SSH keys

1. on my laptop as common user peter

 $ ssh-keygen -t dsa
 

then i shall have in /home/peter/.ssh a pair of keys (public key: id_dsa and private key: id_dsa.pub)

1. now on romi

 #mkdir peter/.ssh
 

copy my public key here with the name authorized_keys

I can login romi safer with my ssh keys

//login for the first time I need to type 111111 to active to key

//but if I need to login in other machines I still need the former passwd: peter1983

when I reinstall my local OS, I need to do the above 3 step again.

but when I am trying to copy sth form romi to my local machine, I see warning related to romi: ./ssh/knownhost

the solution is simply deleting this file, it will be created again automatically

HOW to open ssh ports in ubuntu

$ sudo apt-get install openssh-server

$sudo /etc/init.d/networking restart

ON fedora or asianux

#service sshd start/status/stopo
#vim /etc/ssh/sshd_config

how to login 155 conviniently

1. on ubuntu as root user, issue

 $ssh-keygen
 

1. copy the pub key to 155 as its authorized_keys
2. on ubuntu

 $vim /etc/hosts
 

add

 10.1.0,155    test
 

1. then we can login with

 $ssh test
 without using passwd
 

starting ssh on Asianux

1. vim /etc/ssh/sshd_config change the correaponding line into

 #PermitRootLogin no
 PermitRootLogin yes
 

and do this

 service sshd start
 chkconfig --level 345 sshd on ----------set boot time start
 

1. done

Problem

when I try to ssh 67, which is the new vmware machine on 73.

I see this

[root@dhcp25 ~]# ssh 10.1.0.56
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!

1. on my local machine
2. vim /root/.ssh/known_hosts
3. delete the key for fomer 67 machine.(it was for former xen machine)——it just conflicts with the new 67 machine.