Wireless Access

Hi all,

 

As we dont have many rogue AP's around, i have disabled ARM, and am using manual settings for my radios.

 

However, i have noticed a difference in what i have set, and what (i believe) is being transmitted...

This is what is showing under Access Point...

 

And this is what is set in the AP config...

 

 

Throughput seems ok on all clients etc, so im not really sure how or what the settings sgould be to get maximum performace.

 

Apologies for all of the questions..Just learning!!

 

Thanks!

Depending on the access point, there are regulatory power constraints.  On the commandline, type "show ap allowed-max-eirp"

Well, ive tried the CLI but for some reason it wont let me access it as its says my password is invalid, even though i havent changed anything like that on the AP yet.

 

:(

Long story short, if you want an access point at maximum power, max will accomplish that in a single AP deployment. If you are it for more than what the regulatory domain calls for on that channel, it will limit it to that power.

Ah ok, so max is power is dependant on actual channel number eg 36 or 100 etc on 5ghz?

...and AP model number and if you are bonding channels or not.  Here is the output from a 225 (scroll to see everything...there are alot of columns):

(Aruba7005-US) #show ap allowed-max-EIRP ap-name Main-225

Max EIRP setting for AP-225
---------------------------
Channel  1   2   3   4   5   6   7   8   9   10  11  12  13  14  36  40  44  48  52  56  60  64  100  104  108  112  116  120  124  128  132  136  140  144  149  153  157  161  165
-------  -   -   -   -   -   -   -   -   -   --  --  --  --  --  --  --  --  --  --  --  --  --  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---
b        29  29  29  29  29  29  29  29  29  29  29  *   *   *   *   *   *   *   *   *   *   *   *    *    *    *    *    *    *    *    *    *    *    *    *    *    *    *    *
g/a      32  32  32  32  32  32  32  32  32  32  32  *   *   *   21  21  21  21  28  28  28  28  28   28   28   28   28   *    *    *    27   27   27   27   33   33   33   33   33
HT 20    32  32  32  32  32  32  32  32  32  32  32  *   *   *   21  21  21  21  27  28  28  28  28   28   28   28   28   *    *    *    27   27   27   27   33   33   33   33   33
HT 40    32  32  32  32  32  32  32  32  32  32  32  *   *   *   20  20  20  20  24  24  24  24  24   24   24   24   *    *    *    *    24   24   24   23   32   32   32   32   32
VHT 80   *   *   *   *   *   *   *   *   *   *   *   *   *   *   21  21  21  21  21  21  21  21  21   21   21   21   *    *    *    *    21   21   21   20   33   33   33   33   33

The technical answer (but not all encompassing answer) for all of this is in the thread here;  http://community.arubanetworks.com/t5/Unified-Wired-Wireless-Access/AP-275-emitting-power/m-p/192051/highlight/true#M38612

Ok, interesting, however, that means my IAP215 should be outputting more than it is showing, especially if what it shows is the actual EIRP?

 

 

According to the spec sheet on the Aruba website, it states a maximum of 23dbi plus antenna gain for EIRP for both the 2.4 & 5 radios of 5dbi each 

 

With that, i thought i would be getting closer if not the maximum when set manually as our UK maximum is 30.

 

 

Also.... my AP is currently ARM on channel 116E.

 

What is the 'E'?

 

Thanks!

 

The chart above is for the AP 225 (I don't have an AP 215).  If you can run the command on the commandline of your IAP you will get a chart for that AP's model

 

The E means 80 mhz channel.  Quite frankly, if you cannot get the commandline, you will not have the information needed to explain the output and you will probably have to trust us...

 

No. i totally trust what you are saying!

 

Its more of me understanding how things work etc.

 

I am a complete a complete novice with Aruba (and detailed netwroking)!

 

As for the CLI, for some reason in terminal on OSX, i can ssh the IP address, but it says permission denied when i put in the defaul password.

Are you using the admin username?

 

yes, admittedly i haven't changed any of those settings yet, however, i tried changing just the password and still no luck.

 

ssh & cli are all enabled too.

Not sure if this is a bug or not....

