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Access network design for branch, remote, outdoor, and campus locations with HPE Aruba Networking access points and mobility controllers.
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Removing channel 1 from 2.4?

This thread has been viewed 3 times
  • 1.  Removing channel 1 from 2.4?

    Posted Jan 14, 2014 12:56 PM

    We are having an issue with one of our residence buildings (16 floors, old hotel converted) that we are seeing a lot of access points from a condo building next door with way too many DSL routesr all on channel 1.  Our channel busy is very 'busy' on channel 1 so we are considering removing channel 1 and just keeping channels 6 and 11 to improve performance.

     

    About 45% of our clients are on 2.4ghz and 55% are on 5ghz, and this building has 162 APs (all AP65s so no 802.11n).

     

    Has anyone else had a situation like this?  If so what did you do to mitigate the situation?



  • 2.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 01:02 PM

     

    That could potentially create more issues since the APs only have 2 channels to work with , how far are those other APs ?

     

    What's the current min/max power levels under ARM for .11g



  • 3.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 01:12 PM

    The other APs are across the street in a high rise, see attached street view, building on the right is our building, building on the left is the condo.

     

    The power levels are set Min 9, Max 15

     

    https://maps.google.ca/maps?ll=45.510572,-73.575976&spn=0.011759,0.014484&t=m&z=16&layer=c&cbll=45.510616,-73.576091&panoid=oZdF15EaTEEMIW9pBD_hOw&cbp=12,312.29,,0,-13.6



  • 4.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 01:29 PM

    Here are the neighbors on one of my worst APs, it has a channel busy of 80%, you can see a lot of neighbors on channel 1

     

     

    ARM Neighbors
    -------------
    bssid              essid                            channel  rssi  tx-power  PL (dB)  AP Flags  Last Update (Total updates)
    -----              -----                            -------  ----  --------  -------  --------  ---------------------------
    00:0b:86:4a:92:60  rez.mcgill.ca                    11       20    12        89       Active    2014-01-14 13:19:14(705)
    00:0b:86:4a:e4:20  rez.mcgill.ca                    1        19    12        90       Active    2014-01-14 13:24:48(1257)
    00:0b:86:4a:95:00  rez.mcgill.ca                    1        20    9         81       Active    2014-01-14 12:45:29(430)
    d8:6c:e9:2b:b9:c1  BELL-249                         1        11    0         0        Passive
    c4:09:38:01:12:0b  CIK0792                          1        12    0         0        Passive
    00:0b:86:4a:95:01  wpa.rez.mcgill.ca                1        22    9         0        Passive
    b8:c7:5d:0a:80:9d  RVZ                              1        21    0         0        Passive
    2c:e4:12:a2:d7:1f  BELL181                          1        14    0         0        Passive
    00:0b:86:4a:8b:81  wpa.rez.mcgill.ca                1        9     12        97       Passive
    2c:e4:12:94:bf:ed  fenur                            1        13    0         0        Passive
    2c:e4:12:8b:37:37  BELL699                          1        13    0         0        Passive
    4c:17:eb:db:c4:d3  Avish                            1        14    0         0        Passive
    68:15:90:3e:66:62  BELL536                          1        12    0         0        Passive
    00:0b:86:4a:8b:80  rez.mcgill.ca                    1        10    12        99       Passive
    2c:e4:12:8d:82:47  BELL108                          1        14    0         0        Passive
    00:01:8e:f3:92:d9  logitec2nd71                     1        6     0         0        Passive
    2c:44:fd:d1:c4:10  HP-Print-10-Deskjet 3510 series  1        4     0         0        Passive
    d8:6c:e9:28:23:dd  BELL637                          1        6     0         0        Passive
    d8:6c:e9:12:65:1f  BELL988                          1        9     0         0        Passive
    34:ef:44:fb:92:a9  BELL832                          1        3     0         0        Passive
    00:01:8e:f3:92:d8  logitec71                        1        1     0         0        Passive
    2c:e4:12:98:a0:eb  BELL205                          2        12    0         0        Passive
    2c:e4:12:8c:00:cf  BELL366                          1        3     0         0        Passive
    2c:e4:12:94:fa:ed  BELL630                          1        22    0         0        Passive
    2c:e4:12:82:b4:35  BELL846                          1        16    0         0        Passive
    2c:e4:12:a8:e1:1d  BELL703                          1        6     0         0        Passive
    d8:6c:e9:18:3a:d1  BELL682                          1        4     0         0        Passive
    2c:e4:12:8f:1a:7d  BELL428                          1        5     0         0        Passive
    d8:6c:e9:0f:32:d2  Byron                            1        6     0         0        Passive
    00:0b:86:4a:cb:e0                                   11       0     9         85       Active    2014-01-14 13:18:08(13)
    d8:6c:e9:29:8e:d5  BELL781                          1        6     0         0        Passive
    00:0b:86:4a:70:40  rez.mcgill.ca                    1        11    12        97       Active    2014-01-14 12:54:34(6)
    58:6d:8f:e0:67:5f  Max's              1        6     0         0        Passive
    00:0b:86:4a:70:60                     6        0     9         77       Active    2014-01-14 13:25:12(14)
    5e:96:9d:69:46:a6  AMNETGuest         1        2     0         0        Passive
    00:0b:86:4a:8f:60  rez.mcgill.ca      1        5     15        110      Passive
    20:c9:d0:a0:59:da  AbdulAziz          1        5     0         0        Passive
    00:0b:86:4a:e4:21  wpa.rez.mcgill.ca  1        19    0         0        Passive
    2c:e4:12:8d:4a:c7  BELL860            1        4     0         0        Passive
    00:0b:86:4b:0f:a0  rez.mcgill.ca      1        6     15        102      Passive
    00:0b:86:4b:0f:a1  wpa.rez.mcgill.ca  1        6     15        101      Passive
    00:0b:86:4b:1e:80                     11       0     15        95       Active    2014-01-14 13:22:56(1)


