one command SSH setup

 
		luser@linuxbox4 [/home/luser/.ssh]
		------------------------------------------------
		--> ssh-keygen -t rsa -N '' -f id_rsa ; \
		cp id_rsa.pub id_rsa.lnxb4  ; \
		scp id_rsa.lnxb4 linuxbox:/home/luser/.ssh/ ; \
		ssh linuxbox "cp /home/luser/.ssh/authorized_keys \
		/home/luser/.ssh/authorized_keys-8oct2015 ; \
		cat /home/luser/.ssh/id_rsa.lnxb4 >> \
		/home/luser/.ssh/authorized_keys ; \
		scp linuxbox:/home/luser/.ssh/id_rsa.lnxb . ; \
		cp authorized_keys authorized_keys-8oct2015 ; \
		cat id_rsa.lnxb >> authorized_keys ; \
		ssh linuxbox w"
		
 SUBSTITUTE:  
	luser for your userid
	lnxb4 for your client hostname
	lnxb for your remote hostname

 
 The Single command to CREATE local KEY:   
	 ssh-keygen -t rsa -N '' -f id_rsa

 NOTES:
# luser = local user
# lnxb  = linuxbox
# lnxb4 = linuxbox4
 
 
summary of steps combined above 
#################################################
username:  luser (local user)
clientname:  linuxbox4  (abbreviated lnxb4)
remoteclient:  linuxbox  (abbreviated lnxb)
 
setting up passwordless connection between both systems
from linuxbox4 in /home/luser/.ssh  - a new system on the
network of other linuxboxes.
 
#################################################
#   establish rsa public key:
 
1)  ssh-keygen -t rsa -N '' -f id_rsa
 
#################################################
#  make a copy for public sharing:
 
2) cp id_rsa.pub id_rsa.lnxb4
 
#################################################
# THIS IS WHERE ALL THE MAGIC HAPPENS:
#  copy public key to main system,
# then back up authorized keys there,
# then add lnxb4 public key to authorized keys,
# then copy main system's public key back to lnxb4,
# then back up local authorized keys,
# then add main system's public key to local authorized keys
# you will need to enter luser's passwd 2 or 3 times during this process
 
		3) scp id_rsa.lnxb4 linuxbox:/home/luser/.ssh/ ; \ # copy public key
		ssh linuxbox "cp /home/luser/.ssh/authorized_keys \	  # backup remote autorhorized keys pt1
		/home/luser/.ssh/authorized_keys-8oct2015 ; \	      # backup remote autorhorized keys pt2
		cat /home/luser/.ssh/id_rsa.lnxb4 >> \			  # add your local key to remote host pt1
		/home/luser/.ssh/authorized_keys ; \			  # add your local key to remote host pt2
		scp linuxbox:/home/luser/.ssh/id_rsa.lnxb . ; \	      # copy remote key to your system
		cp authorized_keys authorized_keys-8oct2015 ; \		  # backup your local authorized keys
		cat id_rsa.lnxb >> authorized_keys "			  # append your local authorized keys with remote key 
 
#################################################
#  test connection from linuxbox4
 
4) ssh linuxbox
#  (you should be on linuxbox)
  ssh linuxbox4 w
#  (you should be seeing info from linuxbox4)
   exit
#  (you should be back on linuxbox4
# resume normal operations, you have a bi-directional passwordless connection.
 
 
#################################################
------------------------------------------------
luser@system [/home/luser/.ssh]
------------------------------------------------
--> ssh-keygen -t rsa -N '' -f id_rsa
Generating public/private rsa key pair.
Your identification has been saved in id_rsa.
Your public key has been saved in id_rsa.pub.
The key fingerprint is:
2b:2b:dd:e7:8d:12:8b:53:02:4f:be:9e:ce:7e:c0:2f luser@system
The key's randomart image is:
+--[ RSA 2048]----+
|      ...        |
|       +. .      |
|        o+       |
|       .oo.      |
|       .So       |
|       oo..      |
|      . +o .     |
|       = .+ .o   |
|      o.o..=E .  |
+-----------------+
 
------------------------------------------------
luser@linuxbox4 [/home/luser/.ssh]
------------------------------------------------
--> scp id_rsa.lnxb4 linuxbox:/home/luser/.ssh/ ; \
ssh linuxbox "cp /home/luser/.ssh/authorized_keys \
/home/luser/.ssh/authorized_keys-8oct2015 ; \
cat /home/luser/.ssh/id_rsa.lnxb4 >> \
/home/luser/.ssh/authorized_keys ; \
scp linuxbox:/home/luser/.ssh/id_rsa.lnxb . ; \
cp authorized_keys authorized_keys-8oct2015 ; \
cat id_rsa.lnxb >> authorized_keys ; \
ssh linuxbox w"
 
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