RV345P basic DMZ setup question

[sicher]

Hello,

I got my RV345P today but I can't get the DMZ setup for my mailserver to work (as it did with my Linksys LRT214).

Setup:

1) ISP modem with 80.x.y.z provider IP where my mailserver IP 212.x.y.z is routed to

2) Synology DiskStation LAN1 with mailserver running on 212.x.y.z  (on port RV345P's 16) and LAN2 with 192.168.1.100

Tried different settings on the RV345P and I could ping 212.x.y.z but not telnet to the SMTP port. Obviously it was the RV345P itself responding and not the DiskStation (I unplugged it and it still responded).

What do I have to do to make 212.x.y.z with it's mailserver available?

Do I choose Host DMZ or Hardware DMZ? Which IP do I have to enter? Anything else to setup (VLAN,...)?

Thanks a lot!

[balaji.bandi]

follow below document to help you setup one - still not working post the screenshot.

https://www.cisco.com/c/en/us/support/docs/smb/routers/cisco-rv-series-small-business-routers/Configuring_DMZ_on_the_RV34x_Series_Router.html

[sicher]

Thanks, I already know this document which I based my questions on.

The DiskStation is configured as 212.x.y.z. The RV345P gets the 80.x.y.z via DHCP from the provider.

Is there another setting beside the DMZ hardware or DMZ host? Which one should I use? Where to put the IP 212.x.y.z? Any VLAN settings tome it work?

[balaji.bandi]

The DiskStation is configured as 212.x.y.z. The RV345P gets the 80.x.y.z via DHCP from the provider.

80.X.X is pulic IP where external people accessing - this should be DMZ outside

212.x.X (this is also public IP, not sure is this allocated by ISP or you own it) - generally internal host will be RFC 1918 address space. to hide from public network for security reason, that is the reason we setup DMZ zone.

if 212.x.x. is your host IP address, then you need to map 80.x.x.x to 212.x.x.x

here is Flows :

Internet users -------your ISP-------DMZ--Internal LAN (your host where services hosted )

is this make sense ?

[sicher]

Thank you!

After entering the public IP 212.x.y.z in BOTH, DMZ Hardware and DMZ Host, the mail server can be accessed from outside.

BUT I can't connect from the LAN, i. e. from 192.168.1.101 to 212.x.y.z even when the firewall on DiskStation is disabled. Access to the internet works though.