Settings in /etc/sysctl.conf overwritten [SOLVED]

I added a new line to /etc/sysctl.conf setting the vm.dirty_ratio to 3 (line is simply `vm.dirty_ratio = 3`). I can invoke it by running `sysctl -p` so I know the syntax is correct. This setting is however not loaded upon a reboot. The systemd-sysctl.service is however kicked off just fine and completes without errors. I have also tried removing the line from /etc/sysctl.conf and placing it in /etc/sysctl.d/dirty.conf but again, it is not honored at boot. What am I doing wrong?
EDIT: The solution is in post #31 - acknowledgement to chp for pointing me to it. Note that I also changed to topic to a more relevant one.
Last edited by graysky (2013-08-10 12:27:41)

Guess I'm stumped. I just spun up an Arch VM, pasted in the /etc/sysctl.conf below and reboot it. All the settings in the file in the VM are applied. If Leonid's guess that something is overriding these values on my workstation, I would like to figure out what it is and shut it down. To keep things simple, I booted into the stock ARCH kernel; here are the services I have active:
UNIT LOAD ACTIVE SUB DESCRIPTION
proc-sys-fs-binfmt_misc.automount loaded active waiting Arbitrary Executable File Formats File System Automo
sys-devices-pci0000:00-0000:00:19.0-net-eno1.device loaded active plugged P8P67 Deluxe Motherboard
sys-devices-pci0...-0000:00:1b.0-sound-card0.device loaded active plugged 7 Series/C210 Series Chipset Family High Definition
sys-devices-pci0...6-0000:07:00.0-net-wlp7s0.device loaded active plugged AR9485 Wireless Network Adapter
sys-devices-pci0...:0-0:0:0:0-block-sda-sda1.device loaded active plugged OCZ-VERTEX4
sys-devices-pci0...:0-0:0:0:0-block-sda-sda2.device loaded active plugged OCZ-VERTEX4
sys-devices-pci0...:0-0:0:0:0-block-sda-sda3.device loaded active plugged OCZ-VERTEX4
sys-devices-pci0...et0:0:0-0:0:0:0-block-sda.device loaded active plugged OCZ-VERTEX4
sys-devices-pci0...:0-1:0:0:0-block-sdb-sdb1.device loaded active plugged WDC_WD1001FALS-00J7B1
sys-devices-pci0...:0-1:0:0:0-block-sdb-sdb2.device loaded active plugged WDC_WD1001FALS-00J7B1
sys-devices-pci0...:0-1:0:0:0-block-sdb-sdb3.device loaded active plugged WDC_WD1001FALS-00J7B1
sys-devices-pci0...:0-1:0:0:0-block-sdb-sdb4.device loaded active plugged WDC_WD1001FALS-00J7B1
sys-devices-pci0...:0-1:0:0:0-block-sdb-sdb5.device loaded active plugged WDC_WD1001FALS-00J7B1
sys-devices-pci0...:0-1:0:0:0-block-sdb-sdb6.device loaded active plugged WDC_WD1001FALS-00J7B1
sys-devices-pci0...:0-1:0:0:0-block-sdb-sdb7.device loaded active plugged WDC_WD1001FALS-00J7B1
sys-devices-pci0...et1:0:0-1:0:0:0-block-sdb.device loaded active plugged WDC_WD1001FALS-00J7B1
sys-devices-pci0...et3:0:0-3:0:0:0-block-sr0.device loaded active plugged ATAPI_iHAS424_B
sys-devices-platform-serial8250-tty-ttyS0.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS0
sys-devices-platform-serial8250-tty-ttyS1.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS1
sys-devices-platform-serial8250-tty-ttyS2.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS2
sys-devices-platform-serial8250-tty-ttyS3.device loaded active plugged /sys/devices/platform/serial8250/tty/ttyS3
sys-module-configfs.device loaded active plugged /sys/module/configfs
sys-module-fuse.device loaded active plugged /sys/module/fuse
sys-subsystem-net-devices-eno1.device loaded active plugged P8P67 Deluxe Motherboard
sys-subsystem-net-devices-wlp7s0.device loaded active plugged AR9485 Wireless Network Adapter
-.mount loaded active mounted /
boot.mount loaded active mounted /boot
dev-hugepages.mount loaded active mounted Huge Pages File System
dev-mqueue.mount loaded active mounted POSIX Message Queue File System
home-facade-.cache.mount loaded active mounted /home/facade/.cache
mnt-data.mount loaded active mounted /mnt/data
run-user-1000-gvfs.mount loaded active mounted /run/user/1000/gvfs
scratch.mount loaded active mounted /scratch
sys-fs-fuse-connections.mount loaded active mounted FUSE Control File System
sys-kernel-config.mount loaded active mounted Configuration File System
sys-kernel-debug.mount loaded active mounted Debug File System
tmp.mount loaded active mounted Temporary Directory
var-cache.mount loaded active mounted /var/cache
systemd-ask-password-console.path loaded active waiting Dispatch Password Requests to Console Directory Watc
systemd-ask-password-wall.path loaded active waiting Forward Password Requests to Wall Directory Watch
cronie.service loaded active running Periodic Command Scheduler
dbus.service loaded active running D-Bus System Message Bus
fancontrol.service loaded active running Fan control daemon
[email protected] loaded active running Getty on tty1
gpm.service loaded active running Virtual console mouse server
lxdm.service loaded active running LXDE Display Manager
[email protected] loaded active exited A basic static ethernet connection using iproute
ntpd.service loaded active running Network Time Service
polkit.service loaded active running Authorization Manager
psd.service loaded active exited Profile-sync-daemon
