wireless access point in FreeBSD 8.2p2

Paul Beard paulbeard at gmail.com
Sun Aug 28 16:22:43 UTC 2011

On Aug 28, 2011, at 7:04 AM, CyberLeo Kitsana wrote:

> It is especially useful when you cannot ping, as it can tell you if the
> packets are even arriving.

The "no route to host" result makes me think the packets aren't going far ;-) The new device and the wired interface are at adjacent numeric addresses and all the devices here are in the same subnet behind the WRT54G and that is behind the cable co's black box. 

I think I may be more confused now than when I started. 

One thing that has seemed opaque to me is that both ath0 and wlan0 display when I run ifconfig and look very similar: makes me think they might be stepping on each other. Or it's just one more thing I don't understand :-( 

ath0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 2290
	ether 00:0d:88:93:21:3a
	media: IEEE 802.11 Wireless Ethernet autoselect mode 11g <hostap>
	status: running

wlan0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	ether 00:0d:88:93:21:3a
	inet netmask 0xffffff00 broadcast
	inet6 fe80::20d:88ff:fe93:213a%wlan0 prefixlen 64 scopeid 0x8 
	media: IEEE 802.11 Wireless Ethernet autoselect mode 11g <hostap>
	status: running
	ssid lower channel 8 (2447 MHz 11g) bssid 00:0d:88:93:21:3a
	regdomain FCC indoor ecm authmode OPEN privacy OFF txpower 27
	scanvalid 60 protmode CTS wme burst dtimperiod 1 -dfs

I know (or think I do) that ath0 is the real interface and wlan0 is a virtualized or cloned or something handle to it. But the similarities (both are running, both show the same info for media) trouble me. The only thing that makes me think I'm doing anything here is that wlan0 is actually assigned to channel 8. 

I can sort of see that getting it working as a client would be instructive and I think I did that some time ago (perhaps in 7.x) but since you reuse almost nothing but the hardware, I don't see a lot of value in that, other than verifying that the hardware works and that you can follow the instructions. The latter can be a challenge, I'll admit. 

So to recap: the idea of this was to provide a redundant spare for the WRT54G, behind a cable modem, in a private network, with the only security being at the AP
	• No ipfw or any of that, as it wouldn't be visible on the public internet.
	• I'll add WPA/2 once it works (that seems trivial, as I have been able to authenticate to the AP even though it didn't pass any packets beyond that). 
	• It would deal with static addresses (I could add dhcp later, once this was working, as phones and other devices are more easily dealt with that way). So it looks like a bridge, if it joins an Ethernet network and an 802.11-based one. Curiously, none of the instructions I have seen mention bridging, even though the explicitly connect Ethernet and wireless. And all the HOWTOs look simple, the work of a few minutes of copy and paste. 

I think I may just shelve this and if needed, turn up my Time Capsule's wireless capability (if it would play nicely and extend the WRT54G, I'd be using it now). And APs that support open source firmware are not that hard to find, though Tomato doesn't support as many as the *-wrt variants. 


Paul Beard

Are you trying to win an argument or solve a problem? 

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