Hello all,
I have a problem assigning a static IP to the ether1 where the DSL-Router is connected.
It works while I use a DHCP-Client for ether1 and the default route and the route from ether1 interface
are created. Setting the interface ether1 to a static IP instead of using DHCP-Client, adding the routes
manually (default route and route to the ether1 network) doesn't work, unfortunately.
What was my fault here? Thanks for help Best regards, Mike.

Sounds like you have configured the mikrotik correctly but the modem has been left unconfigured. Possibly an arp issue. Add the mac and ip to the arp table on the modem and see if that helps.

EDIT: Why not have the dhcp-server on the modem assign a static IP to the device and just have it set as dhcp client on the tik? That way if there is not an IP assigned and the tik is searching there is an issue with the modem.

Hi NicholasMag,
I'm afraid, there is no possibility to modify the ARP-table of the modem, and no possibility to configure the modem to assign a static ip to the device. Is there any other solution? Best regards, Mike.

I dont believe this is possible if you cannot change anything on the modem. Maybe throw in a small tik device between the modem and your device just so u can get the static IP?

Could you possibly put the modem into a bridged mode and have the tik handle the wan?

I suggest that you port output from /export compact.

If you have the IP and subnet set correctly on that interface then the static route to that network should appear in the routing table with an S designation. If that isn't happening then something is wrong with the static IP assignment.

Hi,
yes, the static route was created as you mentioned. But the final result is, that no connection to the internet is possible. Unfortunately Best regards, Mike.

DHCP is probably setting:

IP number, subnet, gateway

Route to link network

Default route

DNS servers

so the answer is most likely on one of those.

Post /export compact output for comment if you can't find the problem.

If you can ping 8.8.8.8

My guess would be in
IP
DNS
Allow Remote requests

Thank you for your help. Ultimately, I decided for the following solution:
The DSL router as a DHCP server with an address range from only 1 IP address. So I can predict what IP address is assigned to RB750 interface. Thus, this problem is solved.