whould you explain me how can i do this?
I have one mikrotik level 6 with 2 lan interface.
one of them connected to a valid subnet. and the other is connected to the invalid subnet. my external subnet is 217.219.100.128/25 i want to route 217.219.100.224/27 to my internal network.
please explain me what ip should i set in my invalid interface and how can i route this.

Unfortunately it's not clear what you're trying to do.

Do you have an existing internal IP address range? If yes, what is it?

If you have less than 29 devices on you internal network you could just bridge it, allocating addresses from the 217.219.100.224/27 range to internal devices.

If you have more than 29 devices you will need to use a private IP address range or sub-divided range, e.g. 10.0.0.0/8, 172.16.0.0/12 or 192.168.0.0/16, for your internal network and use NAT rules in the Firewall to redirect external public addresses to internal private addresses.

imagine that you have a cisco router. and you want route one subnet to one of your interfaces.
you have for example 217.219.100.128/128 in your serial interface. then you set 217.219.100.129 to your fast ethernet and ip unnumbered fastethernet 0 to your serial interface. then you want to route 217.219.100.224/27 to fast ethernet 1 interface. then you must write ip route 217.219.100.224 255.255.255.224 fastethernet 1.
i want to know how can i do this by mikrotik. just this.

The analogy with Cisco is somewhat lost on me, never got to grips with them, that's why I use MikroTik!

Anyway, I think it's clearer what you're trying to do. I haven't tried to route/bridge a subnet of one range to another interface, but I would think one of the two following methods should work.

In both methods:-

1. Allocate an IP address on the external interface e.g. 217.219.100.129/25
2. Allocate an IP address to the internal interface e.g. 217.219.100.225/27


Bridged method

3. Create a bridge.
4. Allocate the ethernet interfaces to the bridge.


Routed method (where x is IP address of the Internet Gateway)

3. Create a route for network 217.219.100.224/27 via gateway 217.219.100.225/27.
4. Create a route for network 0.0.0.0/0 via gateway 217.219.100.x/25.

To create a route from the CLI use:-

/ip route add dst-address=217.219.100.224/27 gateway=217.219.100.225/27
/ip route add dst-address=0.0.0.0/0 gateway=217.219.100.x/25

Regards

Chris Macneill

thank you so much.
I used cisco just for example.

Well cisco's default to having proxy-arp enabled.
Add the larger network to one ethernet and enable proxy-arp (arp = proxy-arp)
Add the smaller network to a second ethernet.
should be equivalent.

hello
I think there is mikrotik forume.
if you wana to work with mikrotik you should buy it first. and read its manual.
be success.