Daily IT pill

Is there any tool i n Linux to dump the system memory?

Yes, you can grab Linux Memory Grabber from GitHub instead of trying to read directly to /dev/mem or develop yourself a program. Keep in mind that is impossible to read all RAM and not modify at least a tiny part of it while doing so.

Daily tip

How do I disable IPv6 permanently on all interfaces?

Open /etc/sysctl.conf with a text editor, and add the following lines.

#to disable IPv6 on all interfaces system wide

net.ipv6.conf.all.disable_ipv6 = 1

Then run
$ sudo sysctl -p /etc/sysctl.conf

Daily tip

How to create a password which can be used to grant access to some areas in your server?

With the Apache utility htpasswd like in the example below

htpasswd -c /usr/local/apache/passwd/passwords rbowen

Note that the password file must be outside the DocumentRoot FOlder and therefore outside from Internet reach, for obvious reasons.

Daily tip

Is there an alternative to sudo or setuid?

Yes: capabilities. Look at:
http://man7.org/linux/man-pages/man7/capabilities.7.html