rtkit-daemon.service loaded active running RealtimeKit Scheduling Policy Service
systemd-journald.service loaded active running Journal Service
systemd-logind.service loaded active running Login Service
systemd-modules-load.service loaded active exited Load Kernel Modules
systemd-remount-fs.service loaded active exited Remount Root and Kernel File Systems
systemd-sysctl.service loaded active exited Apply Kernel Variables
systemd-tmpfiles-setup.service loaded active exited Recreate Volatile Files and Directories
systemd-udev-trigger.service loaded active exited udev Coldplug all Devices
systemd-udevd.service loaded active running udev Kernel Device Manager
systemd-update-utmp.service loaded active exited Update UTMP about System Reboot/Shutdown
systemd-user-sessions.service loaded active exited Permit User Sessions
systemd-vconsole-setup.service loaded active exited Setup Virtual Console
udisks2.service loaded active running Disk Manager
ufw.service loaded active exited CLI Netfilter Manager
upower.service loaded active running Daemon for power management
cups.socket loaded active listening CUPS Printing Service Sockets
dbus.socket loaded active running D-Bus System Message Bus Socket
dmeventd.socket loaded active listening Device-mapper event daemon FIFOs
sshd.socket loaded active listening sshd.socket
systemd-initctl.socket loaded active listening /dev/initctl Compatibility Named Pipe
systemd-journald.socket loaded active running Journal Socket
systemd-shutdownd.socket loaded active listening Delayed Shutdown Socket
systemd-udevd-control.socket loaded active listening udev Control Socket
systemd-update-utmp.service loaded active exited Update UTMP about System Reboot/Shutdown
systemd-user-sessions.service loaded active exited Permit User Sessions
systemd-vconsole-setup.service loaded active exited Setup Virtual Console
udisks2.service loaded active running Disk Manager
ufw.service loaded active exited CLI Netfilter Manager
upower.service loaded active running Daemon for power management
cups.socket loaded active listening CUPS Printing Service Sockets
dbus.socket loaded active running D-Bus System Message Bus Socket
dmeventd.socket loaded active listening Device-mapper event daemon FIFOs
sshd.socket loaded active listening sshd.socket
systemd-initctl.socket loaded active listening /dev/initctl Compatibility Named Pipe
systemd-journald.socket loaded active running Journal Socket
systemd-shutdownd.socket loaded active listening Delayed Shutdown Socket
systemd-udevd-control.socket loaded active listening udev Control Socket
systemd-udevd-kernel.socket loaded active running udev Kernel Socket
basic.target loaded active active Basic System
cryptsetup.target loaded active active Encrypted Volumes
getty.target loaded active active Login Prompts
graphical.target loaded active active Graphical Interface
local-fs-pre.target loaded active active Local File Systems (Pre)
local-fs.target loaded active active Local File Systems
multi-user.target loaded active active Multi-User System
network.target loaded active active Network
paths.target loaded active active Paths
remote-fs.target loaded active active Remote File Systems
sockets.target loaded active active Sockets
sound.target loaded active active Sound Card
swap.target loaded active active Swap
sysinit.target loaded active active System Initialization
timers.target loaded active active Timers
psd-resync.timer loaded active waiting Timer for Profile-sync-daemon - 1Hour
systemd-tmpfiles-clean.timer loaded active waiting Daily Cleanup of Temporary Directories
And...
% systemctl list-unit-files
UNIT FILE STATE
proc-sys-fs-binfmt_misc.automount static
dev-hugepages.mount static
dev-mqueue.mount static
proc-fs-nfsd.mount static
proc-sys-fs-binfmt_misc.mount static
sys-fs-fuse-connections.mount static
sys-kernel-config.mount static
sys-kernel-debug.mount static
tmp.mount static
var-lib-nfs-rpc_pipefs.mount static
cups.path disabled
systemd-ask-password-console.path static
systemd-ask-password-wall.path static
alsa-restore.service static
alsa-state.service static
alsa-store.service static
arch32.service disabled
[email protected] disabled
avahi-daemon.service disabled
avahi-dnsconfd.service disabled
binfmt-support.service disabled
blkmapd.service disabled
canberra-system-bootup.service disabled
canberra-system-shutdown-reboot.service disabled
canberra-system-shutdown.service disabled
colord.service static
console-getty.service disabled
console-shell.service disabled
cronie.service enabled
cups-browsed.service disabled
cups.service disabled
cupsd.service disabled
dbus-org.freedesktop.hostname1.service static
dbus-org.freedesktop.locale1.service static
dbus-org.freedesktop.login1.service static
dbus-org.freedesktop.timedate1.service static
dbus.service static
debug-shell.service disabled
dhcpcd.service disabled
[email protected] disabled
display-manager.service enabled
distccd.service disabled
dkms.service disabled
dmeventd.service static
emergency.service static
fancontrol.service enabled
ftpd.service disabled
[email protected] enabled
[email protected] static
