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sFTP and Datto Port 2222



We have a phone system (Switchvox) that sends backups to a Datto Siris DR appliance via sFTP. This was recently changed from FTP. We were able to monitor it via FTP without problem, but since switching to sFTP we can't get it to work with PRTG.

Datto runs sFTP on port 2222.

With default SSH Engine I get this:

Failed to connect. Please check the SSH log of the target device or try the Compatibility Mode of the sensor's SSH engine and consider updating the target system's operating system. Reason: ssh_connect failed (-1)kex error : no match for method mac algo client->server: server [[email protected],hmac-ripemd160,hmac-sha1-96,hmac-md5-96], client [hmac-sha1,none]

In compatibility mode, I get this error:

The negotiation of mac algorithm is failed

In both cases the Result of Sensor file seems to report the same as above, but I can post those files if they have any other useful information.

I have reached out to Datto, but I don't know if they are going to help me beyond saying it's working for one system. I don't have any back end/ssh access to this system to see much in the way of data.

Is there any way to get this to work with PRTG?

Connection timeout is 60 Sec. Shell timeout is 10 sec. SSH Port is custom 2222. Linux credentials are specified for the device, login via password, for wbem use https, wbem port auto. I just tried changing the SSH port from 22 to 2222. I haven't played with the SSH rights elevation or engine options, do they impact the sFTP sensor?

datto sftp siris ssh-connect-failed

Created on Oct 25, 2018 7:11:26 PM

Last change on Oct 26, 2018 10:30:44 AM by  Sven Roggenhofer [Paessler Technical Support]

2 Replies

Accepted Answer



Hello schester,

While our sensor supports the encryption methods hmac-sha1 your server supports [email protected],hmac-ripemd160,hmac-sha1-96,hmac-md5-96 "only".

I've found a similar case where the problem was related to a bug on the server. So, please contact Datto support and ask if they can change/fix this to support hmac-sha1 as well.

Best regards,
Sven Roggenhofer [Paessler Technical Support]

Created on Oct 26, 2018 11:36:35 AM by  Sven Roggenhofer [Paessler Technical Support]



Thanks Sven. I've reached out to Datto to see if they can make this change for us!

Created on Oct 26, 2018 11:42:59 PM

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.