realtek 8187b driver and 9.04

[feh]

Hi folks.

I'm running mythbuntu 9.04, but I assume this would be the case for any variant...I'm having problems with a Trendnet 424UB wireless adapter.

It uses the realtek 8187 chipset. The driver (which is part of the 9.04 install - I didn't download anything) seems to be aware of the card. All iwconfig commands work; I can configure the adapter.

The problem is that when I run dhclient, I don't get an address.

Is this a known problem? How do I troubleshoot the situation?

Thanks!

[coffeeaddict22]

Hi,
Nice article here from a month ago that might help.

[feh]

Hi,
Nice article here from a month ago that might help.

Thanks for the link, but this isn't a general "the internet is down" type of problem. It's either a problem w/ the Realtek 8187b driver, or my dhcp client (or the kernel).

[coffeeaddict22]

if it was the kernel/ driver, iwconfig would be down. So it's likely your network connections. what happens when you try to ping? And what does

route -n

show?

[feh]

if it was the kernel/ driver, iwconfig would be down. So it's likely your network connections. what happens when you try to ping? And what does

route -n

show?

I agree that the kernel/driver is probably ok, since I'm able to configure the interface.

I can't ping anything and the routing table is empty, because dhclient isn't able to get an IP address. I've got other machines on the same network (including another linux machine using the same adapter), so I don't believe it's the wifi router.

[coffeeaddict22]

So what does iwconfig show? And what do you get from

sudo iwlist scan

[feh]

So what does iwconfig show? And what do you get from

sudo iwlist scan

I'm not at the machine now, so I'll have to summarize:

iwconfig shows my wlan0 interface as you would expect on a working system. I set the options manually, using iwconfig commands.

iwlist scan does show a network (with hidden ssid), which is my home network.

Everything looks good on the surface, but dhclient doesn't get an IP address.

[coffeeaddict22]

Yeah, but what's the driver? There's been a few issues with wireless drivers not getting picked up right; the clue is that wmaster0 is listed as a link, and it hijacks the working driver; wlan0 ends up with some other driver, often a leftover ndiwrapper or a dummy.

[feh]

Yeah, but what's the driver? There's been a few issues with wireless drivers not getting picked up right; the clue is that wmaster0 is listed as a link, and it hijacks the working driver; wlan0 ends up with some other driver, often a leftover ndiwrapper or a dummy.

The wireless network is listed under wlan0 in the "iwlist scan" output. Does that answer your question?

If not, how would I determine which driver is being used for each interface?

Thanks.

[coffeeaddict22]

The only place the driver is easily accessible and reliably listed is in

lshw -C network

Nearly everywhere else you look uses the logical name to categorise the output, so you need to look in lshw to confirm which driver is linked to which logical name.

Having said that, sometimes you've got to look through the output of

lsmod

to make sure there isn't another driver interfering. The latest upgrade in particular seems to have created some issues; I think part of the problem is ndiswrapper was needed for many cards in 8.04/ 8.10, and inserting ndiswrapper drivers was a bit of a workaround- so they remain installed when you upgrade, even if the new kernel senses your card and installs the correct driver.