diff --git a/man/systemd-sysctl.service.xml b/man/systemd-sysctl.service.xml index e3d33bf1f4..a817a6b33f 100644 --- a/man/systemd-sysctl.service.xml +++ b/man/systemd-sysctl.service.xml @@ -84,7 +84,19 @@ - Verify sysctl values after write. + After systemd-sysctl successfully writes a value to a sysctl variable, the + variable is read back and verified to match the value that was written. If the variable cannot be + read back, or if the returned value differs from the written value, the write operation is + considered to have failed. To detect such failures reliably, it is recommended to also specify + , and to ensure that the settings being applied are not prefixed with + - (see + sysctl.d5 + for details). This mode is disabled by default, since the format accepted by the kernel may differ + from the format returned when the variable is read back, or the kernel may normalize the input. As + a result, verification may not work reliably in all cases. Therefore, this option is best used + together with explicitly specified configuration files or settings provided through + , or with to restrict the set of sysctl + variables being written. @@ -151,13 +163,15 @@ kernel.core_pattern = |/usr/libexec/abrt-hook-ccpp %s %c %p %u %g %t %P %I - Update coredump handler configuration + Update and verify coredump handler configuration - # /usr/lib/systemd/systemd-sysctl --prefix kernel.core_pattern + # /usr/lib/systemd/systemd-sysctl --prefix kernel.core_pattern --strict --verify This searches all the directories listed in - sysctl.d5 - for configuration files and writes /proc/sys/kernel/core_pattern. + sysctl.d5 for + configuration files and writes /proc/sys/kernel/core_pattern. The sysctl variable + is read back and verified. If writing or verification fails, the command exits with a non-zero status, + unless the corresponding setting is prefixed with -.