Lost VNC connection for Siemens HMI & **** 4G modem

[woolie161]

Hi Experts,
One of our clients, until recently, could connect remotely via the internet to a Siemens TP1200 Comfort HMI via VNC and **** Cosy 131 using "******".

After entering the credentials for access, the page changes to Error 404. /M2WebGuacamole/Home

I can still log into the **** via eCatcher and I can access all the devices on the LAN.

I have the local "guy", cycle power to the HMI, I have also re-booted the ****.
I desperation, I have done a download to the HMI with the original file (that used to work until a couple of days ago). I have even updated Google Chrome and then the firmware of the ****.

Has anybody had the same experience or have some suggestions of my next course of action?

Thank you
Woolie

 

[JesperMP]

It seems you are using either a 3rd party VNC viewer, or a webbrowser for accessing the panel.
I suggest using the Siemens smartclient.
Can someone onsite access the TP1200 via the smartclient ?

 

[woolie161]

Thanks for the quick reply Jesper,
Siemens SmartClient has been selected in the HMI Runtime settings. Unfortunately, this plant is remote and usually un-attended. The HMI could be accessed via "m2web.******.com" and logging in from that page. It has now stopped working.
Is Siemens SmartClient software that can be downloaded from the Siemens site?
Woolie

 

[woolie161]

Hi Jesper,
I have just downloaded Siemens Smartclient and I can now connect to the HMI. Although not as convenient as the previous method. This one works! I'm not sure what happened to the other method to stop it working.

Thank you. I appreciate you help

Woolie

 

[JesperMP]

It has been known that Siemens Smartserver works with 3rd party VNC clients.
But it is also known that some firmware updates breaks this.
Siemens is adding a lot of security features to all PLCs and HMIs, so it will be even less likely that 3rd party solutions will work in the future.

 

[woolie161]

Again, thanks for sharing your knowledge.
woolie

 

[mk42]

It has been known that Siemens Smartserver works with 3rd party VNC clients.
But it is also known that some firmware updates breaks this.
Siemens is adding a lot of security features to all PLCs and HMIs, so it will be even less likely that 3rd party solutions will work in the future.

In general, agree.


In the specifics of this, though, my understanding is that the Siemens VNC implementation actually lacks some very common security features that actually make it tricky to connect with many 3rd party VNC clients.


Doubt there will be many/any more updates to the Comfort panels at this point tho. I don't think they got any updates in Portal V18; Siemens seems all in on the Unified stuff.

 

[woolie161]

Hey mk42,
Thanks for checking in and adding your thoughts. I eventually found a solution to the issue. Using the M2M setup to access the Siemens HMI remotely, when selecting the device to connect to (via M2M website) the system would add "/Home" to the VNC: #### number. If I manually delete "/Home", I can access the HMI.
Again thanks for your comment.
Woolie