Hi Ovez,
Steps in a nutshell are:
Deploy VM with one nic connected to the network
Configure IP address and GW (WAN Router)
Configure Traffic Policies to match local subnets (Source) to remote subnets (Destination)
Add default #99 bypass to pass-through all other subnets traffic
(v.2.x to v.3.x) Configure Multisite subnets that match traffic policies with remote peer IP address (start with site-0)
(or v.4.x) Configure Tunnel Policies that match remote subnets with remote peer ip
Switch to UDP encapsulation
Switch to Tunnel deployment
Configure Server-A in Site-A to use Wanos-A as default gateway
Configure Server-B in Site-B to use Wanos-B as default gateway
Test non-bypassed TCP traffic between Server-A and Server-B (e.g. HTTP, FTP)
One side "Up/Active" while the other side is "Idle" usually indicates asymmetric/one way traffic flow.
Since Wanos-2 shows up, it means Wanos-1 is probably configured OK.
Look to see that the Servers at Site-2 has Wanos-2 as default GW.
Once the setup is functional between Server-1 and Server-2 with default gateways, then next look at configuring more interesting routing setups with Policy based routing etc.
Note a difference between v.3 and v.4 tunnel mode:
v.2-v.3 Only optimized traffic is tunneled while the peers are online e.g. excluding ICMP
v.4 All traffic is tunneled, including ICMP