@Ebarlev 

There are two options for using VR600 in your case:

1. You could try to set VR600 as an AP (using one of its LAN ports for uplink to HALNY) thus avoiding double NAT in your LAN - check this thread for details on how to configure.

2. Set VR600 in 'Wireless router mode' (using its LAN4/WAN port for uplink to HALNY) with its DHCP server enabled, introducing double NAT in your LAN - details.

You have to determine which of these two options will suit your needs best.

Ebarlev wrote

  @terziyski 

Thank you for your quick response , 

Final result : VR600 as an AP doesn't work , perhaps the following details shall reveal more information which might be of Aid to the issue:

Description:

• HALNY Fiber-router is connected directly to a fiber
  • The router has a max-2.4GHZ client limit of 31 clients , I am over the top
  • the router's base address ( Also the Gateway ) is 10.0.0.138 netmask 255.255.255.0 
  • Internet Works great
  • I read some os the side notes, and denoted the DMZ interface to be at 10.0.2.140 ( Explanation soon )
  • I consulted the support company and indeed it sends traffic through the Ethernet interface to this address
• VR600 Router
  • Configured base address to 10.0.0.140
  • DHCP Enabled ( I would like it to allocate addresses , else appealing to the HALNY for it will kill the last address after the 32nd client , will it not ?)
  • DHCP Range : 10.0.0.141-200 , netmask 255.255.255.0 , GW= 10.0.0.140.

 

I first left the VR600 as a DSL MODEM , connected the input to LAN1 , didn't work . Internet connection at the app showed a red X , saying nothing works

Changed the VR600 to a "Wireless router mode" and left the input on LAN1 , still, nothing worked. reconfigured the interface of the EWAN ( LAN4) to take static IP of 10.0.2.140 and now there still is no Internet , however , the network connection is no longer a rex "X" , it is , instead, a yellow "!" , what does it say ?

 

Whenever I tried changing the DHCP to "Disabled" , as soon as the router rebooted it was no longer accessible through any means yet I indeed got addresses as if I was connected to the first router ( Meaning the DHCP of the first router works through the VR600 , however, it is totally unreachable and no internet connection as well ) 

 

Any insights which might shed some light here will again be appreciated

  @Ebarlev 

In either cases, if HALNY has 10.0.0.38 as its LAN IP address, you should not use (for VR600 WAN/LAN4 or LAN1) IP address like 10.0.0.2.140, but 10.0.0.140 instead - these are in different subnets and that matters.

If you want to have VR600 DHCP server enabled for your use-case then use VR600 in "Wireless router mode" and set DMZ on HALNY to 10.0.0.140.

The other approach would be to use VR600 in "AP mode" avoiding the double NAT, but you have to set static IP addresses on some of the IoT devices to overcome the HALNY's limitation of 32 clients (I wonder if it's because HALNY's LAN network mask, its DHCP reservation feature or a HW limitation ?).

If you choose to use VR600 in "AP mode" its DHCP server should be turned OFF - use the thread I posted as an example, just use an IP addresses according to your addressing scheme.