gpm.service enabled
hddtemp.service disabled
healthd.service disabled
initrd-cleanup.service static
initrd-parse-etc.service static
initrd-switch-root.service static
initrd-udevadm-cleanup-db.service static
ip6tables.service disabled
iptables.service disabled
irexec.service disabled
krb5-kadmind.service disabled
krb5-kdc.service disabled
krb5-kpropd.service disabled
[email protected] static
lirc.service disabled
lircm.service disabled
lm_sensors.service disabled
lxdm.service enabled
mcelog.service disabled
mpd.service disabled
[email protected] disabled
[email protected] disabled
netctl-sleep.service disabled
netctl.service disabled
[email protected] static
[email protected] static
[email protected] enabled
nfsd.service disabled
nmbd.service disabled
nscd.service disabled
ntpd.service enabled
ntpdate.service disabled
polkit.service static
psd-resync.service enabled
psd.service enabled
quotaon.service static
rescue.service static
rpc-gssd.service disabled
rpc-idmapd.service disabled
rpc-mountd.service disabled
rpc-statd.service disabled
rpc-svcgssd.service disabled
rpcbind.service disabled
rsyncd.service disabled
[email protected] static
rtkit-daemon.service disabled
samba.service disabled
sensord.service disabled
[email protected] static
smartd.service disabled
smbd.service disabled
[email protected] static
snmpd.service disabled
snmptrapd.service disabled
speech-dispatcherd.service disabled
sshd.service disabled
[email protected] static
sshdgenkeys.service static
svnserve.service disabled
[email protected] static
systemd-ask-password-console.service static
systemd-ask-password-wall.service static
systemd-binfmt.service static
systemd-fsck-root.service static
[email protected] static
systemd-halt.service static
systemd-hibernate.service static
systemd-hostnamed.service static
systemd-hybrid-sleep.service static
systemd-initctl.service static
systemd-journal-flush.service static
systemd-journal-gatewayd.service static
systemd-journald.service static
systemd-kexec.service static
systemd-localed.service static
systemd-logind.service static
systemd-modules-load.service static
[email protected] static
systemd-poweroff.service static
systemd-quotacheck.service static
systemd-random-seed-load.service static
systemd-random-seed-save.service static
systemd-readahead-collect.service disabled
systemd-readahead-done.service static
systemd-readahead-drop.service disabled
systemd-readahead-replay.service disabled
systemd-reboot.service static
systemd-remount-fs.service static
systemd-shutdownd.service static
systemd-suspend.service static
systemd-sysctl.service static
systemd-timedated.service static
systemd-tmpfiles-clean.service static
systemd-tmpfiles-setup-dev.service static
systemd-tmpfiles-setup.service static
systemd-udev-settle.service static
systemd-udev-trigger.service static
systemd-udevd.service static
systemd-update-utmp-runlevel.service static
systemd-update-utmp.service static
systemd-user-sessions.service static
systemd-vconsole-setup.service static
udisks.service disabled
udisks2.service static
ufw.service enabled
upower.service disabled
usbmuxd.service static
[email protected] disabled
uuidd.service static
vboxweb.service disabled
vncserver.service disabled
winbindd.service disabled
[email protected] disabled
[email protected] disabled
wpa_supplicant.service disabled
[email protected] disabled
avahi-daemon.socket disabled
cups.socket enabled
dbus.socket static
dmeventd.socket static
git-daemon.socket disabled
krb5-kpropd.socket disabled
rsyncd.socket disabled
smbd.socket disabled
sshd.socket enabled
swat.socket disabled
syslog.socket static
systemd-initctl.socket static
systemd-journal-gatewayd.socket disabled
systemd-journald.socket static
systemd-shutdownd.socket static
systemd-udevd-control.socket static
systemd-udevd-kernel.socket static
uuidd.socket disabled
basic.target static
bluetooth.target static
cryptsetup.target static
ctrl-alt-del.target disabled
default.target disabled
emergency.target static
final.target static
getty.target static
graphical.target disabled
halt.target disabled
hibernate.target static
hybrid-sleep.target static
initrd-fs.target static
initrd-root-fs.target static
initrd-switch-root.target static
initrd.target static
kexec.target disabled
local-fs-pre.target static
local-fs.target static
multi-user.target disabled
network-online.target static
network.target static
nss-lookup.target static
nss-user-lookup.target static
paths.target static
poweroff.target disabled
printer.target static
reboot.target disabled
remote-fs-pre.target static
remote-fs.target enabled
rescue.target disabled
rpcbind.target static
shutdown.target static
sigpwr.target static
sleep.target static
smartcard.target static
sockets.target static
sound.target static
suspend.target static
swap.target static
sysinit.target static
system-update.target static
time-sync.target static
timers.target static
umount.target static
psd-resync.timer static
systemd-readahead-done.timer static
systemd-tmpfiles-clean.timer static
231 unit files listed.
Last edited by graysky (2014-11-03 08:39:54)

