Error: Error executing command on leaf02. Error Code: 255

I had a issue today with running remote commands on one of my fabric switches, always generated an error.

apic1# fabric leaf02 show switchname
----------------------------------------------------------------
 Node 102 (leaf02)
----------------------------------------------------------------
Error: Error executing command on leaf02. Error Code: 255

I tried to directly connect and found the error

admin@apic1:attach leaf02
This command is being deprecated on APIC controller, please use NXOS-style equivalent command
# Executing command: ssh leaf02 -b 10.127.240.1
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that the RSA host key has just been changed.
The fingerprint for the RSA key sent by the remote host is
d1:f1:c4:8a:3e:a7:df:4a:76:bf:ec:01:bb:0d:28:99.
Please contact your system administrator.
Add correct host key in /home/admin/.ssh/known_hosts to get rid of this message.
Offending key in /home/admin/.ssh/known_hosts:2
Password authentication is disabled to avoid man-in-the-middle attacks.
Keyboard-interactive authentication is disabled to avoid man-in-the-middle attacks.

Permission denied (publickey,password,keyboard-interactive).

I think this was the switch that i converted to NX-OS standalone mode, and thus it changed the host key.

The fix is easy, open the file and delete the offending key

vi /home/admin/.ssh/known_hosts

After that i was able to run commands from the apic and also connect to the fabric switch again.

Cisco ACI – Connect to the leaf/spine switches with the NX-OS

Some time ago i posted how you can connect to a spine or leaf switch -> Connect to a leaf/spine switch
With the introduction of NX-OS, the syntax changed a bit. You have now first to drop back to the bash shell and then you can attach the switches. Password is still the same as for the APIC.

apic1# bash
admin@apic1:~> attach leaf01
This command is being deprecated on APIC controller, please use NXOS-style equivalent command
# Executing command: ssh leaf01 -b 10.127.240.1

Password:
Cisco Nexus Operating System (NX-OS) Software
TAC support: http://www.cisco.com/tac
Copyright (c) 2002-2016, Cisco Systems, Inc. All rights reserved.
The copyrights to certain works contained in this software are
owned by other third parties and used and distributed under
license. Certain components of this software are licensed under
the GNU General Public License (GPL) version 2.0 or the GNU
Lesser General Public License (LGPL) Version 2.1. A copy of each
such license is available at
http://www.opensource.org/licenses/gpl-2.0.php and
http://www.opensource.org/licenses/lgpl-2.1.php
leaf01#

There is also the possibility to directly run show commands from the APIC.
Run Commands on the Fabric Switches from your APIC