Siemens SCALANCE XM-400 Configuration Manual page 289

● Force device to Standby Master
If you select this check box, the device is configured as a standby master regardless of its
MAC address.
– If this check box is not selected for either of the devices for which the standby master
– If the option is selected for both devices or if the "Force device to Standby Master"
This type of assignment is important in particular when a device is replaced. Depending on
the MAC addresses, the previous device with the slave function can take over the role of
the standby master.
Note
If the option "Force device to Standby Master" is enabled on both devices of a standby
coupling, this can lead to circulating frames and therefore to failure of the data traffic. Enable
the "Force device to Standby Master" option only on one device of a standby coupling.
● Wait for Standby Partner
– Enabled
– Disabled
SCALANCE XM-400/XR-500 Web Based Management (WBM)
Configuration Manual, 05/2017, C79000-G8976-C248-12
is enabled, then assuming that no error has occurred, the device with the higher MAC
address adopts the role of standby master.
property is supported by only one device, the standby master is also selected based on
the MAC address.
A standby connection is enabled only after the standby master and the standby slave
as well as their standby partners have established a connection. This ensures that the
redundant connection is really available before communication via a standby connection
is enabled.
A standby connection is enabled even if the standby master has not yet established a
connection to the standby slave.
This can lead to circulating frames and failure of the data traffic if another standby
connection has already been enabled. Multiple standby connections can, for example,
result due to configuration errors if different standby connection names were assigned
to the standby master and standby slave.
Configuring with Web Based Management
5.5 The "Layer 2" menu
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