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I've had this issue before, but it mentioned /usr/lib/sysctl.d/50-default.conf:
$ sudo journalctl --no-pager | grep sysrq
Aug 11 17:23:48 black systemd-sysctl[93]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 11 17:23:51 black systemd-sysctl[136]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 11 17:24:45 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 11 17:24:48 black systemd-sysctl[137]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 11 17:37:26 black systemd-sysctl[92]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 11 17:37:29 black systemd-sysctl[138]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 13 01:49:01 black systemd-sysctl[92]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 13 01:49:05 black systemd-sysctl[137]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 13 18:53:11 black systemd-sysctl[92]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 13 18:53:14 black systemd-sysctl[139]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 14 17:30:12 black systemd-sysctl[93]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 14 17:30:15 black systemd-sysctl[138]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 15 20:13:25 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 15 20:13:29 black systemd-sysctl[138]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 16 15:51:15 black systemd-sysctl[92]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 16 15:51:18 black systemd-sysctl[137]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 17 12:19:45 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 17 12:19:49 black systemd-sysctl[136]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 18 15:13:05 black systemd-sysctl[94]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 18 15:13:08 black systemd-sysctl[139]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 20 12:03:58 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 20 12:04:01 black systemd-sysctl[139]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 20 23:50:11 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 20 23:50:15 black systemd-sysctl[136]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 21 18:59:46 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 21 18:59:50 black systemd-sysctl[137]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 22 02:39:46 black systemd-sysctl[92]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 22 02:39:50 black systemd-sysctl[138]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 22 10:29:32 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 22 10:29:36 black systemd-sysctl[136]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 25 23:18:00 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 25 23:18:04 black systemd-sysctl[138]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 27 21:34:24 black systemd-sysctl[92]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 27 21:34:27 black systemd-sysctl[139]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 28 12:11:08 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 28 12:11:12 black systemd-sysctl[136]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 30 12:23:25 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 30 12:23:29 black systemd-sysctl[138]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 31 19:53:35 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Aug 31 19:53:39 black systemd-sysctl[136]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 01 07:26:50 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 01 07:26:54 black systemd-sysctl[135]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 02 19:53:12 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 02 19:53:16 black systemd-sysctl[136]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 03 12:36:10 black systemd-sysctl[91]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 03 12:36:14 black systemd-sysctl[136]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 04 13:50:08 black systemd-sysctl[92]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 04 13:50:12 black systemd-sysctl[136]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 05 12:28:40 black systemd-sysctl[90]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 05 12:28:44 black systemd-sysctl[136]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 07 09:01:16 black systemd-sysctl[95]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 07 09:01:20 black systemd-sysctl[141]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 09 18:59:31 black systemd-sysctl[94]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 09 18:59:34 black systemd-sysctl[139]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 10 19:11:48 black systemd-sysctl[95]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 10 19:11:52 black systemd-sysctl[140]: Duplicate assignment of kernel/sysrq in file '/usr/lib/sysctl.d/50-default.conf', ignoring.
Sep 17 22:53:39 black kernel: SysRq : This sysrq operation is disabled.
Sep 17 22:53:43 black kernel: SysRq : This sysrq operation is disabled.
Sep 17 22:54:00 black systemd-sysctl[96]: Overwriting earlier assignment of kernel/sysrq in file '/etc/sysctl.d/99-sysctl.conf'.
Sep 17 22:54:03 black systemd-sysctl[142]: Overwriting earlier assignment of kernel/sysrq in file '/etc/sysctl.d/99-sysctl.conf'.
Sep 17 22:54:49 black systemd-sysctl[96]: Overwriting earlier assignment of kernel/sysrq in file '/etc/sysctl.d/99-sysctl.conf'.
Sep 17 22:54:52 black systemd-sysctl[142]: Overwriting earlier assignment of kernel/sysrq in file '/etc/sysctl.d/99-sysctl.conf'.
$ cat /usr/lib/sysctl.d/50-default.conf
# This file is part of systemd.
# systemd is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
# See sysctl.d(5) and core(5) for for details.
# System Request functionality of the kernel (SYNC)
kernel.sysrq = 16
# Append the PID to the core filename
kernel.core_uses_pid = 1
# Source route verification
net.ipv4.conf.default.rp_filter = 1
# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0
# Enable hard and soft link protection
fs.protected_hardlinks = 1
fs.protected_symlinks = 1