 

 

[IMG]http://i546.photobucket.com/albums/hh418/jasons6930/2015-12-13%2005.38.41%20pm_zps1bf774aj.png[/IMG]

Just a quick note, the per-chain max power is 18dBm. The 215 is a 3x3 AP which means with MRC the second chain adds another 3dB and the 3rd chain adds 1.8dB, so we say it's a 23dBm max power ouput. Plus the 5dBi antenna gain will give you a maximum power output of 28dBm in 3x3. Note that in most cases, the regulatory maximum is above what the AP can do, and we will allow you to plug in absurdly large numbers and the APs will just go as powerful as they can go. So even when you configure 30dB EIRP, the 215 will only be able to ever do 23dB per chain, or 28dB with all three chains. 

If the regulatory max is BELOW the max power capability of the AP, then the AP will power down the radio the required amount to stay within the limit. So for Ch 36, where the max HT20 power is 21dB, the radio config will look like this:

 

Radio Power = 16

Antenna = 5dBi

Rated max gain = 21dBm (per chain) EIRP or 26dBm effective MIMO power output with all three chains

 

The *ACTUAL* per chain power of the AP will be 16dB, and with antenna gain, that puts you at the regulatory max for HT20 on Ch 36. 

edit: brain fart on the MRC, meant MIMO power. Fixed the math too, shouldn't make posts on weekends.

Thanks Jerrod,

 

I now understand how this works!

 

But, with that all in mind, my AP will not output at 28dB regardless of if i have it set to ARM or manual with it set to max.

 

Do you think this may be firmware issue?

 

 

I have also noticed that if the AP changes channel, nearly all clients that are connected are disassociated, but then do not associate again without having to open up wifi settings.

 

Just to add that we are an all OSX & iOS household and iphones in particular are showing fairly weak signal levels.

 

At the moment, ARM has it set to Ch116E.

 

jason.

 

 

What country are you working out of (sorry if it's been stated before). Here is my 215 IAP

#####

215-livingroom# show ap bss-table

Aruba AP BSS Table
------------------
bss ess port ip phy type ch/EIRP/max-EIRP cur-cl ap name in-t(s) tot-t
--- --- ---- -- --- ---- ---------------- ------ ------- ------- -----
ac:a3:1e:d7:8b:70 ext-lab ?/? 192.168.100.136 a-VHT ap 52E/23/23 0 215-livingroom 0 33d:5h:44m:18s
ac:a3:1e:d7:8b:71 zulu ?/? 192.168.100.136 a-VHT ap 52E/23/23 7 215-livingroom 0 33d:5h:44m:18s
ac:a3:1e:d7:8b:60 ext-lab ?/? 192.168.100.136 g-HT ap 6/23/23 1 215-livingroom 0 33d:5h:44m:18s
ac:a3:1e:d7:8b:61 zulu ?/? 192.168.100.136 g-HT ap 6/23/23 6 215-livingroom 0 33d:5h:44m:17s

215-livingroom# show ap allowed-max-EIRP

Max EIRP setting for AP-215
---------------------------
Channel 1 2 3 4 5 6 7 8 9 10 11 12 13 14 36 40 44 48 52 56 60 64 100 104 108 112 116 120 124 128 132 136 140 144 149 153 157 161 165
------- - - - - - - - - - -- -- -- -- -- -- -- -- -- -- -- -- -- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- ---
b 28 28 28 27 27 27 27 27 27 27 27 * * * * * * * * * * * * * * * * * * * * * * * * * * * *
g/a 28 28 28 27 27 27 27 27 27 27 27 * * * 21 21 21 21 26 26 26 26 26 26 26 26 26 * * * 26 26 26 26 27 27 27 27 27
HT 20 27 27 27 27 27 27 27 27 26 26 26 * * * 21 21 21 21 27 27 27 27 27 27 27 27 27 * * * 27 27 27 27 26 26 26 26 26
HT 40 28 28 28 27 27 27 27 27 27 27 27 * * * 21 21 21 21 26 26 26 26 26 26 26 26 * * * * 26 26 26 26 27 27 27 27 27
VHT 80 * * * * * * * * * * * * * * 21 21 21 21 26 26 26 26 26 26 26 26 * * * * 26 26 26 26 26 26 26 26 26
#####

 

Mine is maxing out at the 23dBm per branch at Ch6 and 52E. I have my min set to 27 and max set to max. 

