SSH Shell error after RDM update

Hello,

Thank you for contacting support departments, in the meantime we are doing the diagnostic could you test this workaround: enable *Legacy Terminal* under *File > Options > Types > Terminal > Advanced* .

For the issue could you please send us your logs?
https://devolutions.atlassian.net/servicedesk/customer/portal/1/topic/dddd3564-78f7-4943-941e-45d9117806be/article/608731251

Best regards,

I'm sorry but no luck.
I get the same response again

Hello,

Thanks for the test, if the legacy mode does not work this mean the issue is not related to our new SSH engine but something else.

Unfortunately we haven't received the logs, could you please tell me if you sent them by email at ticket@devolutions.net or somewhere else?

Regards,

Hi, We got the same error in the update 2020.3.23.0 64bit
When using your advice to change to legacy it works.

The following error does occur:

Hello Kaj,

Thank you for reaching out to Devolutions Support.

The error you have encountered is a slightly different one, first introduced following a change we did in RDM RDM 2020.3.12.0. Starting with this version, SSH Shell no longer enabled unsecured algorithms by default.

The simple way to resolve this is to go into your entry's Properties, go to the Advanced tab and find the "Algorithm support" field. You will need to set it to "Custom" then press the "..." button and check all algorithms in all sections. (Cipher, Host key, Kex, and MAC)

For more information on the subject, as well as the procedure to apply this solution globally instead of on specific entries, I invite you to consult our knowledge base article on the topic :
https://kb.devolutions.net/rdm_ssh_algorithm_support.html

Best regards,

So we need to change all the SSH entries?

Okay that works, but it is not something we want! Is there an option to force this for everyone?

Hello,

As mentioned in the help topic, it's also possible to globally reactivate all the algorithms by using the File - Options - Types - Terminal - Algorithm support menu.

Best regards,

Hello,

I saw that but we have more then one user.. We want to enable this through datasource our something.

Hello Kaj,

You can modify multiple SSH entry at the same time, you simply need to select all the SSH entries in RDM, do a right-click, Edit, Edit (special Actions)

Select Custom PowerShell Command:

Enter the following script and press ok:

$Connection.Terminal.AlgorithmSupportMode = "Custom" 
$Connection.Terminal.SshAlgorithmCipherList = "aes256-gcm@openssh.com=True;aes128-gcm@openssh.com=True;aes128-cbc=True;aes192-cbc=True;aes256-cbc=True;rijndael-cbc@lysator.liu.se=True;3des-cbc=True"
$Connection.Terminal.SshAlgorithmHostKeyList = "ssh-dss=True"
$Connection.Terminal.SshAlgorithmKexList = "diffie-hellman-group14-sha1=True;diffie-hellman-group-exchange-sha1=True;diffie-hellman-group1-sha1=True"
$Connection.Terminal.SshAlgorithmMaclist = "hmac-sha1-96=True;hmac-sha1=True;hmac-md5-96=True;hmac-md5=True"
$RDM.Save();

You should then be able to connect normally to your SSH connections.

Best regards,

What can we do to fix this so RDM can connect to an SSH session(switch)?

Thank you we will do this

Hello Kaj,

You can modify multiple SSH entry at the same time, you simply need to select all the SSH entries in RDM, do a right-click, Edit, Edit (special Actions)

Select Custom PowerShell Command:

Enter the following script and press ok:

$Connection.Terminal.AlgorithmSupportMode = "Custom" 
$Connection.Terminal.SshAlgorithmCipherList = "aes256-gcm@openssh.com=True;aes128-gcm@openssh.com=True;aes128-cbc=True;aes192-cbc=True;aes256-cbc=True;rijndael-cbc@lysator.liu.se=True;3des-cbc=True"
$Connection.Terminal.SshAlgorithmHostKeyList = "ssh-dss=True"
$Connection.Terminal.SshAlgorithmKexList = "diffie-hellman-group14-sha1=True;diffie-hellman-group-exchange-sha1=True;diffie-hellman-group1-sha1=True"
$Connection.Terminal.SshAlgorithmMaclist = "hmac-sha1-96=True;hmac-sha1=True;hmac-md5-96=True;hmac-md5=True"
$RDM.Save();

You should then be able to connect normally to your SSH connections.

Best regards,

Hello Kaj,

My pleasure, let us know if you encounter any issue after running the script.

Best regards,

Hello Kaj,

My pleasure, let us know if you encounter any issue after running the script.

Best regards,

Do you know how we can fix the switches, so RDM does not need to be modified?

Hello Jan,

The change was made for security reasons, independent of the remote device you are connecting to.

If it is impossible to change the algorithm used for the ssh session you are connecting to, we recommend creating a template, and create new entries from it. For more information on templates, you can refer to our online help:
https://help.remotedesktopmanager.com/commands_creatingtemplates.html

Best regards,