Set up networking between VMs on XenServer 7.4 and an Ubuntu 14.0 server on an internal network?

Question

Network administration

The server on the XenServer from it goes a cord to the external network through which
IP 37 is supplied. 192.XXX.YYY Subnet 178.49.XXX.YYY /
29 192.168.1.255 scope global xenbr1 Routing 0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 xenbr1 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 xenbr1 XEN has a virtual router. GATE inet 127.0.0.1/8 scope host lo inet 192.168.1.1/24 brd 192.168.1.255 scope global eth1 (Internal network) inet 37.192.XXX.YYY/24 brd 37.192.XXX.YYY scope global eth2

inet 178.49.XXX.YYY/29 brd 178.49.XXX.YYY scope global eth3
Routing
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 37.192.126.1 0.0.0.0 UG 0 0 0 eth2
37.192.126.0 0.0.0.0 U 255.205. 0 0 0 eth2
178.49.XXX.YYY 0.0.0.0 255.255.255.248 U 0 0 0 eth3
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1

Installed external hardware AS
inet 127.0.0.1/87 scope.lo host
inet XXX.YYY/29 brd 178.49.XXX.YYY scope global eth0
inet 192.168.1.9/24 brd 192.168.1.255 scope global eth1
Routing
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 178.49.XXX.YYY 0.0.0.0 UG 0 0 0 eth0
178.49.XXX.YYY 0.0.0.0 255.255.255.248 U 0 0 0 eth0
192.168.1.0 0.0.0.25.255 0 0 0 eth1

So all virtual machines see their addresses in the subnet 178.49.XXX.YYY/29
And the external hardware AS
Does not see the subgrid 178.49.XXX.YYY/29 and 37.192.XXX.YYY/32
But it is easily routed to the external network through the router Gate 192.168.1.1
All virtual machines and machines on the local network see 192.168.1.0/24, 178.49.XXX.YYY/29 and 37.192.XXX.YYY/32



In general, help.
I understand that the topic is specific. But in general, everything rests on the connection between the intermediate virtual network in xenserver and the physical network. Give directions. Then I will do everything myself.
The solution is to forward the traffic of the address 178.1.1.0/xxx with gate to the internal grid works. But it's kind of gross. I want to know what other methods are.