Siemens SINUMERIK 840D sl TCU 30.3, Manual

Page: 36 / 88

5.1.3 System boot with system network
System behavior at boot
The system boot behavior is based on the following principle:
● For configuration of an NCU 7x0 with a PU 50, the default for a network configuration is as
follows: The NCU keeps the default IP address 192.168.214.1 on X120, the PCU 50 keeps
the default IP address 192.168.214.241 on Eth2.
● For a configuration of more than 1 NCU 7x0 without PCU, with one or several PCU 50, then
a differentiation must be made between two cases:
– At boot automatically all address conflicts and DHCP conflicts are resolved and the
system is ready for operation. In this configuration, there is no guarantee that, on every
system boot, all NCUs and PCUs will always be given the same IP address.
– If the user requires all NCUs, and possibly also the PCUs, to have a defined constant
IP address at each boot, for example, because the IP address is stated explicitly in the
PLC program, the user must configure a fixed IP address for each NCU 7x0/PCU 50 in
question, in the basesys.ini file.
● The user can specify a DHCP master in the basesys.ini file.
● Assigning names:
– The user should assign meaningful names for all NCUs in the basesys.ini file; if not the
names will be generated automatically.
– A PCU 50 always has a computer name that can be changed as needed.
● IP addresses of the TCU und MCP are freely assigned from a prescribed address range
on every system boot. The MCPs are identified in the PLC by their DIP switch setting.
Using DNS name service
Availability of the DNS (Domain Name System) name service offers the following advantages
for system network administration:
● The name service enables easier configuration with names instead of IP addresses for
management of operating units: All components in the system network can be addressed
via a symbolic computer name. This name can to some extent be freely assigned, to some
extent it is derived automatically from a DIP switch setting (MCP, MPP, EKS, HT 8, HT 2).
● A computer node in the system network (NCU, PCU, TCU, MCP, HT 8, etc.) can be
addressed solely through assignment of the IP address, either via a freely selectable name
or via an internally generated name in the system network, and thus becomes independent
from its network address in the system network. Thus a change in the network address
does not necessarily necessitate a series of additional setting changes.
● In addition, the name service is used by the system for address resolution for MCP/MPP,
direct keys, and EKS when changing the user authorization.
Networking
5.1 System settings
TCU 30.3
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Manual, 09/2017, A5E40874197