Ethernet network configuration from web page

[Authorless]

I'm using a system SlimLine based on Cortex M7, I have a doubt about the web page configuration.

Given that I have enabled the DHCP client and therefore, when turned on, the system acquires the configuration from the corporate DHCP server. Now if I view the configuration page from a browser I see the configuration provided by the DHCP server, but if I act with the mouse on the gear for the set of values ​​I see other values ​​in the display, I don't understand ...

[Sergio Bertana]

Activating the DHCP client it SlimLine when it is turned on, it looks for the DHCP server and if it finds it, it requests the configuration parameters. Parameters which are used to configure the network interface and which are displayed in the relevant window (Screenshot) (In the example we have IP: 192.168.1.77, MASK: 255.255.254.0, GATEWAY: 192.168.0.1, ...).

But if the DHCP server is not found, the system is configured with the parameters set through the configuration pop-up (In the example we have IP: 192.168.0.125, MASK: 255.255.254.0, GATEWAY: 192.168.0.1,…).

The configuration parameters (those that can be set in the pop-up) can also be managed by the user program via the function SysOSIDValue, using the IDs:

OSID_ETH0_DHCP_DNS BOOL (ETH0) Enable DNS acquisition from DHCP
OSID_ETH0_DHCP_EN BOOL (ETH0) Enable IP acquisition from DHCP
OSID_ETH0_DNS_PRIMARY USINT[4] (ETH0) Primary DNS IP address
OSID_ETH0_DNS_SECONDARY USINT[4] (ETH0) Secondary DNS IP address
OSID_ETH0_GATEWAY USINT[4](ETH0) Gateway IP address
OSID_ETH0_IP USINT[4] (ETH0) IP address

At present, no OSIDs are defined for reading the current configuration active on the ethernet interface.

Note: If you want the parameters set with the function SysOSIDValue remain saved in the system configuration needing to execute the function with OSID_CFG_WRITE.

[Rubox]

I am confronted with the following problem. I have to develop a program for a client, on an isolated LAN, on which there is no router. Under gateway settings of the SlimLine what should i put in it?

Until now I had developed systems connected to the internet and the gateway was the router to the outside, now I don't find any router. Now the same programs that work with a router present no longer work: for example EMailSend. How do you behave in this case?

Does the PLC always need a gateway, and therefore a router on an isolated LAN network?

[Rubox]

Rewind: any IP gateway on a LAN is fine. The email did not send me because I forgot that in the JSON encoding it is not possible to insert the colon character.

The email is now sent and received by the local email server.

[Sergio Bertana]

The IP address of the gateway in the network configuration of any device must be that of the device that allows it to communicate with the Internet, or in any case with other networks outside the network class configured for the product.

So assuming that the IP of the SlimLine is the default 192.168.0.122/24 when trying to communicate with an IP outside the network class, the packets are sent to the IP address of the gateway that will route them to the network to which the IP address belongs.

If there is no need to communicate with devices outside your network class, the gateway is not necessary and the field can have any value.

[Author]

Post