I want to restrict both normal users and root user inside LXD container “hypervisor” from viewing and using dmesg command output. How do I prevent non-root (unprivileged) Linux users from viewing the Linux kernel’s log buffer? Can Linux prevent unprivileged users from viewing dmesg command output?
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I am new Linux system user. How do I reload all sysctl variables without rebooting my server?
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I am a new FreeBSD Unix user. How do I get the temperature of an Intel or AMD processor (CPU) in FreeBSD using command line option? Is there a command line option for determining CPU temperature on FreeBSD Unix operating system version 9.x/10.x/11.x/12.x/13.x?
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I run a web-server, and I would like to log packets with un-routable source addresses on Linux operating system. How can I log spoofed packets on a Debian, Ubuntu, CentOS/RHEL or any Linux based server? How can I log a Martian packet (packet from Mars) on Linux operating systems?
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I am trying to set exec-shield protection on Linux as described here but getting the following error on Ubuntu Linux server version 12.04 LTS:

sysctl -w kernel.exec-shield=1
error: “kernel.exec-shield” is an unknown key

How do I fix this problem and make sure exec-shield buffer overflow protection security feature turned on Ubuntu Linux?
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I am under DoS attack. My cloud based server hosting company asked me to enable TCP SYN cookie protection to save my domain from SYN Attack. How do I turn on TCP Syn cookie protection under Ubuntu or CentOS Linux based server?
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