Possible SYN flooding on port 8200. Sending cookies.

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umrico

New Around Here
Good Day,

I keep getting the following a couple times a minute and I can't figure out what it is for the life of me. How can I troubleshoot this? TIA for your help it is greatly appreciated!!!

Feb 13 18:58:17 kernel: TCP: Possible SYN flooding on port 8200. Sending cookies.
Feb 13 18:58:17 kernel: TCP: Possible SYN flooding on port 8200. Sending cookies.
Feb 13 18:58:22 kernel: TCP: Possible SYN flooding on port 8200. Sending cookies.
Feb 13 18:58:22 kernel: TCP: Possible SYN flooding on port 8200. Sending cookies.
Feb 13 18:58:22 kernel: TCP: Possible SYN flooding on port 8200. Sending cookies.
Feb 13 18:58:22 kernel: TCP: Possible SYN flooding on port 8200. Sending cookies.
Feb 13 18:58:22 kernel: TCP: Possible SYN flooding on port 8200. Sending cookies.
Feb 13 18:58:22 kernel: TCP: Possible SYN flooding on port 8200. Sending cookies.
 

ColinTaylor

Part of the Furniture
Router model?
Firmware version?

Do you have the router's Media Server enabled? Have you disabled the router's firewall?
 

umrico

New Around Here
Router model?
Firmware version?

Do you have the router's Media Server enabled? Have you disabled the router's firewall?
Rt-ac-68u

FW 384.15. it's happened on at least the last 3 versions that I have noticed anyway.

Upnp media server was turned on. I don't recall flipping that on. That may have instantly solved the problem.A that's the problem, why would that be?

Firewall is on.

Thanks again for you help! Googled this forever and tried running a wireshark but couldn't see the problem!
 

ColinTaylor

Part of the Furniture
A that's the problem, why would that be?

Firewall is on.
If the firewall in on then I can only assume that something on your LAN is spamming the media server. To discover what you'd have to run tcpdump on the router, or systematically turn each device on your LAN off until you find the culprit. I'd suspect devices like smart TV's or media servers (e.g. Roku, AppleTV, etc.).
 

umrico

New Around Here
If the firewall in on then I can only assume that something on your LAN is spamming the media server. To discover what you'd have to run tcpdump on the router, or systematically turn each device on your LAN off until you find the culprit. I'd suspect devices like smart TV's or media servers (e.g. Roku, AppleTV, etc.).
Thank you so much for your help i appreciate!
 

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