DM200 port forwarding only works on some ports?

[The_Obo]

I have recently purchased a Netgear DM200 to replace my rubbish Vodafone modem/router.

It has the latest firmware (V1.0.0.61)

I am using it in Modem/Router mode and as a DHCP server.

Setup was pretty good (apart from the missing NAT Loopback) and I have used reserved IP Addresses for most of my servers, cameras and other devices that need port forwarding.

The weird thing I am finding is that some ports don't apear to be forwarding.

For instance I have 3389 forwared to a machine for RDP and it works fine.

But I have 8181 also forwarded to the same machine and it will not work.

I also have 1001 forwarded to my alarm system and it works fine, but 110 forwarded to my lighting system will not work.

They are all setup the same, and all work inside the LAN (using local IP Addresses because the NAT Loopback doesn't work)

They are all also "see-able" via canyouseeme.org port checking tool.

Any ideas why?

[schumaku]

@DexterJB  exactly the issues we faced (already a long time ago) on the DM200 what made us phase out the DM200 and replace by ZyXELs - issue exist in both router and oddly in modem mode.

[The_Obo]

Which ZyXEL model do you recommend?

[schumaku]

Afrid, my bad for mentioning another brand name - I'm a little bit holding back with this usually. Here in Switzerland, we have excellent coverage and support for ZyXEL xDSL by the distributor, Studerus.ch - different markets might have different requirements. You can PM me.