2 Siemens Comfort HMI's Master Slave

I'm putting together a system with a Redundant S7-1500 CPU and 2 Comfort HMI’s on an MRP ring.
The HMI’s will be doing the same job and only one person should be on the site operating them.
Is it possible to set them up as a master and slave?
The things I would like to achieve:
1.Logging into one HMI would automatically log the other one off
2.If a user is created at runtime on one HMI, it would also be available on the second HMI
3.The event logs/audit trail would match, but in the event of a failure of one HMI the 2nd one can still display the log

1. Is there any particular reason why both can't be masters all time?
I assume that connection is profinet as you are connecting them to MRP ring.

The easiest way to do most of the required features would be to set it up where one HMI displays the other with Sm@rtserver/Sm@rtclient. Only one can be operated at a time, and the logs would all be in one place. However, that wouldn't give you failover capability. It simply allows HMI 2 to more or less be a remote display for HMI 1. The logs/users/etc only exist on HMI 1.

The HMIs are single station HMIs, not a client/server SCADA setup or a redundant system. Changes rolled out to 1 do not get automatically deployed to 2, and users/logs/etc, do not automatically get shared.

1) would be possible via scripting, I think. I've seen systems do things to control which HMI is in control of a machine/system/etc. You can log off via system function or script, and you can control whether objects are enabled via animation.

2) I think there is a system function you can use to export the user admin from the HMI. With luck, maybe you could do it to a shared network drive, then import from the other side? You could also use SIMATIC Logon to centralize the user administration to some PC somewhere, or active directory.

3) I think the audit logs can be exported to a network drive as well. They wouldn't MATCH, but you could export both of them, to protect against an HMI going down.

Lare said:

1. Is there any particular reason why both can't be masters all time?
I assume that connection is profinet as you are connecting them to MRP ring.

Click to expand...

No reason, as long as both are not logged in together, as mk42 says, that could be done with script,
For the adding a user, the worst case would be they have to add one on both HMI's,
I could really do with a common Audit trail though