Cannot see/ping computers on workgroup

[andressito]

Hi,

I'm trying to set my home network, but i'm having some problems.

I can't see or ping the computers on the same workgroup.

The network has a Win7 laptop, a Win7 desktop, a Vista laptop and a XP desktop.

I don't care so much for the Vista and XP, computers, but I'd really like to set the network running ok between the Win7 computers.

- I'm using a wireless network, with DHCP (using address reservation by MAC)

- They are all on the same workgroup.

- All of them can access internet just fine and they can ping the network printer and the gateway.

- Network discovery is turned on, on both win7

- File/printer sharing is on also, so LAN rules are ok on Windows Firewall

- I've unchecked "use sharing wizard"

- Homegroup is not set on neither.

- I've tried with NetBIOS over TCP/IP enabled and disabled

- Pinging computers (including Vista and XP) always return "Destination Host Unreachable"

I've checked all of this by reading other forums/sites, but i still can't figure what is wrong, so any help, suggestion, tests/checking is appreciated!

[Roger H. Veteran]

Do you have any other firewalls installed from some security suite?

[andressito]

  On 29/08/2011 at 17:10, SHoTTa35 said:

Do you have any other firewalls installed from some security suite?

Nope... just Windows Firewall, which I've tried to turn off to test, but no luck

[sc302 Veteran]

what security software do you have?

[andressito]

  On 29/08/2011 at 17:27, sc302 said:

what security software do you have?

I'm using Avira free on both computers.

[sc302 Veteran]

do you have wireless isolation enabled in your router/access point?

this feature disables communication between computers on your wireless network.

[andressito]

@+sc302

My router doesn't seem to have this option (even though it is in the manual, but the manual is also for another model).

But it looks like the default state is disabled.

I need to check it better, because it makes a lot of sense...

Thanks!

[sc302 Veteran]

what make/model do you have?

[+PeterUK MVC]

Put in \\ and the IP (e.g. \\192.168.0.3) in the network address bar of the other computer and hit enter.

[andressito]

  On 29/08/2011 at 18:15, sc302 said:

what make/model do you have?

TP-Link TL-WR941N

I found the wireless > wireless advanced tab, but there is no "enabled AP isolation" option like it says on the manual.

I need to see if there is another way to check this settings, and see if this option really exists in this model

[+BudMan MVC]

Ok just so we are all on the same page, what workgroup machines are in would have nothing to do with simple ping test. It would have nothing to do with anything other than where machines would be listed in the browselist. Not used for security at all, just simple browse listing location is all.

As to ping, and the windows firewall by default it would block ping.. As to turning it off, did you just set it to off or did you try disable it?

Make sure your rules are set to all all inbound on the firewall, and I would verify you have allowed icmp. The sure you can turn it off.

When you try and ping

"- Pinging computers (including Vista and XP) always return "Destination Host Unreachable""

Are you pinging by name or by IP? Make sure you are using IP for verification, if netbios over tcp is not enabled you might not be broadcasting for name. Depending on what your node type is, you might not broadcast for name, etc.

Once you ping by IP, take a look at your arp table

arp -a

Do you see the MAC of the device you tried to ping - is it valid? or all zeros? If all zeros never going to work, and that might point to a AP isolation thing. If you get the correct mac for the ip your trying to ping - you can verify this with ipconfig /all on the computer your trying to ping to see what its mac is.

And your sure no firewall blocking, double check that AP isolation setting. That being on for sure would prevent your wireless from talking to each other.

So ping by IP, and then check arp table -- this will give us good info to work with on where to look to what the problem is.

[andressito]

@BudMan

Hey there! You've helped me a while ago with a network problem in my work place, and i hope we can solve this one also!

I've turn the firewall off, but i've checked the rules and there is an inbound rule allowing icmpv4 request (set by flie/printer sharing)

I always ping by IP.

Checking the arp table, the IP i'm trying to ping doesn't show on the list

Since nobody can't see/ping nobody, I think it is the AP isolation like sc302 said, but i can't find if this is enabled or not.

If i enter the configurations for the router (by IP on the browser), i can't find where it is stated on the manual.

I'm checking if there is another way to check this settings.

[sc302 Veteran]

perhaps either a firmware update or update to dd-wrt will help. your router is listed as supported by dd-wrt.

[+BudMan MVC]

so you see no arp entry for that IP right after you try and ping it? or do you see zeros for the mac?

Yeah kind of hard to ping with out a mac to send the traffic too ;)

What specific router are you using?

is that v2 or v3 of the TL-WR941ND, its a ND right not just N -- I don't see just a N

[andressito]

  On 29/08/2011 at 18:52, sc302 said:

perhaps either a firmware update or update to dd-wrt will help. your router is listed as supported by dd-wrt.

I'm thinking this might help =)

@BudMan

I can't see the IP entry... if it is all zeros, i remember i can set a mac address to it =)

I'm using TP-Link TL-WR941N

[andressito]

@BudMan

Well, the title says TL-WR941N =)

If you see on the upper right of you screenshot it applies for the N and ND model

I checked the versions:

Firmware Version: 2.1.2 Build 080321 Rel.63639n

Hardware Version: WR941N v2 00000000

The last option on this page is the "Enable Short GI"...

But the screenshot you've sent is different than mine, so I will try a firmware update and see what happens

[+BudMan MVC]

I show the firmware as

Firmware Version:

3.11.0 Build 100325 Rel.32271n

Hardware Version:

WR941N v2/v3 00000000

On that emulator

[andressito]

Good and bad news...

I guess it was the isolation issue.

'I guess' because i'm in a secondary network now, that have this option explicit and disabled, and the network/ping is fine.

But I'm on this other network because my main router stopped working after the firmware update =P

Gonna buy a new one...

It was a fairly simple problem, but i didn't know this ap isolation setting...

Thanks everyone!

[sc302 Veteran]

sux that it bricked. :pinch:

[andressito]

  On 29/08/2011 at 20:27, sc302 said:

sux that it bricked. :pinch:

It's back up!!!

I took i while, but i tryed one more time (i wasn't going to buy today anyway).

The win7 detected the router and let configure using the PIN. I wasn't working, but after 1 hour, it entered the config page!

I guess the firmware update is really slow =)

Now, with that option disabled, everything is working fine!!

I just don't know how they make a router with this setting on by default and no option to change it... =P

Thanks again everyone!!!

[+BudMan MVC]

Yeah that AP isolation thing causes people that don't know about it grief all the time ;)

Clearly not something that should be enabled by default on a home type router, but it is very good security feature for say a coffee shop or something where you have lots of guest and don't want them talking to each other over the network because of security concerns.

Another term for it is client isolation, which is better term if you ask me. Also wireless isolation is another term. Some routers allow for isolation between clients on different SSIDs - more modern AP provide for multiple SSIDs so you can do some better isolation and have like a private wireless network and than a guest one where you only have access internet for example.

It still does not protect you from someone that is on the wireless network in sniffing the traffic, but would keep say an infected box hitting your box with worm traffic for example.