Default Arch /etc/sysctl.conf

I looked in this file and found some interesting things that Arch devs appear to have made default, and I'd like to know why this is?
# Disable packet forwarding
net.ipv4.ip_forward = 0
# Disable the magic-sysrq key (console security issues)
kernel.sysrq = 0
# Enable TCP SYN Cookie Protection
net.ipv4.tcp_syncookies = 1
All three of these I'd like to hear the background on.
The SYSRQ key is disabled here? Wow, no wonder I've been having trouble getting it to work
Seriously though, security issues? Are we talking about these concerns? Do Arch devs not agree with the counter-point there?
Disable TCP SYN cookie protection -- isn't that a good thing? Does it slow some stuff down, then?
And then disabling packet forwarding... doesn't really hurt anyone who want that, and therefore would be able to figure out how to turn it on, but official word would be nice.
Last edited by Ranguvar (2009-12-31 03:27:34)

sysctl is a part of (UNIX) kernel, don't know one don't touch the other. Simple. Not to mention that all is available on the net. Wiki argument is not great, why not to run OS without security at all? There is no way to 100% protect box, so what is the point settting any protection at all?
Of course syncookies must be first enabled in kernel for sysctl command to work (by default in vanilla this is disabled), magic syskey can also be disabled in kernel and then whatever you do this option is gone.
sysctl gives easy way to control these features. It always amazes me that people have no idea about sysctl claiming at the same way that customization and security convinced them that linux is superior to windows.
default settings in sysctl.conf are remnants of good OBSD policy: everything is disabled, enable onlywhat you need. The opposite is windows policy: everything is enabled, disable what you don't need. Latter is much mode difficult to control.
I like sysctl because it gives so much control over disk performance (including fine tuning of fs), network, memory handling and obviously kernel based system hardening.
sysctl is so well described, than everybody can easily learn how to use it.
It's not equivalent to granting users power access, because you need physical access to the computer to use it.
magic sysrq is used for remote reboot for example (need to install ipt_sysrq).
On the other hand, disabling magic sysrq in sysctl.conf is not safest option because there is some periond of time before sysctl.conf is read so disabling in kernel config is better option from security standpoint

[root@test2 etc]# cat sysctl.conf

When i add some entry in
[root@test2 etc]# cat sysctl.conf
reboot the server or restart the file ........new in this need suggestions to make the change permanent.

assuming you are using Linux, hope that answer your question.
Using any text editor, create or edit the /etc/sysctl.conf file, and add or edit lines similar to the following:
Note:
Include lines only for the kernel parameter values that you want to change. For the semaphore parameters (kernel.sem), you must specify all four values. However, if any of the current values are larger than the recommended value, then specify the larger value.
kernel.shmall = 2097152
kernel.shmmax = 2147483648
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
fs.file-max = 65536
net.ipv4.ip_local_port_range = 1024 65000
net.core.rmem_default = 1048576
net.core.rmem_max = 1048576
net.core.wmem_default = 262144
net.core.wmem_max = 262144
By specifying the values in the /etc/sysctl.conf file, they persist when you restart the system.
On SUSE systems only, enter the following command to ensure that the system reads the /etc/sysctl.conf file when it restarts:
# /sbin/chkconfig boot.sysctl on

