Linux Ask! is a Q & A web site specific for Linux related questions. Questions are collected, answered and audited by experienced Linux users.
How do I set up a firewall under Linux?
Answer:
In Linux, IPTables is the default firewall for kernels 2.4 and above.
IPTables is quite a complicated software which cannot be explained in just a few words, please refer to a more comprehensive howto:
How do I use GPG?
Answer:
The following tutorial are recommended to learn more about GPG:
The GNU Privacy Guard HandBook: http://www.gnupg.org/gph/en/manual.html
What is security?
Answer:
Security, in a nutshell, is ensuring the Confidentiality, Integrity, and Availability of your systems and network.
Why am I seeing "-- Mark --" in my syslog?
Answer:
This is a timestamp which is automatically generated by syslogd, and is syslogd's way of stating that it has nothing to report. The default interval between two -- MARK -- lines is 20 minutes.
This can be changed by locating the syslodg startup script, and changing the parmeter after the "-m" option to suit your needs. To disable these timestamps completely, set "-m" to 0. For more information, type "man syslogd".
How to turn off SELinux?
Answer: (pick either one)
1. Change the run-time configuration (won't take effect when you reboot)
# sestatus informs you of the two permission mode statuses,
# the current mode in runtime and the mode from the config
# file referenced during boot:
sestatus | grep -i mode
Current mode: enforcing
Mode from config file: enforcing
# Changing the runtime enforcement doesn't effect the
# boot time configuration:
setenforce 1
sestatus | grep -i mode
Current mode: permissive
Mode from config file: enforcing
2. Turn off SELinux permanently, use the following command
system-config-securitylevel
