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Bus 001 Device 002: ID 148f:2570 Ralink Technology, Corp. 802.11g WiFi
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 0 (Defined at Interface level)
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x148f Ralink Technology, Corp.
idProduct 0×2570 802.11g WiFi
bcdDevice 0.01
iManufacturer 1 Ralink
iProduct 2 802.11g WLAN
iSerial 0
bNumConfigurations 1

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i knew that centos has rt2500usb module build in as module in the kernel itself and it’s loaded automatically when booting up, but the strange thing i cannot associate with any ap that is working fine with other wifi adapter, i thought there must be something wrong with the kernel, because i’m using a non usual kernel on my machine , it’s a “2.6.18-128.1.1.el5.028stab062.3PAE” , it’s a openvz kernel , but it was gave the same results when i boot up with standard kernel

wlan0: authentication with AP xx:xx:xx:xx:xx:xx timed out
and
something like cannot associate to the AP itself

had several times googling and here are the solutions, quite simple solutions in fact
-)download the new driver, looks like there are some incompatibility/bugs with the current driver,
drivers are downloadable through http://www.ralinktech.com/ralink/Home/Support/Linux.html
and compile it
-)prevents current driver being activated during booting, just simply put the module into /etc/modprobe.d/blacklist, it should be something like this
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blacklist rt2500usb
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-)#reboot
-)check the module whether the new module/driver brought up after rebooted
rt2570 163712 0
-)check if there any new interface appearing after executed ifconfig -a
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rausb0 Link encap:Ethernet HWaddr 00:00:00:00:00:00
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
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wala!!!, all seems to be working perfectly , after it’s can associated with the AP , and got the ip address by using dhclient

Reference:

http://harusharris.blogspot.sg/2009/08/compex-wlu54g-finally-on-centos-52.html