Wireless Access

I've been working on an issue with a group of wireless clients that are having issues with excessive drops in network connectivity. These are Windows machines (4 of them)  running a POS application in a high school environment.

 

These machines attach to a dedicated SSID (WPA2/PSK) on a dedicated AP 105 (e.g. this AP serves up only this SSID for only these 4 machines).

 

There are another 4 APs in the area that service about 220 clients on another SSID (802.1x).

 

When the lunch bell rings these POS machines will lose their network connection. The laptop (connected to the same AP/SSID) I've been using to troubleshoot this drops about 20% of its pings while doing a continuous ping during the same time period.

 

Any thoughts on what I can do to resolve this?

 

Thanks

 

Matt

Does this PODS does just work on 2.4ghz?

 

Can you run

show ap active ip-addr <ap ip address>

 

Check to make sure:
• Channel Frame Retry Rate % is below 30%. If higher then too much
interference.
• Channel Noise Floor is above 80. If Noise Floor is lower then too much
non-802.11 interference

 

Check this on 2.4ghz and also on the 5ghz if you got dual band to see

 

 

Besides this

Does this WLAN  got a vlan deditcated just to that? mean this vlan is not used for nothing else rather than that?

 

The POS machines have draft-n NICs in them. They connect at 65Mbps which seems a bit odd.. Originally they where attached to an AP61 - but I swapped that for a 105 thinking/hoping they had 5Ghz NICs in the clients..

 

I'll check the ap stats on Monday when they're having problems.

 

Yeah - or WLAN is on its own VLANs.

 

I suspect this is some sort of noise/interference issue.

 

Thanks

---

@mcolwell wrote:

The POS machines have draft-n NICs in them. They connect at 65Mbps which seems a bit odd.. Originally they where attached to an AP61 - but I swapped that for a 105 thinking/hoping they had 5Ghz NICs in the clients..

 

I'll check the ap stats on Monday when they're having problems.

 

Yeah - or WLAN is on its own VLANs.

 

I suspect this is some sort of noise/interference issue.

 

Thanks

---

If they are draft-N, they will potentially have trouble with an "N" preamble.  65Mbps is a single stream device.  Most cellphones with "N" connect at this.  I would turn off High Throughput in the HT SSID profile that these devices connect to and see if that stabilizes the connection.

 

Did they also had issues with the AP 65?

 

Did yo try connecting a windows client for example, and see if you get this issue? because if you do must be what collin said... would be a issue bettween the AP and the POD which got a draft N card.

 

Cheers

Carlos

I'll go ahead and disable the HT as you suggest, but I fear it will be of little benefit. These machines had issues maintaining a connection to an AP61.

 

Carlos.. a Windows machine connected to the AP has the same issue.

Then i dont think the issue is the draft n cards you got because if the laptop has the same issue which has normal cards and still got the issue then something else is...

We should correct the issue in the normal windows clients first and then on the pos i think

Can you asnwer my other quetistion i asked you in my first message?

---

@NightShade1 wrote:

Can you asnwer my other quetistion i asked you in my first message?

---

I have to wait untill around 11:30 AM PST to do this.. These machines are only used to serve lunch to our students, so they only operate Monday-Friday around 11:30-12:30(ish).

Here are some stats:

 

Channel 11
Channel Frame Retry Rate(%) 72
Channel Frame Low Speed Rate(%) 0
Channel Frame Non Unicast Rate(%) 1
Channel Frame Fragmentation Rate(%) 0
Channel Frame Error Rate(%) 25
Channel Bandwidth Rate(kbps) 25
Channel Noise 91
BSS Frame Retry Rate(%) 100
BSS Frame Low Speed Rate(%) 0
BSS Frame Non Unicast Rate(%) 0
BSS Frame Fragmentation Rate(%) 0
BSS Frame Receive Error Rate(%) 0
BSS Bandwidth Rate(kbps) 0
BSS Tx Packets 514009
BSS Rx Packets 228506
BSS Tx Bytes 169438564
BSS Rx Bytes 9570272
BSS SNR 25
BSS Tx Rate 1 mbps
BSS Rx Rate 1 mbps

 

 

Channel 11
Channel Frame Retry Rate(%) 35
Channel Frame Low Speed Rate(%) 0
Channel Frame Non Unicast Rate(%) 3
Channel Frame Fragmentation Rate(%) 28
Channel Frame Error Rate(%) 16
Channel Bandwidth Rate(kbps) 205
Channel Noise 91
BSS Frame Retry Rate(%) 22
BSS Frame Low Speed Rate(%) 0
BSS Frame Non Unicast Rate(%) 0
BSS Frame Fragmentation Rate(%) 45
BSS Frame Receive Error Rate(%) 0
BSS Bandwidth Rate(kbps) 192
BSS Tx Packets 514748
BSS Rx Packets 229736
BSS Tx Bytes 169768933
BSS Rx Bytes 9641278
BSS SNR 25
BSS Tx Rate 1 mbps
BSS Rx Rate 54 mbps

 

Channel 11
Channel Frame Retry Rate(%) 69
Channel Frame Low Speed Rate(%) 0
Channel Frame Non Unicast Rate(%) 3
Channel Frame Fragmentation Rate(%) 1
Channel Frame Error Rate(%) 29
Channel Bandwidth Rate(kbps) 31
Channel Noise 91
BSS Frame Retry Rate(%) 0
BSS Frame Low Speed Rate(%) 0
BSS Frame Non Unicast Rate(%) 0
BSS Frame Fragmentation Rate(%) 13
BSS Frame Receive Error Rate(%) 0
BSS Bandwidth Rate(kbps) 6
BSS Tx Packets 514824
BSS Rx Packets 229825
BSS Tx Bytes 169777488
BSS Rx Bytes 9643746
BSS SNR 25
BSS Tx Rate 1 mbps
BSS Rx Rate 54 mbps

Your problem is that there is too much interference.... look at your channel retry rate...

