Terminal command with sudo takes a long time

I noticed that the terminal recently becomes too slow when I execute a command that needs my password. It takes some seconds to display [sudo] password for ...

I'm using Dell XPS developer edition (i7,8G RAM) with Ubuntu 13.04 64bit.

Hi I found this answer on another question - The problem is if your hostname is not in your hosts file.

basically, type "hostname" in your terminal. That will tell you what your hostname is.

Next, type:

sudo nano /etc/hosts

and add:

127.0.0.1 yourhostname

then save - and you are done! Sudo should be fast now!

When you change your systems name in Gnome (The part that is displayed in the terminal after the @; e.g. tobias@laptop to tobias@newlaptop you might need to update your /etc/hosts:

127.0.1.1 laptop

needs to be changed to

127.0.1.1 newlaptop

If you get it right sudo should work without delay immediately after saving this setting.

Answer 1
Confirmed @Paul Preibisch answer for those who want more detailed answer

I had this issue for a long time and all I did was to run

hostnamectl | grep -i "static hostname"

this will show you your hostname then copy the value and edit your hosts

sudo vim /etc/hosts

and add 127.0.0.1 yourHostName to it
also in some distros 127.0.1.1 yourHostName should be replaced

Answer 2
Please note that in many cases the answer 1 will solve your problem if it didn't you have to check your sudo log which in debian based distros is under
/var/log/auth.log
so you can watch your sudo log with tail command
sudo tail -f -n 100 /var/log/auth.log
then open another terminal and run a sudo command like:
sudo ls /
go back to your first terminal and read the log, in my case the problem was due to pam_krb5 authentication failure the log was:
sudo: pam_krb5(sudo:auth): authentication failure;
after I removed it sudo command worked instantly...

Thanks to @gdm for giving the clue...