Is there any way to connect from Mikrotik router as vpn client to Nethserver?

NethServer Version: 7.4
Module: your_module

Does the router support acting as an IPsec or OpenVPN client?

yes, as openvpn client but not support udp

Is it possible to change udp to tcp? Or how can i get back l2tp/ipsec under v7? On V6 that was the only solution to use mikrotik with nethserver…

IPsec is still supported in v7.
http://docs.nethserver.org/en/v7/vpn.html#ipsec

Yes, without l2tp…

You could create this file: /etc/e-smith/templates-custom/etc/openvpn/host-to-net.conf/15tcp containing:

proto tcp

Unfortunately, I’m not sure which event needs to be run following this to re-build the host-to-net.conf file. I’m sure someone else will chime in on this. Or, in the meantime, you could just add that line to /etc/openvpn/host-to-net.conf and re-start the service. The above file will protect you against future updates re-building the file.

** Edit ** You will also have to open the firewall, as by default port 1194 is only opened to UDP.

Cheers.

I have OpenVPN configured Authentication Mode: Certificate. I want to set up a connection via Mikrotik. Which certificates do I need to copy to Mikrotik? xx.ovpn, xx.pem, xx.p12?

You only need the ovpn file. The required certificates are embedded.

Cheers.