Controller-less WLANs

Q:

What is the maximum number of BSSIDs that can be monitored by an Aruba AP? 
 

An Aruba AP (both Instant and AOS), can monitor the the presence of other BSSIDs and SSIDs in its environment. We can check the list of monitored BSSIDs in the output of, 

#show ap monitor ap-list                            (FOR INSTANT APs) 
#show ap monitor ap-list ap-name <AP-NAME>          (FOR AOS APs)

Example: 

Rajaguru-115-IAP-1# show ap monitor ap-list 

Monitored AP Table
------------------
bssid              essid                   chan  ap-type      phy-type        dos      dt/mt            ut/it    encr            nstas  avg-snr  curr-snr  avg-rssi  curr-rssi  wmacs  ibss  cl-delay  
-----              -----                   ----  -------      --------        ---      -----            -----    ----            -----  -------  --------  --------  ---------  -----  ----  --------  
18:64:72:af:3d:34  Mac-Auth                44    valid        80211a-HT-20    disable  5428171/4353731  0/0      open            0      66       65        28        30         0      no    0         
18:64:72:af:3d:35  Dot1x-Auth              44    valid        80211a-HT-20    disable  5427794/4352722  0/0      wpa2-8021x-aes  0      67       65        27        30         0      no    0         
18:64:72:bc:32:04  Mac-Auth                1     valid        80211b/g-HT-20  disable  929551/929544    0/0      open            0      45       45        50        50         0      no    0         
18:64:72:bc:32:05  Dot1x-Auth              1     valid        80211b/g-HT-20  disable  929551/929548    0/0      wpa2-8021x-aes  0      45       45        50        50         0      no    0         
ac:a3:1e:66:ec:f0  Aruba-8.0-psk           11    interfering  80211b/g-HT-20  disable  315829/54875     35/5     wpa2-psk-aes    0      0        69        0         26         0      no    0         
18:64:72:c1:c1:e2  instant                 1     interfering  80211b/g-HT-20  disable  203951/100846    0/0      open            0      63       63        31        32         0      no    0         
44:48:c1:58:a3:01  chnocp1                 6     interfering  80211b/g-HT-20  disable  85402/53896      15/2     wpa2-psk-aes    0      0        48        0         47         0      no    0         
94:b4:0f:5a:60:00  test1                   11    interfering  80211b/g-HT-20  disable  56297/29698      121/0    open            0      0        56        0         39         0      no    0         
18:64:72:cc:b8:23  Test4                   1     interfering  80211b/g-HT-20  disable  44905/21624      0/0      wpa2-psk-aes    0      51       39        43        56         0      no    0         
<<<<<TRUNCATED>>>>>
18:64:72:f9:cd:40  instant                 6     interfering  80211b/g-HT-20  disable  44546/17220      51/0     open            0      0        59        0         36         0      no    0         
40:e3:d6:43:fc:20  SetMeUp-CC:3F:C2        11    interfering  80211b/g-HT-20  disable  42688/18911      141/0    open            0      0        61        0         34         0      no    0         
94:b4:0f:5a:7b:63  ssid_5                  1     interfering  80211b/g-HT-20  disable  18149/7866       231/230  open            0      0        46        0         49         0      no    0         
94:b4:0f:5a:5c:c0  IAP-wireless-client     11    interfering  80211b/g-HT-20  disable  17485/8262       180/5    open            0      0        60        0         35         0      no    0         
94:b4:0f:5a:7b:66  ssid_8                  1     interfering  80211b/g-HT-20  disable  304/304          231/230  open            0      0        46        0         49         0      no    0         
94:b4:0f:5a:7b:67  ssid_9                  1     interfering  80211b/g-HT-20  disable  259/259          231/230  open            0      0        45        0         50         0      no    0         
94:b4:0f:5a:7b:68  ssid_10                 1     interfering  80211b/g-HT-20  disable  259/259          231/230  open            0      0        46        0         49         0      no    0         
Start:0
Length:250
Total:250
Rajaguru-115-IAP-1#

The APs can save upto 256 BSSIDs in the monitored AP list. 

In some testing or lab environments, where a lot of APs broadcasting multiple BSSIDs are used, there can be more than 256 BSSIDs. In such cases, the monitored list can display only 256 entries that were first seen by the AP. When the monitor list is full, new entry cannot be saved until the old entry ages out.