Help on 10g 64 bit --Sizing SGA and sysctl.conf

Dear Sir,
I have an oracle10g installed on a 64 bit OS and want to allocate 8GB to SGA and want to confirm if i am using the right settings
My sysctl.conf settings are :
cat /etc/sysctl.conf
# Kernel sysctl configuration file for Red Hat Linux
# For binary values, 0 is disabled, 1 is enabled. See sysctl(8) and
# sysctl.conf(5) for more details.
# Controls IP packet forwarding
net.ipv4.ip_forward = 0
# Controls source route verification
net.ipv4.conf.default.rp_filter = 1
# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0
# Controls the System Request debugging functionality of the kernel
kernel.sysrq = 0
# Controls whether core dumps will append the PID to the core filename
# Useful for debugging multi-threaded applications
kernel.core_uses_pid = 1
# Controls the use of TCP syncookies
net.ipv4.tcp_syncookies = 1
# Controls the maximum size of a message, in bytes
kernel.msgmnb = 65536
# Controls the default maxmimum size of a mesage queue
kernel.msgmax = 65536
kernel.shmmax = 8589934592
kernel.shmmni = 4096
kernel.shmall = 2097152
kernel.sem = 3000 32000 100 128
net.core.rmem_default=262144
net.core.rmem_max=262144
net.core.wmem_default=262144
net.core.wmem_max=262144
My init Settings are :
*._DB_BLOCK_LRU_LATCHES=16
*._spin_count=7000
*.archive_lag_target=1800
*.audit_sys_operations=TRUE
*.BACKGROUND_DUMP_DEST='/redf/DB/dbf/dump'
*.circuits=10000
*.COMPATIBLE='10.2.0.4'
*.CONTROL_FILES='/redf/DB/dbf/cntl1/DB_cntl1_01.ctl','/redf/DB/dbf/cntl2/DB_cntl2_02.ctl','/redf/DB/dbf/cntl3/DB_cntl3_03.ctl'
*.CORE_DUMP_DEST='/redf/DB/dbf/dump'
*.cursor_sharing='FORCE'
*.DB_BLOCK_SIZE=8192
*.DB_CACHE_SIZE=1024M
*.db_file_multiblock_read_count=64
*.db_file_name_convert='/redf/DB/dbf','/redf/DB/dbf'
*.DB_NAME='DB'
*.db_writer_processes=8
*.dispatchers='(PROTOCOL=TCP)(DISPATCHERS=10)'
*.FAST_START_MTTR_TARGET=300
*.INSTANCE_NAME='DB'
*.JAVA_POOL_SIZE=64M
*.JOB_QUEUE_PROCESSES=1
*.large_pool_size=150M
*.LOCAL_LISTENER='(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=XX.XX.XX.XXX)(PORT=1521)))'
*.LOG_ARCHIVE_DEST_1='LOCATION=/redf/DB/arch'
*.LOG_ARCHIVE_DEST_2='LOCATION=/orabackup/redf/DB/arch_new'
*.log_archive_dest_state_2='ENABLE'
*.log_archive_format='DB%t_%r_%s.arc'
*.log_archive_max_processes=2
*.log_archive_min_succeed_dest=1
*.LOG_ARCHIVE_START=TRUE
*.log_buffer=50000000
*.MAX_DISPATCHERS=40
*.max_shared_servers=40
*.O7_DICTIONARY_ACCESSIBILITY=FALSE
*.open_cursors=10000
*.optimizer_index_cost_adj=20
*.parallel_adaptive_multi_user=TRUE
*.parallel_automatic_tuning=TRUE
*.parallel_max_servers=20
*.parallel_min_servers=2
*.processes=4000
*.QUERY_REWRITE_ENABLED='TRUE'
*.QUERY_REWRITE_INTEGRITY='ENFORCED'
*.recovery_parallelism=5
*.recyclebin='OFF'
*.remote_archive_enable='TRUE'
*.REMOTE_LOGIN_PASSWORDFILE='EXCLUSIVE'
*.remote_os_authent=FALSE
*.resource_limit=TRUE
*.session_cached_cursors=200
*.sessions=4000
*.SGA_MAX_SIZE=8000M
*.SGA_TARGET=6500M
*.shared_pool_size=1024M
*.shared_servers=10
*.sort_area_size=10485760
*.sql92_security=TRUE
*.standby_archive_dest='/redf/DB/arch'
*.standby_file_management='AUTO'
*.statistics_level='TYPICAL'
*.timed_statistics=TRUE
*.UNDO_MANAGEMENT='AUTO'
*.undo_retention=1800
*.undo_tablespace='UNDOTBS'
*.USER_DUMP_DEST='/redf/DB/dbf/dump'
Want to confirm is this a proper tuend settings as per memory provided ?
I am aware that it also depends on my appication behaviour , but i just want to check whether the above settings would suffice for a 16GB RAM machine and 64 bit oracle10g
Also let me know if any other setttings apart from this are required , i choose to use SGA Target .Further my application is read intensive . Your suggestions will be highly appreciated.
Thanx

