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Device handbook SINEAX AMx000
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IPv4: Mode >> DHCP
If a DHCP server is available, alternatively the mode „
DHCP
“ or „
DHCP, addresses only
“ can be
selected for the Standard interface. The device then gets all necessary information from the DHCP server.
The difference between the two modes is that for “DHCP” also the DNS server address is obtained.
The settings obtained from the DHCP server can be retrieved locally via the service menu.
Depending on the settings of the DHCP server the provided IP address can change on each
reboot of the device. Thus it’s recommended to use the DHCP mode during commissioning
only.
Time synchronization via NTP protocol
For the
time synchronization
of devices via Ethernet
NTP
(Network Time Protocol) is the standard.
Corresponding time servers are used in computer networks, but are also available for free via Internet.
Using NTP it's possible to hold all devices on a common time base.
Two different NTP servers may be defined. If the first server is not available the second server is used for
trying to synchronize the time.
If a public NTP server is used, e.g. “pool.ntp.org”, a name resolution is required. This normally happens
via a
DNS server
. So, the IP address of the DNS server must be set in the communication settings of the
Ethernet interface to make a communication with the NTP server, and thus time synchronization, possible.
Your network administrator can provide you the necessary information.
The time synchronization of the Standard interface can be performed via a
TCP ports
The TCP communication is done via so-called ports. The number of the used port allows determining the
type of communication. As a standard Modbus/TCP communication is performed via TCP port 502, NTP
uses port 123. However, the port for the Modbus/TCP communication may be modified. You may provide
a unique port to each of the devices, e.g. 503, 504, 505 etc., for an easier analysis of the communication
traffic. Independent of these setting a communication via port 502 is always supported. The device allows
at least 5 connections to different clients at the same time.
Firewall
Due to security reasons nowadays each network is protected by means of a firewall. When configuring the
firewall you have to decide which communication is desired and which have to be blocked. The TCP port
502 for the Modbus/TCP communication normally is considered to be unsafe and is often disabled. This
may lead to a situation where no communication between networks (e.g. via Internet) is possible.