I think your Linux server have been configured for disallow ssh login via Password. It could be public key. I was able to reproduce your error, so I suspect this could be the cause.
PS C:\Users\Administrator> Invoke-NaSsh -Name 10.226.179.194 -Command "dfm about" -Credential $cred
Invoke-NaSsh : No suitable authentication method found to complete authentication.
At line:1 char:1
+ Invoke-NaSsh -Name 10.226.179.194 -Command "dfm about" -Credential $cred
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidResult: (:) [Invoke-NaSsh], SshAuthenticationException
+ FullyQualifiedErrorId : SshExecFailed,DataONTAP.PowerShell.SDK.Cmdlets.Toolkit.Ssh.InvokeNaSsh
PS C:\Users\Administrator>
Open file : /etc/ssh/sshd_config using vi editor and see what is the configuration set for authentication via passoword.
Look for these line:
PasswordAuthentication no
Modify it to yes and restart the ssh service.
# service sshd restart
Stopping sshd: [ OK ]
Starting sshd: [ OK ]
After this, test with Invoke-NaSSh and see if you are able to connect and run commands. I think this should fix it for you.
Let me know how this worked for you.
sinhaa
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