W10 cannot ping W7, W7 can ping W10 - ALL firewalls already disabled

[nicky9499]

Hi guys,

 

I'm having to deal with another one of those truly idiotic moments when Windows network shares decide to completely break down for no goddamn reason whatsoever. In this case, my W10 workstation cannot access the W7 server. The W7 server can ping the W10 (and everyone else on the network). Obviously this not being the first time this dumb shit has happened, just about every security cut-down you can think of has already been done.

 

- No password sharing.

- 40-bit encryption

- Insecure guest logons allowed

- Digitally sign communications disabled

- Just about every single measure outlined here

 

Now I'm back to basic testing, and it turns out W10 can't even ping W7.

So I tore down both firewalls AND the router firewall, and it is still not working.

 

I am at my wits' end. I need to work and I need to move files, I cannot be running all over the house with goddamn flash drives all day long.

Can someone please advise what else can one do to force a connection through?

(Other than setting up something completely non-shared-folder like FTP and even so that might not work seeing how they can't even get a bloody ping on each other.)

 

Thank you in advance.

 

 

[Master Disaster]

Can 10 ping your router and does it have access to the internet?

[nicky9499]

36 minutes ago, Master Disaster said:

Can 10 ping your router and does it have access to the internet?

 

Yes, it can. And yes, I do have full internet access. Wired.

 

 

 

For what it's worth these two machines have two paths to get to each other:

1. Regular CAT6 cable via a HP Enterprise switch and Linksys router. This is also how we get to the internet.

2. Pair of Mellanox ConnectX2 connected directly with a long SFP cable with all the relevant prioritizing setups.

Basically straight out of Linus' tutorial.

 

Needless to say both were working flawlessly (most of the time) up till now.

[Master Disaster]

Hmm, does your client have 2 NICs? Also really dumb question but did you check both machines are in the same workgroup?

[nicky9499]

Edited the above post with NIC information.

 

Not dumb at all, I've done that before too during a previous "can't connect" episode where resetting everyone back to the default "WORKGROUP" workgroup fixed the issue. So both are on "WORKGROUP" right now. Nothing fancy.

[Master Disaster]

Wow, that's a REALLY nice setup for your home, I'm a little jealous

 

Seems like I'm preaching to the choir here (as in you seem to be incredibly knowledgeable in this stuff already and anything I suggest is kinda superfluous) but did you do the old...

 

ipconfig /release

ipconfig /flushdns

netsh winsock reset

then reboot

 

...trick?

[nicky9499]

Here's another overview of the situation.

[Master Disaster]

3 minutes ago, nicky9499 said:

Here's another overview of the situation.

Comparing both screenshots I think I see the issue

 

You LAN NIC on the client has an invalid IPV4 address - 169.254.xxx.xxx - It doesn't seem to match any of your subnet ranges.

[nicky9499]

4 minutes ago, Master Disaster said:

Comparing both screenshots I think I see the issue

 

You LAN NIC on the client has an invalid IPV4 address - 169.254.xxx.xxx - It doesn't seem to match any of your subnet ranges.

This is the ticket. I manually set them to something appropriate, leaving default gateway blank and DNS servers just randomly filled in - it fails validation but since this connection doesn't connect to the internet, that's fine. Surprisingly, after applying this change, both the RJ45 and SFP connections can be pinged from W10 to W7. The weirdness of Windows, whatever.

 

With my deepest sincerity - thank you, good sir.