Install packages necessary for building source package

Ubuntu, Debian

apt-get build-dep <package>

If you got error

E: You must put some 'source' URIs in your sources.list

You have to enable deb-src in /etc/apt/sources.list.
Uncomment the deb-src line of the URLs which is enabled in deb line.

deb xenial main restricted
deb-src xenial main restricted


yum-builddep <package>

How to make sure that password authentication is disabled on SSH

After I have disabled password authentication on SSH, I want to attempt to connect with password authentication so that I confirm that password authentication is certainly disabled.

With -o option set PreferredAuthentications to password.

$ ssh -o PreferredAuthentications=password
Permission denied (publickey,gssapi-keyex,gssapi-with-mic).

If you see "Permission denied", it's OK.