  • 5.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 02:26 PM

    I would manipulate the ARM threshold settings and still allow for automatic channel selection.  I agree that removing channel 1 completely would cause more harm than good.

     

     



  • 6.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 02:32 PM

    @Evan W wrote:

    I would manipulate the ARM threshold settings and still allow for automatic channel selection.  I agree that removing channel 1 completely would cause more harm than good.


    We do have automatic channel selection for 1, 6 and 11.  Not sure how much more we can tweak, the fact is there is just too much noise on channel 1 in this environment due to outside sources out of our control, hence our idea just to not use this channel and use 6 and 11, and maybe even then lower power levels from 6->12 instead of 9->15



  • 7.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 02:34 PM

    Why do you think that ARM is not moving the APs off of channel 1 on it's own?  



  • 8.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 02:36 PM

    It doesn't look like it is:

     

     

    ARM History
    -----------
    Time of Change       Old Channel  New Channel  Old Power  New Power  Reason
    --------------       -----------  -----------  ---------  ---------  ------
    2014-01-14 13:59:44  1            1            12         9          P-
    2014-01-14 13:39:53  1            1            9          12         P+
    2014-01-14 13:28:05  1            1            12         9          P-
    2014-01-14 12:37:36  1            1            9          12         P+
    2014-01-14 12:20:43  1            1            12         9          P-
    2014-01-14 11:35:53  1            1            9          12         P+
    2014-01-14 10:54:31  1            1            15         9          P-
    2014-01-14 10:50:06  1            1            12         15         P+
    2014-01-14 10:44:47  1            1            9          12         P+
    2014-01-14 10:26:33  1            1            12         9          P-
    2014-01-14 10:20:22  1            1            9          12         P+
    2014-01-14 10:11:57  1            1            12         9          P-
    2014-01-14 10:03:49  1            1            9          12         P+
    2014-01-14 09:56:41  1            1            12         9          P-
    2014-01-14 08:43:43  1            1            9          12         P+
    2014-01-14 08:37:32  1            1            12         9          P-
    2014-01-14 08:33:01  1            1            9          12         P+
    2014-01-14 08:26:00  1            1            12         9          P-
    2014-01-14 07:57:06  1            1            9          12         P+
    2014-01-14 07:36:10  1            1            12         9          P-
    2014-01-14 07:28:37  1            1            9          12         P+
    2014-01-14 07:10:57  1            1            12         9          P-
    2014-01-14 07:03:40  1            1            9          12         P+
    2014-01-14 06:23:58  1            1            12         9          P-
    2014-01-14 06:18:18  1            1            9          12         P+
    2014-01-14 06:11:08  1            1            12         9          P-
    2014-01-14 05:55:04  1            1            9          12         P+
    2014-01-14 05:42:32  1            1            12         9          P-
    2014-01-14 05:24:43  1            1            9          12         P+
    2014-01-14 05:19:59  1            1            12         9          P-
    2014-01-14 05:14:49  1            1            9          12         P+
    2014-01-14 05:08:45  1            1            12         9          P-


  • 9.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 02:49 PM

     

    Run the following command  , it will tell you how many devices are currently interfering with your AP or APs:

