Postings by hw

Centos´s way of handling mdadm


what´s the proposed way of handling mdadm in Centos 7? I did not get
any notification when a disk in a RAID1 failed, and now that the
configuration has changed after resolving the problem, I might be
supposed to somehow update /etc/mdadm.conf.

Am I not supposed to be notified by default when something goes wrong
with an array? How do I update /etc/mdadm.conf?

I´m used to all this working automagically.

slow libreoffice


so what do I need to install to prevent libreoffice from being so slow
that it becomes unusable?

This issue has been there with Fedora years ago, and now there´s same
issue with Centos. Back then, there was a package you could install to
make it work at normal speeds, but last time I checked, this package
doesn´t exist anymore.

This issue is particular to the Fedora/Centos versions of libreoffice
and does not occur with other builds like the one you can download from
the libreoffice web site.

I was trying to make a chart and it became so slow that it´s unusable.

home on nfs


I have the home directory of a user on an nfs server and mount it on a
client. When the user logs in, they end up in the root directory rather
than in their actual home directory and need to cd into it.

The user can read and write to their home directory, so it kinda works
fine --- but only kinda. When the user starts emacs, some of the
settings in ~/.emacs are not applied, but the saved desktop is being

Both machines are running Centos 7.4. What could be wrong with the nfs

NUMA split mode?


HP says that what they call "NUMA split mode" should be disabled in the
BIOS of the Z800 workstation when running Linux. They are reasoning
that Linux kernels do not support this feature and even might not boot
if it´s enabled.

Since it apparently was years ago since they made this statement, I´m
wondering if I should still leave this feature disabled or not. More
recent kernels might support it, and it´s supposed to improve

Could someone explain what this feature actually is or does, and if
Centos kernels support it?

Intel turbo mode


is there a way in Centos to find out if the Intel turbo mode will be

Using the 'stress' utility and checking the frequency with cpupower
tells me that a CPU is running at it´s maximum frequency as reported by
cpupower --- and this frequency is less than the frequency it would run
at if it used the turbo mode. All the other CPUs are at their minimum
frequency. I have verified that turbo mode is enabled in the BIOS.

Is cpupower unable to report frequencies used in turbo mode despite it
always says it gets its information from the hardware?

how to prevent files and directories from being deleted?


how can I prevent files/directories like /var/run/mariadb from being
deleted on reboot? Lighttpd has the same problem.

This breaks services and makes servers non-restartable by anyone else
but the administrator who needs to re-create the needed files and
directories every time and has to figure out what selinux labels they
need. This causes unnecessary downtimes.

This is entirely inacceptable. This totally sucks.