OPEN SSH

SSH

--> Pkg     -openssh

    Daemon  -sshd

    Portnum -22

    Files   -/etc/ssh/sshd_config

            .ssh/*

---> vim /etc/ssh/sshd_config

1. line 13  -> change port num.

   Port  53

   service sshd restart

   client connecting to your machine should connect giving like this

   ssh  -p 53  <server ip>  ,Only then it connects.

2. line 37   -> Allow/stop user to ssh

   AllowUsers  u1

   DenyUsers   u2

   service sshd restart

   This stops a client to connect as u2 and can connect as only u1 user.

3. line 37   -> Allow/stop user to ssh

   AllowGroups  asia

   DenyGroups   america

   service sshd restart

   This stops a client to connect as any members of america, and can connect

   as any member os america.

4. line 38  -> Login grace time.

   LoginGraceTime 1m  

   service sshd restart

   Once you connect to sshserver, you haf to provide passsword within a min,

   or connection fails.

5. line 39  -> Root login allowed/not-allowed

   PermitRootLogin no

   service sshd restart

   This stops a client to ssh as root user,anb can connect as normal user only

6. line 41  -> Password prompts

   MaxAuthTries 1

   service sshd restart

   Password is prompted only twice within which he has to give right password

   to authenticate.

7. line 96  -> Stop Gui Access

   X11Forwarding no

   service sshd restart

   Thou the client connects to your server using ssh -X <server.ip>, they

   wont be able to connect to GUI of Server

8.  Generating  Public/Private key

--> To generate the key     ->Generates id_dsa,id_dsa.pub files under .ssh dir

    ssh-keygen  -t   dsa

--> To copy key to client machine   ->copies id_dsa to .ssh of clients machine

    ssh-copy-id  -i   /root/.ssh/id_dsa    <clients.ip>