[solved]Pimatic ssh rules are giving error Host key verification failed.

---

I have set up ssh via lan. Then wanted to use ssh via wifi and it throws now an error.

Command Line ssh commands are working. But via Pimatic it gives an error: Host key verification failed.

For example:
Using commandline works:

ssh ssh pi@192.168.1.201 sudo reboot

Using pimatic rule it fails:

execute "ssh pi@192.168.1.201 'sudo reboot'"

And gives errors:

Error on evaluation of rule condition of rule sound2: undefined
error executing an action: undefined
error [pimatic-shell-execute]: [ShellActionHandler] Error: Command execution failed with exit code 255 (Error: Command failed: Host key verification failed.)

Who knows what is going wrong?

Why are you using differnt users to connect to the remote host? root/pi?

Guess the general problem might be that the command is executed as root and you never have accepted the host key as root.

Option 1: Accept host key as root so that it is available when the command is executed

#become root
sudo su
#ssh into the remote host once
ssh pi@192.168.1.201
#store the key when asked

#pimatic rule
execute "ssh pi@192.168.1.201 'sudo reboot'"

Option 2: Disable host key verification for this ssh session

#pimatic rule
execute "ssh -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no pi@192.168.1.201 'sudo reboot'"

however this will only work if there is no password set for the user pi, otherwise one would need to use something like sshpass.

However I would not recommend doing it like this. There should be pimatic running also on the second pi and then you could use curl to trigger a rule which executes the reboot locally

Indeed, you have to accept the host key as root user, and use the root public key on the remote machine authorized_keys.

Installing pimatic on the remote machine is in my opinion overkill.

I also use the ssh method to shut down my NAS, and that works like a charm

{
  "id": "diskstation210",
  "name": "Diskstation 210",
  "class": "ShellSwitch",
  "onCommand": "/usr/bin/wakeonlan **:**:**:**:**:** 2> /dev/null",
  "offCommand": "/usr/bin/ssh *.*.*.* \"/sbin/shutdown now -h\"",
  "getStateCommand": "/bin/nc -z *.*.*.* 548 > /dev/null; if [ \"$?\" = \"0\" ]; then echo on; else echo off; fi",
  "interval": 1000
},

@thex and @rrooggiieerr I Did not had ssh root rights on the host that’s why i was using the pi user. With the root user it’s working. Thank You!