     

    show ap monitor ap-list ap-name <ap-name>

     

    Monitored AP Table
    ------------------
    bssid essid chan ap-type phy-type dos dt/mt ut/it encr nstas avg-rssi curr-rssi wmacs ibss

    ----- ----- ---- ------- -------- --- ----- ----- ---- ----- -------- --------- ----- ----

     

    Under the AP-TYPE column you can see whether there's devices interfering with your AP

     

    Based on the ARM history output it doesn't seem as your AP is trying to change channels constently because of interference 

     

    You could also run this command to make sure there's isn't a low noise levels 

    show ap arm rf-summary ap-name <apname>

     

     



  • 10.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 02:51 PM

    @victorfabian wrote:

     

    Run the following command  , it will tell you how many devices are currently interfering with your AP or APs:

     

    show ap monitor ap-list ap-name <ap-name>

     

    Monitored AP Table
    ------------------
    bssid essid chan ap-type phy-type dos dt/mt ut/it encr nstas avg-rssi curr-rssi wmacs ibss

    ----- ----- ---- ------- -------- --- ----- ----- ---- ----- -------- --------- ----- ----

     

    Under the AP-TYPE column you can see whether there's devices interfering with your AP


     

    wirelessrez-local71-wmc) # show ap monitor ap-list ap-name newrez-11-ap68 channel 1
    
    Tue Jan 14 14:50:30 2014
    
    
    
