NOTE:A spectrum monitor or hybrid AP automaticall ydi sconnectsfrom a client when you close the browser window youused to
connectthe spectrum monitor to your client. However, if you are using Internet Explorer and have multiple instances of an
InternetExplorer browser open, the data-streaming connection to the spectrum monitor or hybrid AP is not released until 60
secondsafter you close the spectrum client browser window. During this 60-second period, the spectrum monitor is still
connectedto the client.
Whena spect rummonito r or hybrid AP is not subscribed to any client, it still performs all classification tasks and
collect allnecessary channel lists and device i nformation.You can view classification, device and channel information
for any active spectrum monitor or hybrid AP via the controller's command-lineinterface, regardless of whether or
not that device is sending real-time spectrum data to another client WebUI.
Individual spectrumanalysis graphs and charts are explained in detail in "Customizing Spectrum Analysis Graphs" on
page 582.

Hybrid AP C hannel Cha nges

By default,a hybrid AP only monitors the channel specified in it s 802.11a or 802 .11g radio profile for spectrum
interference.If you want to change the channel monitored by a hybrid AP, you must edi t the channels etting in
those profiles. Thereare, however, other ArubaOS features that may automatically change the channels on hybrid
APs. APs using Dynamic FrequencySelection (D FS) performoff-channel scanning to detect the presence of satellite
and radartransmissions, and swi tch to a different channeli f it detects that satellite o r radartransmissions are
present.AP s using the Adaptive Radio Response (ARM) feature constantly monitor the network and automatically
select the best channel and transmission power settings for that AP. I f you manuallychange a channel monitored by
a hybrid AP, best practices are to temporarily disable the ARM feature, as ARM may automatically return the
channelto its previous setting.
If a hybrid AP is using ARM or DFS, that hybrid AP may automati callymove t o a differentchannel in response to
changesi nt henetwork environment. If a hybrid AP changes channelswhile it i s connected to a spectrumanalysis
client, the hybridAP updates the graphs in the spectrumdashboard to start displaying spectrum data for the new
channel,and sends a log message to the session log. For details on changingt hechannel monitored by a hybrid AP,
see "802.11aand 802.11g RFManagemen t Profiles" on page 424.

Hybrid APs Usin g Mode-Awa re ARM

If a radioi sco nfiguredas a hybrid AP and thatA P is enabledwith mode-aware ARM, the hybridAP can change to
an Air Monitor (or

AM

) if too many APs are detected in the area. If the ARM feature changesa hybrid AP to an Air
Monitor, that AM does not provide spectrum data after the mode change. The AM unsubscribesfrom any connected
spectrumanalysis client, send a log message warning about the change.I fmo de-awareARM changes the AM back to
an AP, the hybrid AP does not automatically resubscribe back to the spectrum analysis client. The hybrid AP must
manuallyresubscribed before it can appear in the client’s spectrum monitor s page.
Creating Spectrum Mo nitors and Hybrid APs
Each controllercan support up to 22 active WebUI connections to spectrum monitor or hybridA P radios.I fyo u
planon usi ngspect rummonito rs or hybrid APs as a permanent overlay to constantly monitor yo urnetwo rk,you
shouldcreate a separate AP group for these devices. If you plan on temporarily converting campus APs t o spectrum
monitors, best practices areto use the spectrum local override profileto convert an AP to a spectrum monitor.
This section describes the followingtasks for converting regular APs into hybrid APs or spectrum monitors.
l"ConvertingA Ps to Hybrid APs " on page5 75
l"Convertingan I ndividualA P to a Spectrum Monitor" on page 575
l"Convertinga Group of A Ps to Spectrum Monitors" on page 576
DellPowerConnect W- Series ArubaOS 6.2 | UserGuide SpectrumAnalysis | 574