SmartSelect vs specific channel for 7982

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Hi. I have the Ruckus 7982 set with SmartSelect for the channel. I notice that it uses channels that are not necessarily the recommended 1,6,11. For example, at this very moment, its using channel 3. My office is in a building with many other wireless networks all using either 1,6 or 11. Is it still a good practice to still set to SmartSelect? Or should i override and specify either 1,6 or 11?

Also, I have a separate netgear access point that i just have one as a separate SSID which i've been using as a backup since i was still evaluating the Ruckus access point. Is it a better practice going forward to sync the SSID name to be the same?

thanks
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Edward Chin

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Posted 3 years ago

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Munish Dhiman, Employee

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Hi Edward,

The Smart Select feature will always attempt to use the best channel available.
If you manually select a channel, Smart Select will be unable to automatically switch
channels to adjust to changes in the environment.

You would need to identify the signal strength of the access point , If you are getting strong signal on all the 3 non-overlapping channel, the you should definitely use Smart select .Because interference will degrade you wireless performance.

You can keep the SSID same on netgear AP , however i doubt about the roaming between these two . I would suggest to stick to one vendor.

Thanks
Munish
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John D, AlphaDog

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SmartSelect will ALWAYS pick better channel assignments than a static channel assignment. It basically works by trying every single channel constantly and remembering the max throughput on each channel. Then it stays on the channel that it knows has the best capacity.

So, if you only have 3 AP's with heavy traffic, they will all stick on 1,6,11. But in reality, one of those channels will likely be noisy due to either non-802.11 sources of 2.4GHz interference or someone operating another 2.4GHz access point. So the conventionally "recommended" 1, 6, 11 might be a bad choice. In fact, if you are deploying in a rogue environment where everyone else chooses 1, 6, 11, then those might be the WORST channels. The overlapped channels might actually have more capacity than 1,6,11.

The main downside with SmartSelect is that it can take a few hours for it to stabilize because it is essentially exhaustively trying every channel to establish how much capacity it has. Not all clients support the 802.11h channel change announcements (CSA) that Ruckus sends. Those clients may be dropped off the network every time a channel switch happens. If this is an issue in your environment, there are two solutions:

(1) Use the CLI to change the channel fly MTBC (Mean Time Between Change) to something higher than the default 100 minutes. This can reduce the amount of disruption.
(2) Use ChannelFly for a few hours to establish the best channels, then manually set those channels. If you have a ZoneDirector, it can automate this process by you selecting the "Stop Channelfly after ___ minutes" option. If you're standalone, you should run ChannelFly for a day, then log into the Web UI and see which channels the AP has picked for 2.4 and 5GHz, then manually set those channels.

The downside of approach (2) is that you cannot dynamically react to changes in capacity. So if someone happens to bring in a rogue AP that uses the exact same channel you are using, you'll have to manually diagnose that capacity loss if it becomes an issue.

For your second question, I think the answer depends on your goals. Are you still evaluating, or are you now using the Netgear AP to add more wifi coverage in addition to the Ruckus AP's? In a standalone environment roaming is done purely on the client side, so the client won't know what's a Ruckus and what's a Netgear. But having a mixed environment like this will make it much harder for you to diagnose what is wrong if someone complains about wifi performance/connectivity.
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Michael Brado, Official Rep

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Did You Know:

If you have a Standalone AP, your AP radios (2.4G and/or 5G) are only enabled
when you have defined/activated an SSID on them, individually and independently.

SmartSelect or a static channel, are the only options (no Channelfly w/o ZD).

A standalone AP will not change channels by itself. The SmartSelect algorithm
will evaluate SSIDs seen and interference on the available channels, and pick
the best one - when the AP is first powered on, or rebooted (only).
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Primož Marinšek, AlphaDog

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I think it's the other way around. It's either static channel or ChannelFly but not BG.
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John D, AlphaDog

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I remember being able to turn on BG scanning on standalone 9.8.0 with the CLI before. I don't exactly remember the command.
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Monnat Systems, AlphaDog

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I noticed that use of channelfly in smart select with standalone AP starting 9.3 version and even today some of the AP's which i have running 9.3 + so i think erred somewhere or something changed somewhere which went un-noticed..
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Michael Brado, Official Rep

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Yes, standalone AP SmartSelect has been using ChannelFly behavior. However, 7731 PtP bridges, which look like a standalone AP, appear to not follow this, and I've filed an ER with engineering to address the 7731 behavior.
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John D, AlphaDog

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Thanks Michael for confirming this!
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Michael Brado, Official Rep

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If using standalone APs, you can define the same SSID on a 3rd party AP, that
needs to be configured with the same encryption/cipher methods. Whether you
roam between two standalone Ruckus APs, or to the 3rd party one, your client
is going to do a full re-association/re-authentication, new each time. Ruckus APs
will likely provide better coverage, naturally, so you might not connect to the 3rd
party AP unless you are near to it.

If you employed a ZoneDirector/RuckOS controller, you would roam seamlessly
and faster between the Ruckus APs in your environment, and would want to
avoid having a 3rd party AP using the same SSID.
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Edward Chin

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I have the access point set up as stand-alone with 9.8.1.0.101. Using an external tool, i never see the channel ever changing.. its been on ch. 3 since the start up 54 days ago.

Should I reboot it on a daily basis as a work around?
Is there a newer firmware version out there that implements the dynamic channel setting OR must i purchase a separate controller?
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Michael Brado, Official Rep

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You probably have clean air, with little noise or interference, and channel 3 may be the best 2.4G channel. With only one AP you won't likely see other SSIDs being advertised. You can reboot your AP and evaluate your chosen channels
once more. If they select the same ones again, those are likely your best choices.
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Bill Burns, AlphaDog

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If you want to exclude certain channels from consideration:
(like channels 2,3,4,5 and 7,8,9,10)

Assuming you're using a ZoneDirector:
Go to Configure / Access_Points / Access_Point_Groups and edit the "System Default" entry.
Under "Channel Range Settings": uncheck the undesired channels.

ChannelFly should now only be able to choose channels 1, 6 and 11. (on 2.4Ghz radios)

If you have excessive "interference detected" log messages on 5Ghz channels (and you suspect there is interference from non-ruckus APs) you can try the same trick there.

Beware, though:
If your interference is from other Ruckus APs (managed by the same controller) then eliminating the 5Ghz "problem" channels will only move the problem to another set of channels.

Re: ChannelFly in general:
If you're in a clean/"controlled" environment where you own+manage all the APs, you may not need it. (and a 1,6,11 strategy probably makes sense)

If you're in a noisy/congested environment where you do not control al the APs and interference comes from many distant APs (or non-WiFi devices) then ChannelFly and non-standard channels may be optimal for you.

(that's my opinion)