Partially reverts commit 901163c0c7.
This has broken remote SSH into initrd because ${cfg.shell} is not
expanded. Also, nsswitch is useless without libnss_files.so which
are installed by initrd-ssh.
This hopefully fixes intermittent test failures like
http://hydra.nixos.org/build/29962437
router# [ 240.128835] INFO: task mke2fs:99 blocked for more than 120 seconds.
router# [ 240.130135] Not tainted 3.18.25 #1-NixOS
router# [ 240.131110] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
assuming that these are caused by high load on the host.
$d should be $sd, this causes resume from hibernate to fail if
resumeDevice is not explicitly set in config. Introduced in commit:
'stage-1: Shut up warnings about swap devices that don't exist yet'
The PID 1 shell is executed as the last command in a sh invocation. Some
shells implicitly use exec for that, but the current busybox ash does not,
so the shell gets a wrong PID. Spell out the exec.
The old boot.spl.hostid option was not working correctly due to an
upstream bug.
Instead, now we will create the /etc/hostid file so that all applications
(including the ZFS kernel modules, ZFS user-space applications and other
unrelated programs) pick-up the same system-wide host id. Note that glibc
(and by extension, the `hostid` program) also respect the host id configured in
/etc/hostid, if it exists.
The hostid option is now mandatory when using ZFS because otherwise, ZFS will
require you to force-import your ZFS pools if you want to use them, which is
undesirable because it disables some of the checks that ZFS does to make sure it
is safe to import a ZFS pool.
The /etc/hostid file must also exist when booting the initrd, before the SPL
kernel module is loaded, so that ZFS picks up the hostid correctly.
The complexity in creating the /etc/hostid file is due to having to
write the host ID as a 32-bit binary value, taking into account the
endianness of the machine, while using only shell commands and/or simple
utilities (to avoid exploding the size of the initrd).