A common usage pattern for zgenhostid, including in the ZFS dracut
module, is running it as:
zgenhostid $(hostid)
However, zgenhostid only accepted hostid arguments greater than 0, which
meant that, when the output of hostid(1) was "00000000", zgenhostid
would error out, even though 0 is a possible return value for the
gethostid(3) function used by hostid(1):
- On current musl libc, gethostid(3) is a stub that always returns 0.
- On glibc, gethostid(3) will return 0 if /etc/hostid exists but is
smaller than 4 bytes.
In these cases, it makes more sense for zgenhostid to treat a value of 0
as other parts of the zfs codebase do, meaning that a hostid value
couldn't be determined; therefore, it should attempt to generate a
random value to write into /etc/hostid.
The manpage and usage output have been updated to reflect this.
Whitespace has also been fixed in the usage output.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Georgy Yakovlev <gyakovlev@gentoo.org>
Reviewed-by: Andrew J. Hesford <ajh@sideband.org>
Signed-off-by: Érico Rolim <erico.erc@gmail.com>
Closes#11174Closes#11189
It was discovered that dracut scripts and zgenhostid
always generate little-endian /etc/hostid.
This commit provides simple endianess-aware binary
and updates the scripts to use it.
New features include:
-f flag to force overwrite.
-o flag to write to different file (for dracut)
accepting both 0x01234567 and 01234567 values as input
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Signed-off-by: Georgy Yakovlev <gyakovlev@gentoo.org>
Closes#10887Closes#10925
Not all systems / distros have a `/bin/bash`, and these scripts are
more difficult to run at development time.
For example, my system is NixOS which doesn't have a /bin/bash. This
is not a problem for NixOS building ZFS as a package: the build
environment automatically replaces these shebangs with corrected
paths.
The problem is much more annoying at development time: either the
scripts don't run, or I correct them for my local machine and deal with
a perpetually dirty work tree.
Before committing this patch I confirmed there are existing scripts
which use `/usr/bin/env` to locate bash, so I am thinking this is a
safe transformation.
There are a handful of other shebangs in this repository which don't
work on my system. This patch is useful on its own specifically for
`commitcheck.sh`, otherwise I can't validate my commits before
submission.
Here are the remaining shebangs which NixOS systems won't have:
1274 #!/bin/ksh -p
91 #!/bin/ksh
89 #! /bin/ksh -p
2 #!/bin/sed -f
1 #!/usr/bin/perl -w
1 #!/usr/bin/ksh
1 #!/bin/nawk -f
plus this which will create an invalid shebang in
`tests/zfs-tests/tests/functional/mv_files/mv_files_common.kshlib`:
echo "#!/bin/ksh" > $TEST_BASE_DIR/exitsZero.ksh
I chose to leave those alone for now, and gauge the interest in this
much smaller patch first.
The fixes for these are easy enough by simply using `/usr/bin/env ksh`:
91 #!/bin/ksh
1 #!/usr/bin/ksh
The fix for the other set is much trickier. Quoting the GNU coreutils
manual:
Most operating systems (e.g. GNU/Linux, BSDs) treat all text after
the first space as a single argument. When using env in a script it
is thus not possible to specify multiple arguments.
and not all `env`'s support arguments.
Mine (GNU Coreutils 8.31) does, though this feature is new since
April 2018, GNU Coreutils 8.30:
https://git.savannah.gnu.org/cgit/coreutils.git/commit/?id=668306ed86c8c79b0af0db8b9c882654ebb66db2
and worse, requires the -S argument:
-S, --split-string=S process and split S into separate arguments;
used to pass multiple arguments on shebang
lines
Example:
$ seq 1 2 | $(nix-build '<nixpkgs>' -A coreutils)/bin/env "sort -nr"
/nix/[...]-coreutils-8.31/bin/env: ‘sort -nr’: No such file or directory
/nix/[...]-coreutils-8.31/bin/env: use -[v]S to pass options in shebang lines
$ seq 1 2 | $(nix-build '<nixpkgs>' -A coreutils)/bin/env "-S sort -nr"
2
1
GNU Coreutils says FreeBSD's `env` does, though I wonder if FreeBSD's
would be unhappy with the `-S`:
https://www.gnu.org/software/coreutils/manual/html_node/env-invocation.html#env-invocation
BusyBox v1.30.1 does not, and does not have a `-S`-like option:
$ seq 1 2 | $(nix-build '<nixpkgs>' -A busybox)/bin/env "sort -nr"
env: can't execute 'sort -nr': No such file or directory
Toybox 0.8.1 also does not, and also does not have a `-S` option:
$ seq 1 2 | $(nix-build '<nixpkgs>' -A toybox)/bin/env "sort -nr"
env: exec sort -nr: No such file or directory
---
At any rate, if this patch merges and the remaining ~1,500 are updated,
the much larger patch should probably include a checkstyle-like test
asserting all new shebangs use `/usr/bin/env`. I also don't mind
dealing with NixOS weirdness if the project would prefer that.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Ryan Moeller <ryan@iXsystems.com>
Signed-off-by: Graham Christensen <graham@grahamc.com>
Closes#9893
Turning the multihost property on requires that a hostid be set to allow
ZFS to determine when a foreign system is attemping to import a pool.
The error message instructing the user to set a hostid refers to
genhostid(1).
Genhostid(1) is not available on SUSE Linux. This commit adds a script
modeled after genhostid(1) for those users.
Zgenhostid checks for an /etc/hostid file; if it does not exist, it
creates one and stores a value. If the user has provided a hostid as an
argument, that value is used. Otherwise, a random hostid is generated
and stored.
This differs from the CENTOS 6/7 versions of genhostid, which overwrite
the /etc/hostid file even though their manpages state otherwise.
A man page for zgenhostid is added. The one for genhostid is in (1), but
I put zgenhostid in (8) because I believe it's more appropriate.
The mmp tests are modified to use zgenhostid to set the hostid instead
of using the spl_hostid module parameter. zgenhostid will not replace
an existing /etc/hostid file, so new mmp_clear_hostid calls are
required.
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Olaf Faaland <faaland1@llnl.gov>
Closes#6358Closes#6379
