Find active SSH servers w/ ssh keys on LAN

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Top Forums Shell Programming and Scripting Find active SSH servers w/ ssh keys on LAN
# 8  
Old 11-02-2018
For a reason that I ignore, it seems like when doing:
echo $users
echo $ssh_keys
echo $hosts_known

It's giving the following output all on the same line for each echo instead of let's say, 1 user per line which is why I am having issue right now!

See output result:

root sirius postgres
/home/sirius/.ssh/id_rsa /var/lib/postgresql/.ssh/id_rsa /var/lib/postgresql/.ssh/

When it should be something like:


Any idea how I could fix this ?

Thanks for your help !

Last edited by syrius; 11-02-2018 at 11:10 PM.. Reason: forgot a word
# 9  
Old 11-05-2018
I'm assuming that you have the same code posted earlier:-
users=$(cat cutted.bash_users)
cat ssh-keys.txt | awk '{print $9}' > cutted.ssh_keys.txt
ssh_keys=$(cat cutted.ssh_keys.txt)

if ssh -l $users -i $ssh_keys $hosts_known -o BatchMode=yes -o ConnectTimeout=5
then echo $users:$hosts_known:$ssh_keys SUCCESS >> results.txt
echo $users:$hosts_known:$ssh_keys FAILED >> not-active.txt

Your command starting if ssh -l $users ...... will expand to include ALL the values of $users so you would end up with a command line like:-
if ssh -l root sirius postgres -i /home/sirius/.ssh/id_rsa /var/lib/postgresql/.ssh/id_rsa /var/lib/postgresql/.ssh/ -o BatchMode=yes -o ConnectTimeout=5

....which is an awful mess. This will try to login to server sirius with user account root (no key provided) and run the command postgres -i /home/sirius/.ssh/id_rsa /var/lib/postgresql/.ssh/id_rsa /var/lib/postgresql/.ssh/ -o BatchMode=yes -o ConnectTimeout=5

Do you actually want to loop round and try all the combinations perhaps? If so, try something like:-
for one_user in $users
   for one_sshkey in $ssh_keys
      for one_host in $known_hosts
         if ssh -l $one_user -i $one_key -o BatchMode=yes -o ConnectTimeout=5 $one_host 
            echo $one_user:$one_key:$one_host >> results.txt
            echo $one_user:$one_key:$one_host FAILED >> not-active.txt

Does that get you any nearer? note that I put the target host at the end so that all the options will be used. There will very likely be lots of failures as you try all the combinations.

As another note, there is no point trying to login with a public key.

I hope that this helps,
This User Gave Thanks to rbatte1 For This Post:
# 10  
Old 11-06-2018
Great, I believe this should do the trick very well, I will test it tomorrow morning. I have 2 questions;

1) Why some ':' at the beginning?
2) Doesn't the 'one_user' 'one_host' 'one_sshkey' variables needs to be defined before using them? like one_user = $(...)

# 11  
Old 11-06-2018
Originally Posted by syrius
Doesn't the 'one_user' 'one_host' 'one_sshkey' variables needs to be defined before using them?
The loops define them. for x in a b c d e defines the $x variable for example.
# 12  
Old 11-06-2018
Originally Posted by syrius
. . .
1) Why some ':' at the beginning?
. . .

Just guessing - some sort of vertical ellipsis?
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