Siemens SCALANCE X-300 Configuration Manual page 353

The drop-down list shows the selection of possible ports for each device type. If the ports are
specified in the factory, the boxes are grayed out.
NOTICE
Ring ports after resetting to factory settings
If you reset to the factory settings, the ring port settings are also reset.
• CPs adopt the "Manager (Auto)" MRP role.
• With switches, the redundancy method Automatic Redundancy Detection (ARD) is
If other ports were used previously as ring ports before resetting, with the appropriate
attachment, a previously correctly configured device can cause circulating frames and
therefore the failure of the data traffic.
Diagnostic interrupts
Enable the "Diagnostic interrupts" option, if you want diagnostic interrupts relating to the
MRP status on the local CPU to be output.
The following diagnostic interrupts can be generated:
● Wiring or port error
Diagnostic interrupts are generated if the following errors occur at the ring ports:
– Connection abort on a ring port
– A neighbor of the ring port does not support MRP.
– A ring port is connected to a non-ring port.
– A ring port is connected to the ring port of another MRP domain.
● Interruption / return (redundancy manager only)
If the ring is interrupted and when the original configuration returns, diagnostic interrupts
are generated.
The occurrence of both interrupts within 0.2 seconds indicates an interruption in the ring.
Parameter assignment of the redundancy is not set by STEP 7 (redundancy alternatives)
This option only affects switches. Select this option if you want to set the properties for
media redundancy using alternative mechanism or tools such as Web based Management
(WBM), CLI or SNMP.
If you enable this option, existing redundancy settings from WBM, CLI or SNMP, are retained
and are not overwritten. The parameters in the "MRP configuration" box are then reset and
grayed out. The entries then have no meaning.
SCALANCE X-300 / X-400
Configuration Manual, 10/2014, C79000-G8976-C187-22
activated.
PROFINET IO functionality
6.5 MRP configuration
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