Is it possible to have multimaster configuration in Modbus TCP/IP
It is possible that Two masters are connected to same slave via MODBUS TCP/IP .
In case of failure of one master , second master can control and monitor this slave.
I'am not sure, which system you are talking about. If you ask it for 800xA System.
CI867 Modbus TCP Cards can act as redundant, so both card are connected to same slave. In case of a failure of master, communication cards switch over.
But please see attached picture below for more switching details.
Hope it helps you.
In addition to Titus answer, for any general case from the Protocol side yes you can connect any number of Masters for the same Slave at the same time. This is different to Modbus RTU.
It needs to be supported by the Client though, most slaves cannot do this but for example i know that the MNSiS MLink supports it.