how to assign an address from a local network for management

[eem-kz]

Faced with such a problem:
There is a head office and branches. A gateway (R81.10) is installed in one branch, which has a channel (closed) connected to one interface, a second LAN (10.61.127.1).
The interface to which the channel is connected is assigned a P2P address (172.16.25.17), which is not routed in the provider's network.

There is no access to the P2P address from SMS (R81.20), but there is an address on the Lan. But, the gateway itself, when it accesses SMS, there is no access, because the P2P address is substituted.

Question: how to assign an address from a local network for management, since there is a restriction "you cannot assign two IP addresses from the same subnet"? For example, Cisco has Vlan interfaces, is there such (any) solution to this problem?

I'm sorry that I use a machine translator

[G_W_Albrecht]

Provide a topology sketch - i do not understand the configuration!

[the_rock]

Its not a big deal you use language translator, thats fine, but I think simple network diagram would help us understand this better.

Andy

[G_W_Albrecht]

I would heavily suggest to learn english when working in IT 😎 Makes things really much easier, i had to do that, too...

[the_rock]

You are right, but its not easy for everyone. We are here to help, regardless if someone uses translator or not...no judgments.

Andy

[G_W_Albrecht]

Of course, why do you write that ? It was just an addition to your reply, no judgement intended at all. Fact is that you will be much better off that way, and it is rather easy to learn compared to e.g. finnish 😉

[the_rock]

You can ty learning Serbian language HAHAHA...it will take you 50 years to master 🤣🤣🤣🤣

[G_W_Albrecht]

I did that a bit and now know all the bad words as most sentences start or end with them 😎

[the_rock]

Yea, pretty much 😂😂😂

[PhoneBoy]

A simple network diagram would be very helpful.

[eem-kz]

Friends, here is the connection diagram

[the_rock]

Im sorry, but Im still totally unclear as to what exactly the goal here is. Are you trying to assign an IP to SMS (R81.20) mgmt server from 10.61.127.0/25 subnet? 

Andy