Controllerless Networks

Just set up a 303H with latest firmware (6.5.4.5).  Single AP environment. If the band is set to ALL, the AP doesn't recognize any device as even having AC capability.  The devices are connecting to 2.4, even right next to the AP and getting a max throughput of about 45mbps.  If I limit the band to only 5GHz, then the devices connect properly and are identified as having AC capability.  I’ve tested with both IOS and Win 10 devices.

A fresh restart doesn’t help.  Rebooted all routers and switches.  

If I change Band steering mode to Prefer 5GHz, the devices connect to the 5GHz.  The problem with this is that they are connecting to 5GHz even when they are too far away and should be connecting to 2.4.  With the RAP109, latest firmware, and band steering Disabled, the device selected the correct frequency based on conditions.  And I am also able to get about 85Mbps with the RAP on 2.4.  

 

Update: After the AP-303H has been up for about 15 minutes, it seems to be working correctly.  Does it really take this long to fully boot everything?

Switching the band to 2.4 only and then reverting back to All, the condition is reset to only connecting on 2.4 

The access point needs to have seen probes from the client on the 5ghz band.  If it has not seen probes from the client on that band, it cannot steer clients.  If you had a high density environment, classification would happen more quickly.

Hi Colin.  Why doesn't the RAP109 exhibit this behavior?

If you think there is an issue, please open a TAC case. It could be a configuration issue or a bug. I cannot explain the difference with the limited information in your post.

In a single AP environment it will take longer for a client's capabilities to be discovered if it is not connecting on the 5ghz band. In that situation if the client never scans a 5ghz channel it will never be discovered. If it scans the 5ghz band and the access point is not on the same channel as the client (there are 23 channels) it will not be discovered. There is a greater chance that a client capabilities will be discovered in a dense AP environment.

Colin,

In another post regarding Band Steering, you wrote this:

"If you are using a 802.11ac AP, band steering is not used"

 

Is this still true?  It clearly makes a difference on this unit.

Is this an instant or controller-based AP?

 

It is Instant. 

Definitely something weird going on with this thing.  If I set to Prefer 5GHz and reboot the device.  Things initially connect at 5GHz, but I am getting very limited throughput.  If disconnect/reconnect the device a few times, I get full throughput.  This also seems to correct itself if I give the device more time after restart.  After firmware update, I did a factory reset too.

The CPU utilization is very low so that is not an issue.  Do I need a support contract to open a case?

 

Update: After another restart with Prefer 5GHz on, devices did not auto connect to 5GHz. Enable/disable wireless on device, then connected at 5GHz and full speed.  Doesn't seem to be any consistency.

What I mentioned for the 802.11ac access points does not apply to instant.

 

- Ultimately the client decides what band it connects to

- "Prefer" tries to steer the client to 5ghz if it observed that the client probed on 5ghz.  If the client insists on connecting to the 2.4ghz after a certain number of association requests the access point allows the client to connect.

- "Force" only allows a client to associate on the 5ghz band if it has observed probles from the client's mac address on the 5ghz band.  If the client insists on connecting on the 2.4ghz band, it will not be able to connect.

- Please again note that it is up to the client what band it associates to ultimately.  Clients may make that decision based on the transmit power of the 2.4ghz vs. the 5ghz band.  It is important to keep the 5ghz band transmit power 6 db above the 2.4ghz band to influence the client's decisions properly.  Otherwise the client will always attempt to choose 2.4ghz regardless.

 

Once again, clients ultimately decide to connect to whatever band they want to based on varying circumstances.  The best thing you can do to influence it is to make sure that the ARM TX power range of the 5ghz band is 6db above the 2.4ghz band.  Everything else like band steering is additional attempts to influence client behavior beyond that, but is not as effective as having the 5ghz band transmit power higher than the 2.4ghz band transmit power.

Colin,

So what I have determined is that the AP behaves completely normal as does the Band Steering setting, but only after about 15 minutes after reboot.  Just after boot, with Band Steering off, devices connect only to 2.4 and at a max throughput of 50Mbps.  I tried a different POE adapter with same results.  I don’t have a POE+ or direct power to test.  I'm wondering if this behavior is a result of some sort of power management.

What is the transmit power of the 2.4ghz vs. the 5ghz?  Band steering just encourages clients to go to 5ghz.  Ultimately the clients make the decision.

 

How are you measuring throughput?  That is a different discussion.

Colin.

Per previous post.  The device is behaving as expected, but only after about 15 minutes of up time.  I have never seen this behavior on other Aruba AP's.  I'm going to get a hold of a power brick and see if that makes a difference.

 

I'm simply using the speed test app on an IOS device for reference.  After 15 minutes, the device switches over to the 5Ghz and I get the full available throughput of 330Mbps.  The behavior is the same whether IOS or Windows PC.

 

It's not a big deal now that I know what to expect.

You should open a TAC case so that they can examine your settings and attempt to replicate what you are observing. There is much info not in this thread that will affect what you are doing like client type, channel width, co-channel interference and density of access points.