    Monitored AP Table
    ------------------
    bssid              essid                            chan  ap-type               phy-type        dos      dt/mt            ut/it    encr            nstas  avg-rssi  curr-rssi  wmacs  ibss
    -----              -----                            ----  -------               --------        ---      -----            -----    ----            -----  --------  ---------  -----  ----
    00:0b:86:46:70:20  rez.mcgill.ca                    1     valid                 80211b/g        disable  2840465/2840465  0/0      open            0      20        20         0      no
    00:0b:86:46:70:21  wpa.rez.mcgill.ca                1     valid                 80211b/g        disable  2840465/2840465  0/0      wpa2-8021x-aes  4      20        20         128    no
    00:0b:86:4a:92:60  rez.mcgill.ca                    1     valid                 80211b/g        disable  699286/663723    0/0      open            0      19        19         0      no
    00:0b:86:4a:e4:20  rez.mcgill.ca                    1     valid                 80211b/g        disable  193244/176923    204/203  open            0      0         19         0      no
    c4:09:38:01:12:0b  CIK0792                          1     interfering           80211b/g-HT-20  disable  34081/34081      3/2      wpa-psk-tkip    1      11        13         1      no
    b8:c7:5d:0a:80:9d  RVZ                              1     interfering           80211b/g-HT-20  disable  34081/34081      0/0      wpa2-psk-aes    2      20        22         4      no
    2c:e4:12:a2:d7:1f  BELL181                          1     interfering           80211b/g        disable  34081/34081      0/0      wpa2-psk-aes    1      14        15         2      no
    00:0b:86:4a:8b:81  wpa.rez.mcgill.ca                1     valid                 80211b/g        disable  34081/34081      15/14    wpa2-8021x-aes  1      9         7          28     no
    2c:e4:12:94:bf:ed  fenur                            1     suspected-rogue(20%)  80211b/g-HT-20  disable  34081/34081      0/1      wpa2-psk-aes    0      12        13         0      no
    2c:e4:12:8b:37:37  BELL699                          1     interfering           80211b/g-HT-20  disable  34080/34080      0/0      wpa2-psk-aes    0      11        13         3      no
    4c:17:eb:db:c4:d3  Avish                            1     interfering           80211b/g-HT-20  disable  34078/34078      0/0      wpa2-psk-aes    2      11        11         1      no
    68:15:90:3e:66:62  BELL536                          1     interfering           80211b/g-HT-20  disable  34078/34078      1/0      wpa2-psk-aes    0      9         11         0      no
    00:0b:86:4a:8b:80  rez.mcgill.ca                    1     valid                 80211b/g        disable  34077/34077      6/5      open            0      8         6          0      no
    2c:e4:12:8d:82:47  BELL108                          1     interfering           80211b/g-HT-20  disable  34076/34076      0/0      wpa2-psk-aes    0      12        12         3      no
    00:01:8e:f3:92:d9  logitec2nd71                     1     interfering           80211b/g        disable  34075/34075      26/25    wep             0      3         4          1      no
    2c:44:fd:d1:c4:10  HP-Print-10-Deskjet 3510 series  1     interfering           80211b/g-HT-20  disable  34072/34072      24/23    wpa2-psk-aes    0      6         9          0      no
    d8:6c:e9:28:23:dd  BELL637                          1     interfering           80211b/g-HT-20  disable  34070/34070      3/2      wpa2-psk-aes    0      5         6          1      no
    d8:6c:e9:12:65:1f  BELL988                          1     interfering           80211b/g-HT-20  disable  34068/34068      0/0      wpa2-psk-aes    1      9         13         1      no
    34:ef:44:fb:92:a9  BELL832                          1     interfering           80211b/g        disable  34063/34063      80/79    wep             0      0         4          0      no
    00:01:8e:f3:92:d8  logitec71                        1     interfering           80211b/g-HT-20  disable  34061/34061      29/28    wpa-psk-tkip    0      3         4          0      no
    2c:e4:12:94:fa:ed  BELL630                          1     interfering           80211b/g-HT-20  disable  32462/32462      0/0      wpa2-psk-aes    0      20        22         0      no
    2c:e4:12:82:b4:35  BELL846                          1     interfering           80211b/g-HT-20  disable  23825/23825      1/0      wpa2-psk-aes    0      14        15         0      no
    00:0b:86:4a:e4:21  wpa.rez.mcgill.ca                1     valid                 80211b/g        disable  5632/5632        539/538  wpa2-8021x-aes  0      0         19         7      no
    2c:e4:12:8e:57:5d  BELL359                          1     interfering           80211b/g-HT-20  disable  3937/3937        8/7      wpa2-psk-aes    0      6         7          1      no
    00:0b:86:4b:1d:c1  wpa.rez.mcgill.ca                1     valid                 80211b/g        disable  2657/2657        0/0      wpa2-8021x-aes  0      11        11         0      no
    00:0b:86:4b:1d:c0  rez.mcgill.ca                    1     valid                 80211b/g        disable  2656/2656        0/0      open            0      11        12         0      no
    d8:6c:e9:0f:32:d2  Byron                            1     interfering           80211b/g-HT-20  disable  2334/2334        200/6    wpa2-psk-aes    1      0         4          0      no
    2c:e4:12:8f:1a:7d  BELL428                          1     interfering           80211b/g-HT-20  disable  2099/2099        4/3      wpa2-psk-aes    0      2         4          0      no
    00:0b:86:4c:40:a0  rez.mcgill.ca                    1     valid                 80211b/g        disable  1621/1621        0/0      open            0      9         10         0      no
    00:0b:86:4c:40:a1  wpa.rez.mcgill.ca                1     valid                 80211b/g        disable  1618/1618        1/0      wpa2-8021x-aes  0      11        13         0      no
    58:6d:8f:e0:67:5f  Max's                            1     interfering           80211b/g-HT-20  disable  1463/1463        4/3      wpa-psk-tkip    0      4         5          0      no
    00:0b:86:4a:92:61  wpa.rez.mcgill.ca                1     valid                 80211b/g        disable  1355/1355        0/0      wpa2-8021x-aes  3      20        19         31     no
    00:0b:86:4c:3f:20  rez.mcgill.ca                    1     valid                 80211b/g        disable  925/925          1/0      open            0      10        12         0      no
    00:0b:86:4c:3f:21  wpa.rez.mcgill.ca                1     valid                 80211b/g        disable  915/915          0/0      wpa2-8021x-aes  0      11        11         0      no
    2c:e4:12:a8:e1:1d  BELL703                          1     interfering           80211b/g-HT-20  disable  724/724          29/28    wpa2-psk-aes    0      3         3          0      no
    5e:96:9d:69:46:a6  AMNETGuest                       1     interfering           80211b/g-HT-20  disable  516/516          81/80    wpa-psk-tkip    0      0         4          0      no
    58:6d:8f:70:85:d6  Tourelles1                       1     interfering           80211b/g-HT-20  disable  506/506          224/223  wpa-psk-tkip    0      0         1          1      no
    5c:96:9d:69:46:a5  AMNet                            1     suspected-rogue(60%)  80211b/g-HT-20  disable  500/500          28/27    wpa2-psk-aes    0      4         4          0      no
    d8:6c:e9:29:8e:d5  BELL781                          1     interfering           80211b/g-HT-20  disable  420/420          282/281  wpa2-psk-aes    0      0         4          0      no
    2c:e4:12:8c:00:cf  BELL366                          1     interfering           80211b/g-HT-20  disable  393/393          27/16    wpa2-psk-aes    1      2         2          0      no
    20:c9:d0:a0:59:da  AbdulAziz                        1     interfering           80211b/g-HT-20  disable  63/63            29/28    wpa2-psk-aes    0      5         6          0      no
    00:0b:86:4a:8f:60  rez.mcgill.ca                    1     valid                 80211b/g        disable  15/15            15/15    open            0      3         3          0      no
    Start:0
    Length:42
    Total:42

    That is just one AP, I am in the process of getting stats on all my APs to see channels and power levels.



