Fix slow connections to SSH server

My development ubuntu was too slow when connecting through ssh. To make this faster, I added the following option on sshd_config.

sudo vi /etc/ssh/sshd_config

UseDNS no

Before using this option, I thought that Ssh.Net library caused this with its insufficient ability but it's my mistake.

There might be more options to consider this. 

GSSAPIAuthentication no

# ipv4 only
AddressFamily inet

In my case, "UseDNS no" satisfied me.

From

• http://unsharptech.com/2009/04/11/fix-slow-connections-to-ubuntu-ssh-servers/
• http://cosmicb.no/2013/09/11/slow-delayed-hanging-ssh-connect-from-one-centos-6-to-an-other-centos-6/