Hi,
I suggest you to increase the value kernel.shmmax = 8589934592 of this parameter in sysctl.conf to kernel.shmmax = 1288490188
Later if you want to increase the size of SGA then you need to modify the kernel.shmmax = 8589934592 value. In general practice we keep kernel.shmmax value little greater then the value of SGA.
Refer MOS tech note:
*ORA-27102 Database Will Not Start With SHMMAX Set To 8589934592 (8GB) [ID 461519.1]*
*Linux Big SGA, Large Memory, VLM - White Paper [ID 260152.1]*
thanks,
X A H E E R
Edited by: ora_tech on Dec 26, 2010 10:14 AM

10.10.1 I use sysctl.conf to increased shared memory. 10.10.1 does not read sysctl.conf anymore

I need to increase shared memory. In 10.10 is use /etc/sysctl.conf with a line kern.sysv.shmmax=16777216 and this works. Also in 10.9. But in 10.10.1 shared memory can no longer be increased from the default 4194304 by this means.
The question is simple: how in 10.10.1 does one increase kern.sysv.shmmax in a way that survives a re-boot

I have the same problem on my windows 2003 server but the
thing is that I have not been able to get the same error on any
other machine including a windows 2003 I installed on VMWare on the
same machine. I have narrowed down to where in the encoder this
happens. The encoder uses page file backed file maps to register
session information. The call to MapViewOfFileEx method of the
Win32 API fails with the "access denied" error. Whatever it is,
it's due to some defect in the Windows installation I have because
I do not get that message on any other windows installation even
the ones I do with the same windows CD !
I am still trying to find out what the defect might be but I
thought you should know it's got nothing to do with you Windows
make and model...it happens for me on 2k3 and for you on XP...so
you should looke elsewhere..

Unable to find sysctl.conf

Hi,
I want to install oracle s/w for my production server. before installing oracle i want to set kernel parameters in /etc/sysctl.conf .i logined as root user but i couldn't able to fine sysctl.conf file on server..
Edited by: 920033 on Apr 12, 2012 7:54 AM

920033 wrote:
Hi,
I want to install oracle s/w for my production server. before installing oracle i want to set kernel parameters in /etc/sysctl.conf .i logined as root user but i couldn't able to fine sysctl.conf file on server..
Edited by: 920033 on Apr 12, 2012 7:54 AM
bcm@bcm-laptop:~$ ls -l /etc/sysctl.conf
-rw-r--r-- 1 root root 2364 2010-05-07 09:48 /etc/sysctl.conf
bcm@bcm-laptop:~$

[solved]how to stop /etc/resolv.conf keeps being overwritten ???

no matter how many times to change the content, it keeps like that:
# Generated by dhcpcd from eth0
# /etc/resolv.conf.head can replace this line
nameserver 192.168.8.1
# /etc/resolv.conf.tail can replace this line
so i can't add nameserver in it
Last edited by tempo (2010-01-14 15:01:35)

The clue is in the message, use a file called resolv.conf.head to add a nameserver to the top and resolv.conf.tail to add it to the bottom.
It's being overwritten because you are using dhcpcd to auto configure your network settings.
Last edited by Meyithi (2010-01-14 13:03:43)

Settings in sysctl.conf not re-loaded on reboot - kernel.printk

My default kernel.printk values are 15 1 1 7, so I get bunch of kernel messages on all tty shells.
So to fix this, I changed default kernel.printk values from 15 1 1 7 to 4 1 1 7 by modifying line in sysctl.conf > "kernel.prink 4 1 1 7"
When I do sysctl -p, changes get applied and excess kernel message go away. However if I reboot, kernel.prink goes back to 15 1 1 7 and I have to run sysctl -p again.

