I think of myself as an advanced user but this problem is driving me batty.
Windows XP (32bit Home) going through a WRT54G router, once or twice a day at completely different random times, refuses to connect to my main webserver on any port for a random amount of time, a few minutes to as long as 15+ minutes. Every other site works fine.
Here are the tricky catches though when this starts happening:
- Everyone else around the world can still connect just fine
- The router can directly connect (via shell I can wget, ssh etc)
- ping/traceroute WORKS from Windows - only http, ftp, ssh timesout (so UDP works?!)
- plug a netbook into the same router, the netbook CAN connect
- The webserver has several IPs - NONE of them connect when it starts doing this
- if I already have a ssh connection when this starts, IT WORKS, only new connection blocked
- I can connect to any other website/http/ftp just fine when this happens
- ipconfig /flushdns does NOT solve the problem (direct IP doesn't work either)
So, in summary, UDP seems to connect when this starts happening but not tcp/ip, router can talk to the webserver but not Windows.
So the router is either blocking TCP/IP from at random times from my PC to several different IPs but no others. Or Windows is refusing TCP/IP outbound to these specific IPs but not others for random times.
Can you spot anything else I should be looking for or trying?
added: discovered that resetting the Windows TCP/IP stack immediately allows me to re-connect to the server
netsh int ip reset
so it's something related or attached to the tcp/ip stack - but of course resetting it might cause other drivers or layers to also reset (windows firewall is not active)