Also let me hit up PLM to see if the IAPs reflect transmit power with or without accounting for antenna gain in the CLI. 

So we do no accounting for MRC, all calculations are configured for per-chain. See the radio power ouput log from the IAP-215

 

215-livingroom# show log driver | include Power

[  132.227810] Mon Dec 14 00:57:12 2015:223        26.186026 wifi1: EIRP (Config: 24.0dBm, Set: 23.0dBm, AP Max: 23.0dBm, Reg Max: 27.0dBm), Conducted Power Set: 18.0dBm, Gain: 5.0

132        24.965199 wifi0: EIRP (Config: 24.0dBm, Set: 23.0dBm, AP Max: 23.0dBm, Reg Max: 27.0dBm), Conducted Power Set: 18.0dBm, Gain: 5.0

223        26.186026 wifi1: EIRP (Config: 24.0dBm, Set: 23.0dBm, AP Max: 23.0dBm, Reg Max: 27.0dBm), Conducted Power Set: 18.0dBm, Gain: 5.0

215-livingroom#

 

You can see that the config is set to 18dBm per chain, with 5dBi antenna gain for a per-chain max of 23dBm. You can effectively think of there being an additional 4.8dB of MRC for 3x3. But if you are seeing 23dBm as the radio output power, you are indeed at the max.

Thanks very much for your time explaining and investigating my issue, especially on the weekend!

 

I live in the UK so (from memory) the max we can have is 30dBi (if i understand correctly).

 

However, in the spec for the 215, it clearly states 23dBi plus antenna gain which, as you say maxes at 28.

 

My AP is installed upstairs in the house and the problem i have is that signal drops in a couple of areas where before with my previous AP, gave good coverage.

 

Maybe i should invest and install one downstairs as well as this is were coverage is affected?

If the CLI states your AP is at 23 and you run the commands to see that the channels you are in are at 30, then your AP is indeed at 28. That said, depending on how you have it mounted can drastically impact how the RF propagates throughout the house. Is it mounted on the ceiling upstairs or is it sitting on a desk? Is it in a corner? Is there some dense furniture on it? etc? 

The old one and the new one likely have widely varying propagation properties, you may need to re-mount your 215 on a ceiling, or move it to change the propagation. Or install a second one. I have four in my house (2x215 and 2x205) to cover three floors (one on the second floor, two on the first floor, one in the basement). At a minimum, I still need two (one upstairs and one downstairs). If I mounted them properly instead of setting them on furniture, I would definately ONLY need two. :)

Ok thanks.

 

I still cant access the CLI via terminal however, i think this is probably the same from the Support drop down?

 

*********************************************************************************************************
 12/14/2015 14:13:28 PM    Target: Aruba    Command: show ap allowed-max-EIRP 
*********************************************************************************************************

Max EIRP setting for AP-215
---------------------------
Channel  1   2   3   4   5   6   7   8   9   10  11  12  13  14  36  40  44  48  52  56  60  64  100  104  108  112  116  120  124  128  132  136  140  144  149  153  157  161  165
-------  -   -   -   -   -   -   -   -   -   --  --  --  --  --  --  --  --  --  --  --  --  --  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---  ---
b        17  17  18  18  18  18  18  18  19  19  19  19  19  *   *   *   *   *   *   *   *   *   *    *    *    *    *    *    *    *    *    *    *    *    *    *    *    *    *
g/a      19  19  19  19  19  19  19  19  19  19  19  19  19  *   21  21  21  21  21  22  22  22  23   23   23   23   23   23   23   23   23   23   23   *    *    *    *    *    *
HT 20    18  18  18  18  18  18  18  18  18  18  18  18  18  *   21  21  21  21  21  21  21  21  23   23   23   23   23   23   23   23   23   23   23   *    *    *    *    *    *
HT 40    19  19  19  19  19  19  19  19  19  19  19  18  18  *   22  22  22  22  22  22  22  22  23   23   23   23   24   24   24   24   24   24   24   *    *    *    *    *    *
VHT 80   *   *   *   *   *   *   *   *   *   *   *   *   *   *   22  22  22  22  22  22  22  22  22   22   22   23   23   23   23   23   23   23   23   *    *    *    *    *    *

 

 

So, at the moment, i am on ch52 on 5G and the log gives me this...