I've seen this issue reported in a few other threads before (sysctl.conf settings apparently not being applied during boot). Not really sure what's causing it; but you could workaround the issue by adding "sysctl -p" to your /etc/rc.local. Not a structural fix obviously, but it will get rid of the issue.

[SOLVED] Changed an option in /etc/updatedb.conf

Hello all,
I started using locate to search my files. However, it never showed files in my /home directory which is, obviously, the directory I search most. Running updatedb --debug-pruning I found out that it didn't add /home to the database because it's an "autofs" filetype:
┌─[jente @ lappy ~] 23:54:27
└─■ sudo updatedb --debug-pruning
`/home' (32 on 18) is `/' of `systemd-1' (0:27), type `autofs'
Skipping `/home': in prunefs
So, I edited /etc/updatedb.conf and removed autofs from the PRUNEFS line. I never found any documentation on this and thus, I don't know if this is the correct way of solving this. Hence this post; I would just like to get some feedback on whether or not I fixed this the right way.
Thanks in advance, guys!
Last edited by Unia (2012-12-15 13:45:36)

Unia wrote:
Mr.Elendig wrote:Another way would be to add your /home to fstab instead.
Hey! Thanks for your input. My /home is actually already there:
# /etc/fstab: static file system information
# <file system> <dir> <type> <options> <dump> <pass>
tmpfs /tmp tmpfs nodev,nosuid 0 0
# /dev/sda1
UUID=60eb73f7-635c-4b3e-9d6a-8bb49aee739a / ext4 rw,relatime 0 1
# /dev/sda2 LABEL=home
UUID=4470b151-db99-4586-a652-398e0e8995cb /home ext4 rw,relatime,noauto,x-systemd.automount 0 2
If your /home is on an internal disk, why use automount?

[SOLVED] How to restore kernel image after wrong /etc/mkinitcpio.conf

I wanted to learn a bit more about the kernel and boot, and I'm afraid I cannot start up my ArchLinux anymore.
I updated the /etc/mkinitcpio.conf to make the boot faster (with this reference: http://kmandla.wordpress.com/2007/01/30 … initcpio/) and executed #mkinitcpio -p kernel26
I thought that if there was any problem, I could start up with the "fallback image". Certainly, there was a problem (probably I didn´t loaded all the modules required) and when I tried the fallback image, I experimented the same problem:
Root device '/dev/disk/by-uuid/...' doesn´t exist
ramfs$
In fact, both images are the same (or at least they have the same size)
I tried the ArchLinux liveCD to recover my system. There's no recovery service, so I started up the CD-ROM, mounted my ArchLinux partitions, generated the images and copied into the /boot of my Archlinux partitions. But the same problem is still there.
What could I do to fix it?
Thank you in advance
Last edited by jjjaime (2009-05-10 15:45:45)

Thank you. I follow your instructions and it worked (perhaps it would be simpler with a "#pacman -Sy kernel26"). I didn't know the command chroot and it's really interesting.
red_erik wrote:
I have a similar problem, (read more in this thread), and I solve it by booting off the Live CD, and doing the following:
(replace sda1 with your / partition)
cd /
mount -t ext3 /dev/sda1 /mnt
mount -t proc proc /mnt/proc
mount -t sysfs sys /mnt/sys
mount -o bind /dev /mnt/dev
chroot /mnt /bin/bash
mkinitcpio -p kernel26
after that, I exit chroot, unmount all of my partitions and reboot...:
cd /
umount -a
exit
cd /
umount -a
reboot
hope this helps...

[solved]Delay mySQL startup by 30 secs in /etc/rc.conf

Basically I use wpa_supplicant and it takes a a bit to connect, by the time /etc/rc.conf gets to the mysql startup service, mySQL cannot bind to my servers address,
This is because wpa_supplicant probably hasn't got an IP address yet, so mySQL fails to start at bootup every time, however right after the boot I can log in and manually boot it just fine.
Any Ideas? Maybe delay the mysql by 30-40 seconds at boot? Anyone know how?
Last edited by kr1zmo (2010-07-05 23:57:10)

itsbrad212 wrote:
You could put:
/etc/rc.d/mysqld start
in /etc/rc.local
Thanks for the reply but I solved this by removing the @ before netprofiles, so that wpa_supplicant doesnt startup in the background, therefor everything else waits until wpa_supplicant is connected before it boots.
Last edited by kr1zmo (2010-07-05 23:59:58)

Settings in /etc/sysctl.conf overwritten [SOLVED]

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