  • 11.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 02:56 PM

    My stats I have found for this building with 162 APs:

     

    Channel 1: 60 APs

    Channel 6: 31 APs

    Channel 11: 71 APs

     

    Power Levels:

    9: 61

    12: 36

    15: 65



  • 12.  RE: Removing channel 1 from 2.4?

    EMPLOYEE
    Posted Jan 14, 2014 03:09 PM

    @mzac wrote:

    My stats I have found for this building with 162 APs:

     

    Channel 1: 60 APs

    Channel 6: 31 APs

    Channel 11: 71 APs

     

    Power Levels:

    9: 61

    12: 36

    15: 65


    Questions:

     

    Do you have those access points mounted in the halls or in rooms?

    How many per floor?

    What is the square footage of each floor?

     



  • 13.  RE: Removing channel 1 from 2.4?

    Posted Jan 14, 2014 03:23 PM

    @cjoseph wrote:

    @mzac wrote:

    My stats I have found for this building with 162 APs:

     

    Channel 1: 60 APs

    Channel 6: 31 APs

    Channel 11: 71 APs

     

    Power Levels:

    9: 61

    12: 36

    15: 65


    Questions:

     

    Do you have those access points mounted in the halls or in rooms?

    How many per floor?

    What is the square footage of each floor?

     


    Each floor is about 25,000 sq ft in with 162 APs so each AP covers about 154 sq feet and we cover 16 floors.  They are mounted in the rooms near the door. There are approx 12 APs per floor.



  • 14.  RE: Removing channel 1 from 2.4?
    Best Answer

    EMPLOYEE
    Posted Jan 14, 2014 03:31 PM

    Okay.

     

    If you have 1/3 of your access points at 9, theoretically it means that it has them on the lowest power to avoid interference.  It probably would go to 3 if you let it, but that is too low.  You could turn all access points that are at 9 on one floor to Air monitors and see if that helps your utilization. [EDIT-Turn the g radio on all of those access points to air monitors]

     

    I see that you have other access points that you see as neighbors, but they are only really significant at a certain signal strength.  If those access points are at 15 RSSI or lower, they are much less of an issue than those that are at say 20 and above.  I do not have a 3-d model of your deployment, but if you can afford to put the access points that turn themselves down into an ap-group for air monitors, we will be able to see if that helps your issue.  In addition, make sure that you do not have any unnecessary Virtual APs enabled, because each added Virtual AP that is not in use increases the utilization.  Please see the excellent article here:  http://www.revolutionwifi.net/2013/10/ssid-overhead-how-many-wi-fi-ssids-are.html

     



  • 15.  RE: Removing channel 1 from 2.4?

    Posted Jan 15, 2014 09:24 AM

    @cjoseph wrote:

    Okay.

     

    If you have 1/3 of your access points at 9, theoretically it means that it has them on the lowest power to avoid interference.  It probably would go to 3 if you let it, but that is too low.  You could turn all access points that are at 9 on one floor to Air monitors and see if that helps your utilization. [EDIT-Turn the g radio on all of those access points to air monitors]

     

    I see that you have other access points that you see as neighbors, but they are only really significant at a certain signal strength.  If those access points are at 15 RSSI or lower, they are much less of an issue than those that are at say 20 and above.  I do not have a 3-d model of your deployment, but if you can afford to put the access points that turn themselves down into an ap-group for air monitors, we will be able to see if that helps your issue.  In addition, make sure that you do not have any unnecessary Virtual APs enabled, because each added Virtual AP that is not in use increases the utilization.  Please see the excellent article here:  http://www.revolutionwifi.net/2013/10/ssid-overhead-how-many-wi-fi-ssids-are.html

     


    So if I read between the lines you're basically saying I should be turning on mode aware?



  • 16.  RE: Removing channel 1 from 2.4?

    EMPLOYEE
    Posted Jan 14, 2014 02:44 PM
    How is your coverage? If ARM can afford to go all the way down to 9, you might want to turn off an access point here and there and measure your utilization after that.


  • 17.  RE: Removing channel 1 from 2.4?

    EMPLOYEE
    Posted Jan 15, 2014 09:27 AM
    I would say no, because we want to selectively turn off access points in an area. Mode aware is not deterministic enough for this exercise.