RV 340 web console access goes down

[sumesh]

We have a RV340 dual WAN router. The device works with the following setup.

WAN1 : Has ISP connected,  w.w.w.w/28 subnet

LAN1 : Has one LAN connected , vlan1 enabled, x.x.x.x/24 subnet

LAN4: Has configured with LAN4 as DMZ and hosts a number of internet facing servers, vlan4 enabled with the w.w.w.w/28 subnet. Servers are connected to an unmanaged switch which is connected to LAN4 of router. 

LAN2 and LAN 3 ports are not used now.

Admin console access with web interface enabled from LAN ip as well as WAN ip. This works fine. 

But now I need to add another LAN ( vlan2)  which serves as a 'Guest only network'. to serve internet access to guests. I enabled VLAN in the internal network switches with vlan2, ip address y.y.y.y/24 range. I found inter VLAN traffic is functioning and guest are able to access internet. However it has been learned that the moment I enable vlan2 interface on router I lose access to the router admin console using web interface, but still to and fro traffic on all LANs and WAN are functional. Since I lose the console access I am unable to save the configuration, so with a simple power recycle I am unable to restore the console access, but now the vlan2 configuration gets vanished as it was not saved before power recycling.

I am unable to understand the root cause , is it a technical glitch in RV340 or something wrong with my configuration !  Please assist. 

[Kasun Bandara]

if you reboot device without saving, all unsaved configuration will clear. so after reload you will not see unsaved changes and you will have last saved configuration.

[sumesh]

Hi KB,

   Thanks for your response. I understand the unsaved configuration changes will not persist after reboot. Here I am wondering about the root cause which makes the web console inaccessible while adding vlan2, at the same time all other traffic works as fine as expected. 

[Inland-OZ]

Hey, I have experienced that in a different way and I don't reckon it will solve this for you, but:

https://community.cisco.com/t5/small-business-routers/rv340-web-interface-gui-goes-offline/td-p/4434691

What I found helps these routers' (RV34x) is:

• Save the running configuration XML file to a management PC
• Hard reset (press fp button for over ten seconds)
• Login and upload the configuration XML
• TAC advised this for me on another fault, has been a solution at times

[balaji.bandi]

if i recall, in the community some user have raised same issue, not able to get the thread, yes looks like some issue as per the user.

contact SMB TAC to investigate for you, this not a standard behaviour as per i know.