nigerian wrote

My previous thread has been deleted for some reason, why?

First post always appears only after a moderator did approve it. There is indeed a double post now.

What is connected:
Port 1: Windows PC (affected)
Port 2: PS4 (works fine)
Port 3: Raspberyy Pi (works fine)
Port 4: Windows PC (affected)

What makes you sure that the switch causes the outages?

Did you check wether your Windows PCs lose Internet too, if connected on ports 2 and 3 of the switch?

Do the Raspberry Pi and PS4 still not lose Internet even if connected to ports 1 and 4 of the switch?

nigerian wrote

Yeah the message went away really fast and I thought it was removed, I reported the other post.

No problem. You could just delete it, but never mind.

I've tried with multiple ports to be sure and I still get these disconnects.
And yes I tried it with my Pi and PS4 on the other ports so yeah :O

If net access keeps going down while connecting the PC to ports which formerly were stable with the Pi/PS4 and if the Pi/PS4 have continuous net access on ports formerly making problems with the PCs, it's definitely not a malfunction of the TL-SG108 switch, but a problem located elsewhere.

Try to set a static (fixed) IP on your PC, make sure it's an unused IP, i.e. outside of the DHCP range of your router/DHCP server.

If the effect of losing net access disappears with a static IP, it is a DHCP problem (maybe two DHCP server running simultaneously?).
If not, I have no idea what causes Windows to drop net access from time to time.

Why did you put the PC in a DMZ? What purpose serves the firewall on your PC? Why do you use two different static IPs on your PC? Looks like a very weird setup to me. But definitely ping delays are caused by this firewall running on your PC.

nigerian wrote

"Give here the LAN IP from the pc that needs to be connected with the internet immediatly." and I just put my PC there since I can't leave it blank.

So you configured it in the DMZ. Depending on how the router handles a DMZ zone, this could be the cause for your troubles.

The firewall from my router you mean? It blocks unwanted traffic and I've never disabled it. Do you recommend to disable it since idk couldn't it be a security risk? (i might block ddos attacks too).

Never ever disable the firewall of your upstream router. It is there to protect your LAN from accesses through the Internet. But port forwardings to PCs in LAN belong to the upstream router, not to the PC itself. Depending on how your router works, a DMZ zone is usually exposing the hosts in the DMZ to the Internet, so you would have to disable every service not to be exposed to the Internet on such hosts.

Of course you could try to disable or block such services on each PC's firewall, but IMHO this is a medium nightmare.

Personal firewalls are not very reliable, since they run on the same system they should protect it at first. Therefore, firewalls belong to routers or even to stand-alone hardware used for just firewalling, but you should not run standard applications on it. Furthermore, if your PC's is busy with a CPU-intensive application such as graphics running on it, it can't do firewalling or routing at the same time and this is why you experience drops in connectivity or in pings.

I would recommend to move the PC to the LAN (not DMZ), to forward any ports on your router you need for gaming to the local PC in this LAN and to disable the firewall toy on your PC (but never do so on the upstream router). That would be a much more cleaner setup.

But this has nothing to do with the TL-SG108, so it is kind of becoming off-topic here. Maybe in gamer's forums you will find more help on how to cleanly setup a PC used for gaming with the need for certain ports open to access from the Internet.