hostap AP connected but cannot ping

[Uday Yeddula]

Hi David,

Thank you for replying.

Yes, I have assigned ip-address to the wireless interface in AP mode.
As I wrote in my previous e-mail, when I ping from my laptop to the device
in AP mode, the device responds to the ARP requests and the ICMP echo
requests with ARP replies and ICMP echo replies. But, the replies are not
received by my laptop.
The "tcpdump" captures on the wireless interface in AP mode, when an ICMP
request is sent from my laptop are as below:

====> when ARP entry for the wireless interface in AP mode is not present in
my laptop,
*user at user:~$ sudo tcpdump -i wlan2
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on wlan2, link-type EN10MB (Ethernet), capture size 96 bytes
11:17:58.729002 ARP, Request who-has 172.16.1.1 tell 172.16.1.11, length 28
11:17:58.729024 ARP, Request who-has 172.16.1.1 tell 172.16.1.11, length 28
11:17:58.729033 ARP, Reply 172.16.1.1 is-at 00:26:b6:de:f3:9b (oui Unknown),
length 28

=====> when ARP entry is present on my laptop
user at user:~$ sudo tcpdump -i wlan2
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on wlan2, link-type EN10MB (Ethernet), capture size 96 bytes
11:23:53.568172 IP 172.16.1.11 > 172.16.1.1: ICMP echo request, id 11220,
seq 15, length 64
11:23:53.568222 IP 172.16.1.1 > 172.16.1.11: ICMP echo reply, id 11220, seq
15, length 64
*
So, suspecting either the packets are lost in air or mishandled by the
wireless driver (ath9k + hostapd).
Any thoughts on this?

Thanks,
Uday.

On Sat, Jun 11, 2011 at 9:39 AM, Davide <louigi600 at yahoo.it> wrote:

> Have you given your wireless interface in AP mode an ip address ?
> If you don't do that you will not be able to ping it.
> You could also try bridging lan and wlan in one virtual interface allowing
> bothe to be seen with the same address.
>
> Regards
> David
>
> --- *Ven 10/6/11, Uday Yeddula <uday.yeddula at gmail.com>* ha scritto:
>
>
> Da: Uday Yeddula <uday.yeddula at gmail.com>
> Oggetto: hostap AP connected but cannot ping
> A: hostap at lists.shmoo.com
> Data: Venerd? 10 giugno 2011, 12:50
>
>
> Hi,
>
> I am trying to configure an embedded device as an Access Point. It has
> Atheros Communications Inc. AR928X Wireless Network Adapter (PCI-Express). I
> have Ubuntu 9.10 Server version installed in the box. ("2.6.31-14-generic
> #48-Ubuntu SMP"). Using hostapd deamon with ath9k driver for the same.
>
> I have built hostapd using libnl-dev and libssl-dev packages.
> After starting the hostapd with the hostapd.conf (sudo ./hostapd
> hostapd.conf), tried connecting my laptop to this AP.
> The connection was successful but cannot ping from my laptop to the AP.*
>
> user at user:~$ sudo hostapd /etc/hostapd/hostapd.conf
> Configuration file: /etc/hostapd/hostapd.conf
> Using interface wlan2 with hwaddr 00:26:b6:de:f3:9b and ssid 'test'
> wlan2: STA 00:26:82:c9:d3:30 IEEE 802.11: authenticated
> wlan2: STA 00:26:82:c9:d3:30 IEEE 802.11: associated (aid 1)
> wlan2: STA 00:26:82:c9:d3:30 RADIUS: starting accounting session
> 4DF1F33A-00000000
> *
> On further analysis found that, my laptop sends the ARP request to the AP
> box. The AP box sends the ARP reply (observed using tcpdump on the AP box)
> but my laptop cannot see the ARP reply.
> If I restart hostapd deamon at this point, it works fine. (My laptop can
> ping the AP).
> The AP is not stable. my laptop can always connect to it. But some times
> the ping to the AP fails.
>
> Has any one seen similar issue? Can you help me with the fix for this
> problem?
> I have tried both hostapd-0.6.9 and hostapd-0.7.3 versions and found same
> problem on both versions.
>
> The hostapd.conf used is as follows:
>
> hostapd.conf:
>
> interface=wlan0
> driver=nl80211
> ssid=test
> channel=11
> hw_mode=g
> macaddr_acl=0
> auth_algs=0
> ignore_broadcast_ssid=0
>
> Thanks,
> Uday.
>
> -----Segue allegato-----
>
> _______________________________________________
> HostAP mailing list
> HostAP at lists.shmoo.com <http://mc/compose?to=HostAP at lists.shmoo.com>
> http://lists.shmoo.com/mailman/listinfo/hostap
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.shmoo.com/pipermail/hostap/attachments/20110613/655ddf3f/attachment-0001.htm