects the case where the used netif is not eth0
base/init uses [ -d "$NEWROOT/proc" ] to check if root is mounted
or not. Netroot should do the same. In addition this gets rid of
another file in /tmp, since /tmp/netroot.done isn't needed anymore.
Having two files which are used more or less at the same time isn't
that easy to handle and read. Instead, move the contents of netroot.info
to root.info and only use root.info. This is cleaner and makes debugging
easier.
This is probably not necessary, but paranoia dictates that the actual
netroot handlers should check if all three required arguments (netif,
root, NEWROOT) are there and useable.
rpc.statd is only needed for NFSv4, because it's required for
locking. We don't support locking for NFSv2/3, so start it only
if we are mount from NFSv4.
This patch enhances nfsroot and the nfs test-suite with compatibility
for debian based distros. This is mainly the difference of using
portmap instead of rpcbind and the missing file /etc/netconfig
With this change, we can now use LUKS and LVM over NBD. There are
some decisions to be made regarding where we should get the fstype
and fsoptions from (DHCP root vs rootfstype= etc), but the basic
functionality is there.
This adds support for a command line option netroot=, which is currently
equivalent to root=. This will allow us to break out handling in NBD and
iSCSI to support constructs such as "root=LABEL=/ netroot=dhcp" to make
use of our block device handling with network attached devices.
iSCSI has not been changed in this patch as I don't currently have a way
to test it.
This implements a default path of /tftpboot/%s if no path is provided,
and adds host name substitution for %s, with a fall back to the IP address,
as provided by the kernel's nfsroot handling.
The test suite is updated to test this functionality.
Probe for NFS and NBD capability before trying to load their modules
in case they are built into the kernel. Ugly use of flag files, but
avoids the need for grep to be on the image.
Parse and convert commandline options in the cmdline hook, and
fill in the missing pieces in the netroot hook. This also allows
root=dhcp to work as expected.
/sbin/netroot is a jumping off point to allow various network
root devices to share infrastructure. It will loop over scriptlets
in the netroot handler, looking for a handler to run for this type
of netroot. Handlers can do choose to act based on command line
options to the kernel, or via DHCP options received on this interface.
They should massage root= into a form suitable for their handler.
I noticed when doing the block root= parser that resume
didn't support labeled resume devices. Fix that up and
get rid of a dependency on /bin/echo in the process.
Now init checks that we understood the root= option, and can
act upon it, presenting and error if not. Also, clean up the
generation of udev rules such that we don't require /bin/echo.
First, add a check script to 99base to ensure that it will load its
prerequisites.
Second, disable the udev magic dracut normally uses when generating
test images -- it was causing random failures when creating the test
root filesystem, presumably due to race conditions between the
rootfs creation scripts and udev.
Third, consolidate the rootfs creation scripts into one script.
This gets rid of the need to have potentially security-sensitive files
like /etc/passwd and /etc/group in the initramfs, and makes the initramfs
a bit smaller. We trust the final userspace to do The Right Thing when
assigning user/group ownership to devices.
This also eliminates --skip-missing. Check scripts should now check
to ensure that any files and settings they will copy from the host
system actually exist when called without arguments.
The check scripts are also updated to not try to source dracut-functions
which(1) is a perfectly good way of checking if a command is on the path.
Harald Hoyer