RHEL: Displaying/setting kernel parameters - ’sysctl’

RHEL: Displaying/setting kernel parameters - 'sysctl'

# Tested on RHEL 6 & 7

# Setting kernel parameters is a fairly straightforward task. If we check the file
# /etc/sysctl.conf, we will see several attributes with their appropriate values, these are
# the values applied at startup. This file can be edited directly with a text editor, then
# the values reloaded by executing 'sysctl -p'.
# On RHEL 7, default settings are in /usr/lib/sysctl.d/00-system.conf. These default
# settings may be overridden by entering new settings in /etc/sysctl.conf or in an
# /etc/sysctl.d/<name>.conf file.

# These values can also be changed at runtime by modifying the values under /proc/sys.
# For instance, attribute named net.ipv4.ip_forward can be viewed or modified as
# /proc/sys/net/ipv4/ip_forward.

# To view the running value, run:

cat /proc/sys/net/ipv4/ip_forward

# To change the running value, run:

echo 1 > /proc/sys/net/ipv4/ip_forward

# The kernel attributes and values available to change can be found by either browsing the
# /proc/sys folders, or by running 'sysctl -a':

/sbin/sysctl -a | grep net.ipv4.ip_forward

# Lastly, values can be hot modified by running 'sysctl -w' command:

/sbin/sysctl -w

# To fix this change, insert a new line with the parameter in file /etc/sysctl.conf.

# Load in settings from the file specified or /etc/sysctl.conf if none given:

/sbin/sysctl -p [/etc/sysctl.conf]
0 (0)
Article Rating (No Votes)
Rate this article
There are no attachments for this article.
There are no comments for this article. Be the first to post a comment.
Full Name
Email Address
Security Code Security Code
Related Articles RSS Feed
How to convert RAW image to VDI and otherwise
Viewed 14615 times since Wed, Oct 3, 2018
LVM: Move allocated PE between Physical Volumes
Viewed 3611 times since Sat, Jun 2, 2018
Index » Community Contributions » System encryption using LUKS and GPG encrypted keys for arch linux
Viewed 2746 times since Fri, Jul 13, 2018
Tips to Solve Linux & Unix Systems Hard Disk Problems
Viewed 3897 times since Fri, May 15, 2020
Oracle Linux 7 – How to audit changes to a trusted file such as /etc/passwd or /etc/shadow
Viewed 2702 times since Wed, Jul 25, 2018
A Quick and Practical Reference for tcpdump
Viewed 12170 times since Fri, Jul 27, 2018
Install OpenVPN On CentOS / RHEL 7
Viewed 2783 times since Fri, May 15, 2020
RHEL7: Configure automatic updates.
Viewed 1661 times since Wed, Oct 17, 2018
Migrate a Linux System from Red Hat Enterprise to CentOS
Viewed 10073 times since Fri, May 15, 2020
Netcat shell zabezpieczony hasłem
Viewed 1956 times since Thu, May 24, 2018