 

Interface :wifi0
ARM History
-----------
Time of Change       Old Channel  New Channel  Old Power  New Power  Reason
--------------       -----------  -----------  ---------  ---------  ------
2015-12-14 12:42:30  52E          52E          Max        24         P-

 

What i am trying to understand is why the MAX EIRP for this channel in the UK is 22, and yet this history shot gives me a power set at 24?

 

Does the Antenna gain get added to this and if so, i assume the AP pulls it back down to 28 but none of the interfaces actually state that?

 

Having said that, the WEB UI under Access point gives me this!....

 

 

And after reading your previous post i have found this...

 

40:e3:d6:41:da:61  PN    ?/?   192.168.2.88  g-HT   ap    13-/19/19         6       Aruba    0        1h:50m:8s
40:e3:d6:41:da:70  PN5G  ?/?   192.168.2.88  a-VHT  ap    52E/22/22         3       Aruba    0        1h:13m:35s

 

I think what is confusing me a little is all the different power levels i am seeing in the different sections!

 

I really do appreciate you helping me out here, as i am a noob to the Aruba product, and a bit of a noob with wifi!

 

 

In the ARM History output, that's just the ARM setting, NOT the radio power. ARM can say it's putting the radio at 24 or 30 or 127, doesn't mean the radio actually goes to that amount. 

 

The ones to watch are in your GUI short or in the show ap bss-table, that shows you what the radio is actually set to. You can also capture the output of 'show log driver | include Power' and you will see just what the AP is setting. Copy of my output is below.

 

215-livingroom# show log driver | include Power

[  132.227810] Mon Dec 14 00:57:12 2015:223        26.186026 wifi1: EIRP (Config: 24.0dBm, Set: 23.0dBm, AP Max: 23.0dBm, Reg Max: 27.0dBm), Conducted Power Set: 18.0dBm, Gain: 5.0

132        24.965199 wifi0: EIRP (Config: 24.0dBm, Set: 23.0dBm, AP Max: 23.0dBm, Reg Max: 27.0dBm), Conducted Power Set: 18.0dBm, Gain: 5.0

223        26.186026 wifi1: EIRP (Config: 24.0dBm, Set: 23.0dBm, AP Max: 23.0dBm, Reg Max: 27.0dBm), Conducted Power Set: 18.0dBm, Gain: 5.0

215-livingroom# 

 

You should see something like this in your last line:

wifi1: EIRP (Config: 24.0dBm, Set: 22.0dBm, AP Max: 23.0dBm, Reg Max: 22.0dBm), Conducted Power Set: 17.0dBm, Gain: 5.0

Fantastic, that expalins it perfectly and i thank you for your valuable input!

 

If i were to add another AP to the downstairs, would this cause any confilcts with the upstairs?

 

The reason i ask, is that i did originally have two AP's one up and one down.

 

One was approx 2/3 meters above positioned centrally in the house, the other albeit with a plasterboard ceiling, wooden flooring and carpet between them also positioned centrally. No matter how hard i tried and how many times i adjusted power settings etc, i just kept getting clients hopping around all over the place with constant roaming until eventually they gave up and dropped off completely.

 

They would both be connected via a ethernet/poe.

 

Would the ARM function successfully manage the two independantly of each other but allow roaming?

 

I assume thats how you have yours set up, especiialy with 4!!

 

Regards

Jason.

Correct. ARM will handle the channels and power and client-match should keep the clients stable. You can adjust power if needed. Also making sure that if you run full DFS channels that your clients also support it is a must. Otherwise, just remove the channels your clients don't support (if you run in to that) will help keep your clients stably on a single AP. 

Yes, we mainly have newish clients (99% iOS & OSX).

 

But, selfishly (?) I have two networks set up, one 2.4 for the family, and a 5 for myself and all my work computers etc.

 

So, it will only be mine that will have DFS concerns and they seem to be ok with those!

 

Lastly, is it worth me disabling the lower channels on the 5G band (112 and below uk) to force the AP onto the higher power setting ones?

 

 

So long as you have channel availability and there's no interference in the upper bands, go for it. :)

Ok great!

 

Many thanks for all of your help.

 

I'll leave you alone.

 

 

 

 

 

 

 

For now!

 

:))

 

Jason.