Return-path: Received: from mail-wm0-f46.google.com ([74.125.82.46]:36518 "EHLO mail-wm0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758811AbcDENZL (ORCPT ); Tue, 5 Apr 2016 09:25:11 -0400 Received: by mail-wm0-f46.google.com with SMTP id 127so24496753wmu.1 for ; Tue, 05 Apr 2016 06:25:10 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <0BA3FCBA62E2DC44AF3030971E174FB32EAA379D@hasmsx107.ger.corp.intel.com> References: <0BA3FCBA62E2DC44AF3030971E174FB32EAA379D@hasmsx107.ger.corp.intel.com> Date: Tue, 5 Apr 2016 16:25:09 +0300 Message-ID: (sfid-20160405_152517_195140_8200E260) Subject: Re: iwlwifi monitor mode: No data frame captured on 5 Ghz From: Gucea Doru To: "Grumbach, Emmanuel" Cc: "linux-wireless@vger.kernel.org" , "Gucea, Doru" Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, Apr 5, 2016 at 1:00 PM, Grumbach, Emmanuel wrote: >> >> Hello, >> >> I am trying to capture packets that are exchanged between an AP and a >> smartphone on the 5Ghz frequency. For generating traffic, I upload UDP >> traffic from a laptop PC towards the smartphone using iperf. >> >> The problem is that I can see _only_ the control frames like RTS/CTS, Block >> ACK, while the data packets are not captured. I uploaded the Wireshark >> capture files at [1] (located inside the folders whose name starts with 5Ghz). > > Most likely the packets on A band have a VHT preamble and your SKU is 11N only. My card, Intel 7260 [1] supports 802.11 ac. So it should also support VHT, right? Is there any interface in user-space for checking after VHT? However, I noticed a "failure" message in dmesg: [ 4.030428] Intel(R) Wireless WiFi driver for Linux, in-tree: [ 4.030570] iwlwifi 0000:04:00.0: irq 37 for MSI/MSI-X [ 4.030760] iwlwifi 0000:04:00.0: Direct firmware load for iwlwifi-7260-10.ucode failed with error -2 [ 4.035509] iwlwifi 0000:04:00.0: loaded firmware version 25.228.9.0 op_mode iwlmvm [ 4.454772] iwlwifi 0000:04:00.0: Detected Intel(R) Dual Band Wireless N 7260, REV=0x144 [ 4.454825] iwlwifi 0000:04:00.0: L1 Disabled - LTR Enabled [ 4.455055] iwlwifi 0000:04:00.0: L1 Disabled - LTR Enabled [ 15.049933] iwlwifi 0000:04:00.0: L1 Disabled - LTR Enabled [ 15.050269] iwlwifi 0000:04:00.0: L1 Disabled - LTR Enabled Also, the maximum bit rate reported by iwconfig is 150 Mb/s, so my assumption is that the card can't enter into the 802.11 ac mode, it just stays into 802.11n. doru@doru-N551JK:~$ iwconfig wlan0 wlan0 IEEE 802.11abgn ESSID:"5_mptcp" Mode:Managed Frequency:5.24 GHz Access Point: C4:6E:1F:4B:10:A2 Bit Rate=150 Mb/s Tx-Power=22 dBm Retry short limit:7 RTS thr:off Fragment thr:off Power Management:on Link Quality=70/70 Signal level=-36 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:0 Invalid misc:22 Missed beacon:0 [1] http://www.intel.com/content/www/us/en/wireless-products/dual-band-wireless-ac-7260-bluetooth-brief.html > Another option is that the traffic uses LDPC encoding and this device doesn't support it. > > >> >> If I use the 2.4 frequency, all the frames are captured. I also uploaded the >> Wireshark packet traces for 2.4Ghz at [1] (located inside the folders whose >> name starts with 2.4 Ghz). >> >> Is this a known bug or am I doing something wrong? >> >> Additional details: >> Wi-Fi card: iwlwifi 0000:04:00.0: Detected Intel(R) Dual Band Wireless N 7260, >> REV=0x144 Firmware version: iwlwifi 0000:04:00.0: loaded firmware version >> 25.228.9.0 op_mode iwlmvm >> Traffic encryption: WPA & WPA2 Personal >> Setting up the card in wireless mode: >> ip link set dev wlan0 down >> iw wlan0 set type monitor >> ip link set dev wlan0 up >> iw wlan0 set freq 5240 >> >> [1] https://drive.google.com/open?id=0B5SBH08PU_Chek9rOHY0VkxFRUE >> >> Thank you, Doru