Controllerless Networks

Hi guys,

I have a IAP 105 network running 6.2.0.0-3.2.0.3_37632 Aruba OS and I found an strange behaviour: 

Many of my clients are showing too much retries in/out in the network. There aren´t noise nor interference problems. 

Could you help me?

Thanks,

Raúl

Hi Raul,

Check the switch ports that the AP's are connected to.  I saw a similar problem before and it was due to a speed/duplex mismatch between the AP and the switch port that it was connected to.

You should try going to the support tab and running the following commands on that particular AP and the output will give you a better understanding of your RF environment :

AP monitor ap table

AP arm history

AP arm rf summary

AP arm neighbors 

Hi,

Thank you, I checked the switch (it´s and old one) and I changed the port and also I tried to connect directly in the DSL router and the result was the same. I should try to change the physical mode from auto to 1000.

I´m going to run that commands and I will keep you posted,

Regards,

Raúl

Hi,

Here is the output of that ARM commands. I attached it as Office table.

Thanks in advance,

Raúl

Looks like this device (possibly a wireless printer near by) might be impacting your connection on channel 6 :

02:26:f6:90:2b:90  HPB110a.D5E55F  6        5

Hi,

I knew about that printer and I told my customer to deactivate the WiFi connection... but I can´t believe that this printer could be enough to be the reason of too many retries and connection problems. It should be just an interference problem... Nevertheless I´m going to ask again my customer to deactivate that printer

Regards,

Raúl

From the support tab try running the following:

AP Monitor AP Table

This command would allow to see which devices are interfering with your IAP

Monitored AP Table
------------------
bssid              essid            chan  ap-type      phy-type        dos      dt/mt          ut/it    encr          nstas  avg-rssi  curr-rssi  wmacs  ibss
-----              -----            ----  -------      --------        ---      -----          -----    ----          -----  --------  ---------  -----  ----
00:11:22:33:44:55  Linksys           6    interfering  80211b/g-HT-20  disable  543156/536048  0/0      wpa2-psk-aes  0      6         6          0      no

Hi,

I don´t see anything wrong...

Monitored AP Table

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

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

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

24:de:c6:bf:05:72  WLAN_1E43  6     valid    80211b/g-HT-20  disable  433308/141481  3/0    wpa-psk-tkip  1      34        34         5      no

24:de:c6:bf:07:1a  WLAN_1E43  44    valid    80211a-HT-40    disable  433308/433308  0/0    wpa-psk-tkip  1      40        40         16     no

24:de:c6:bf:07:12  WLAN_1E43  11    valid    80211b/g-HT-20  disable  433308/433308  0/0    wpa-psk-tkip  8      25        25         18     no

24:de:c6:bf:06:c2  WLAN_1E43  6     valid    80211b/g-HT-20  disable  433307/141548  3/0    wpa-psk-tkip  1      22        26         9      no

24:de:c6:bf:06:92  WLAN_1E43  6     valid    80211b/g-HT-20  disable  433298/33875   3/0    wpa-psk-tkip  1      22        23         4      no

24:de:c6:bf:02:a2  WLAN_1E43  11    valid    80211b/g-HT-20  disable  433281/304960  0/0    wpa-psk-tkip  34     30        30         18     no

24:de:c6:be:fa:d2  WLAN_1E43  11    valid    80211b/g-HT-20  disable  423247/320912  0/0    wpa-psk-tkip  10     9         9          18     no

24:de:c6:bf:05:7a  WLAN_1E43  60    valid    80211a-HT-40    disable  416715/11591   16/0   wpa-psk-tkip  1      23        23         7      no

24:de:c6:bf:06:ca  WLAN_1E43  100   valid    80211a-HT-40    disable  399178/11110   29/0   wpa-psk-tkip  4      13        13         5      no

24:de:c6:bf:06:9a  WLAN_1E43  100   valid    80211a-HT-40    disable  46209/1309     53/1   wpa-psk-tkip  0      0         12         2      no

Start:0

Length:10

Total:10

Any ideas?

Thanks in advance!

Is there any way that your clients can use WPA2-PSK-AES?  Full 802.11n speeds are not supported with WPA-PSK-TKIP

Hi,

That´s a good point. I´ll ensure all the clients are running WPA2-PSK-AES and also I will update this post if it works.

Thanks,

Raúl

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@Tejeda wrote:

Hi,

 

That´s a good point. I´ll ensure all the clients are running WPA2-PSK-AES and also I will update this post if it works.

 

Thanks,

Raúl

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Quite frankly, retries are a factor in congestion and are part of a functioning WLAN, so there is no magic number target.  One network with high density could have up to 50% of traffic be retries, and traffic can be bursty.  A good number is to have less than 30% sustained retries or find out when your clients are okay and measure that number.

If all the numbers are okay, but your clients are complaining, that is a good time to examine what you are doing.  If all of your clients are okay, get a snapshot of that environment to determine what is "normal".  If they are not okay, see how they have changed from the "normal".