Given that we boot into a modern Linux distribution with the "/run" toplevel
directory, we can easily mount move the whole /run directory to the real
root in the end and have the complete initramfs later on in
/run/initramfs. All log files and /run states are still accessible and
to save space /run/initramfs can be removed later on.
Because the kernel does not mount a tmpfs on /run prior to unpacking the
initramfs cpio image, we have to copy ourselves very early to a tmpfs
and mount it on /run.
Due to lazy umount the old initramfs binaries should
be removed in the end by switch_root.
This feature can be turned on with "--prefix".
We want all "/var/run" information to live in /dev/.run, until the real
root is mounted.
Therefore we mount a tmpfs on /dev/.run, which can/will be bind/move mounted
on /var/run later on.
Format:
bond=<bondname>[:<bondslaves>:[:<options>]]
bondslaves is a comma-separated list of physical (ethernet) interfaces.
options is a comma-separated list on bonding options (modinfo bonding for
details) in format compatible with initscripts.
If options include multi-valued arp_ip_target option, then its values
should be separated by semicolon.
bond without parameters assumes bond=bond0:eth0,eth1:balance-rr
* SYNTAX
bridge=<bridgename>:<ethname>
If bridge without parameters, assume bridge=br0:eth0
* When <ethname> would be configured by network scripts, instead create a bridge named <bridgename> then add <ethname> to that bridge.
* Then $netif becomes <bridgename> instead of <ethname> and all existing scripts process netroot mount via this new $netif instead of <ethname>.
* Include a few test cases in NFS and NBD
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.
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
Will Woods