HALP! Changed Public IP...internetz broke

Hi all,

My modem was reporting DDOS attacks from China in the logs. Wasn't affected due to firewall.
I changed my Public IP address in the modem by copying the Dynamic settings and adding them to Static IP. I then changed the Public IP in Static mode by 1. After a reboot, I switched back to Dynamic IP. Was issued a new IP from my ISP.

My problem is this - all my PCs (Linux & Windows, Wired & WiFi) are able to connect and browse web-pages properly, speedtest.net reports full speed. Youtube doesn't work though. Can't view teksyndicate videos. Steam and all other game clients won't work now. Any program using its own software to connect to an account doesn't work. Only the web browser. My Android phone's WiFi connection works fine. Youtube app works, youtube videos in mobile browser works, steam works, unlike PCs. VPN doesn't work on PCs or Android though...

I have done a factory reset on the modem, still have my new Public IP (which I want, but internet no longer works properly). Been trying to fix this for hours.

I have cable internet. Have I made a big boo-boo? I was thinking perhaps my ISP needs to re-authenticate my modem...but my phone works fine :(

How did you preform the factory reset?

And I am unaware of a modem that has that kind of log. Unless it is A wireless modem?

I held the factory reset button for 30 seconds with a toothpick. I do them every other month and redo my settings, don't think that is the issue.

The connection was broken after the Public IP change, but before the factory reset. I reset thinking it would trigger re-authentication with ISP.

Yeah it is a wireless modem. Log was filled with "Teardrop/DDOS detected" with the same IP... 14.xxx.xxx.xxx

Did you unplug it from power for like 5 minutes, this should force it to get all new settings from the ISP. Look for a firewall setting, the reset may have turned it back on or upped the security level blocking steam and other apps.

If you get internet it is not an issue with the isp, its a setting somewhere.

those logs happen all the time just ignore them unless you are suffering internet slowdowns.

example my log with no internet issues.

Yeah I left it off for half hour after the reset, and turned off the firewall just to see.

Reinstalled WiFi adaptor on PCs, did "ipconfig /release" "/renew" "/flushdns", "netsh winsock reset catalog", "netsh int ip reset reset.log"

Also called ISP for some scripted responses...

Modem settings are the exact same as before (when I factory reset only thing to do is add my forwarded ports again), all I did was copy/paste Dynamic IP settings in to Static IP then switch back for a new Public IP... could it be a MAC address issue since my phone is fine but PCs aren't?

All service works fine on the phone correct? which is on the wifi

which means its issues with the pcs not the internet.

try setting the default dns to like googles or something 8.8.8.8

Have you restarted the computers? I know obvious but still.

Yeah restarted them all. Everything on phone is fine except VPN no longer works...just like PCs.

Was using OpenNIC DNS. Removed that and did "ipconfig /flushdns" to revert to ISP's DNS but that didn't help. One of my machines hasn't had its DNS changed and that isn't working properly either.

Google's DNS fixes the youtube problem, but game clients like Steam still aren't working...

Then there has to be a firewall issue somewhere. Exact problem happened to my dad. and was a firewall blocking ports steam needed.

It's off on the modem. Turned off Windows firewall to no avail, and haven't installed any firewall software in Ubuntu...

Now that I'm watching Youtube and browsing more, the net is choppy on both phone and PCs...

Is there some kind of QoS turned on now on the wireless modem?

Can you even log on to steam? does it give a reason as to why not?

That option is missing from the modem my ISP supplied...as are heaps of other settings like DNS. Probs makes it easier for them to spy on customers :(

What type of wireless modem is it and from what company is your isp?

Hmm, I am kinda out of idea's. It seams like something is blocking steam but if the firewall is off i am not sure what is.

only thing i saw in a manual was port blocking and service blocking. idk if anything is in those on default(shouldn't be)

you can try turning on upnp if it is not already on.

or maybe something under services tab

manual im using https://www.ono.es/resources/files/ayuda-y-soporte/internet/equipos/documentacion/Netgear/MTA_CG3100/MTA_CG3100_UM_ING.pdf

Yeah everything appears as it should be...upnp is on.

After a factory reset, everything usually works "out the box" so I'm at a loss as to what it could be. Maybe my ISP needs to "approve" the new IP. Steam downloads don't count towards my monthly usage so perhaps its all part of their process.

Thanks heaps for your help anyway. Will report back tomorrow with solution, or whenever I get it fixed.

No problem.

FYI. All modems should have logs. Also don't bother trying to change your IP because China is knocking on the door. It won't make a difference, They attack all public IPs every minute of every day. Your firewall should be on and doing its job.