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Question

Find out the ports that a device is using by sniffing

by Dec 6, 2016 8:23AM PST

Hello,

My ISP provided me with a Router/Modem, which I have no access on it. They informed me that all the ports on LAN1 are open. So if I want to say hi to the outside world I have to use LAN1.

I have an energy Inverter System which needs to be connected to the outside world to send analytics about the energy it saves etc.

So, on LAN1 of my ISP Router I connected my DLink 655 router and then from my router I connected my 24port Switch. In theory now I have the control of my network, with my dlink router in between, right?

I tried to find on the net the ports that the inverter is using and open them on my router, but the inverter cant communicate with the outside world unless is connected straight to my ISPs router on LAN1.

I even tried to use DMZ on the Inverter no luck. Is there any way to sniff the inverters traffic and see which ports is using and tried to make it work behind my router?

I want to put my webserver out but I cant, cause I have to leave the inverter out which is a No~No.

Discussion is locked

3 Posts
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Clarification Request
About that 655.
by r. proffitt Forum moderator Dec 6, 2016 8:46AM PST

" So, on LAN1 of my ISP Router I connected my DLink 655 router "

Is that a router or a "Router as a WAP"?

If it's a router I can't help you. If it's a WAP then it should be fine. Remember it's my choice to never support 2 routers (or more) one behind each other. That setup rarely works and is far too finicky for everyday use.

https://www.google.com/search?q=port+sniffing&ie=utf-8&oe=utf-8 finds too many priors on port sniffing. I don't know if you have the gear to do this.

As to what ports the energy reports on, that would be a question to its maker and far less work than setting up port sniffing boxes, PCs and apps.

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About Router
by BobbysCY Dec 6, 2016 9:03AM PST

My ISP is using somekind of a Telsey CPVA 624 moded to their brand name..there is no access to their control panel. In order to change lets say WiFi Password or enable/disable wifi broadcast you have to give them a call. I wont say its a router, I would say its more a modem to me.

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My question was about the 655
by r. proffitt Forum moderator Dec 6, 2016 9:33AM PST

Not the 624. So while you repeated the 624 is not for you to fiddle with I can't tell if your 655 is a router or a "router as a WAP."

As a router I can't help. It's a tar pit of issues and unsupportable.

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