 

Channel Frame Retry Rate(%) 72

 

Channel Frame Retry Rate(%) 35

 

Channel Frame Retry Rate(%) 69

 

For example here on the office we got Also Aruba a few APs

 

Channel                              161
Channel Frame Retry Rate(%)          0

 

 

Channel                              11
Channel Frame Retry Rate(%)          0

 

 

Question

If its a 105 why you just put the 2.4ghz output? 

 

 

Are there many APs near  those? 

The impacted clients are on 2.4Ghz

 

They are what I'm having issues with.

 

Any idea on how to deal with the interference?

Thats why i asked you

Do you have many APS around

Maybe non aruba.... lot of linksys or rogue APS around....

 

can you show me the output of

show wms ap list

There are another 4 Aruba APs in the area that service about 220 clients on another SSID (802.1x).

 

This is actually one of our cleaner campuses. The nearest neighbors are far enough away that we don't generally see them

 

00:0b:86:c2:12:55 1 00:0b:86:a1:25:50 School 40 183 1150 valid 0 TP Ind Arts Office
00:0b:86:c2:12:55 1 00:0b:86:a1:25:53 SDUHSD 40 183 388 valid 0 TP Ind Arts Office
00:0b:86:c2:12:55 1 00:0b:86:a1:25:70 School 3 183 1 valid 0 TP Art IDF
00:0b:86:c2:12:55 1 00:0b:86:a1:25:73 SDUHSD 5 183 1 valid 0 TP Art IDF
00:0b:86:c2:12:55 1 d8:c7:c8:6d:22:f0 School 28 183 2 valid 1 TP IV4 AP105
00:0b:86:c2:12:55 1 d8:c7:c8:6d:22:f1 SDUHSD 28 183 1 valid 0 TP IV4 AP105
00:0b:86:c2:12:57 1 00:0b:86:a1:25:50 School 2 171 0 valid 0 TP Ind Arts Office
00:0b:86:c2:12:57 1 00:0b:86:a1:25:70 School 40 171 19855 valid 20 TP Art IDF
00:0b:86:c2:12:57 1 00:0b:86:a1:25:73 SDUHSD 40 171 761 valid 1 TP Art IDF
00:0b:86:c2:12:57 1 00:24:6c:3e:d1:60 School 8 171 1120 valid 0 TP 92
00:0b:86:c2:12:57 1 00:24:6c:3e:d1:61 SDUHSD 8 171 906 valid 0 TP 92
00:0b:86:c2:40:e7 1 00:0b:86:a4:0e:70 School 40 160 6342 valid 2 TP 96 AP61
00:0b:86:c2:40:e7 1 00:0b:86:a4:0e:71 SDUHSD 40 160 5660 valid 3 TP 96 AP61
00:0b:86:c2:40:e7 1 00:0b:86:ae:45:c0 School 4 160 1614 valid 1 TP GYM Boys Locker
00:0b:86:c2:40:e7 1 00:0b:86:ae:45:c3 SDUHSD 5 160 1044 valid 0 TP GYM Boys Locker
00:0b:86:c2:e1:1a 1 00:0b:86:21:f4:70 School 3 176 787 valid 0 TP Tech Off Hall
00:0b:86:c2:e1:1a 1 00:0b:86:21:f4:73 SDUHSD 4 176 401 valid 0 TP Tech Off Hall
00:0b:86:c2:e1:1a 1 00:0b:86:21:fb:d1 School 19 176 0 valid 0 TP Hall Rm 43
00:0b:86:c2:e1:1a 1 00:0b:86:21:fc:50 School 5 176 1104 valid 0 TP Hall RM 27
00:0b:86:c2:e1:1a 1 00:0b:86:21:fc:53 SDUHSD 5 176 697 valid 0 TP Hall RM 27
00:0b:86:c2:e1:1a 1 00:24:6c:67:64:a0 School 19 176 4301 valid 4 TP-Room48-iso
00:0b:86:c2:e1:1a 1 00:24:6c:67:64:a1 SDUHSD 19 176 2036 valid 0 TP-Room48-iso
00:0b:86:c2:e1:94 1 00:0b:86:21:fb:d1 School 0 180 0 valid 0 TP Hall Rm 43
00:0b:86:c2:e1:94 1 00:0b:86:22:18:80 School 26 180 0 valid 0 TP Coaches Office
00:0b:86:c2:e1:94 1 00:0b:86:22:18:81 SDUHSD 26 180 0 valid 0 TP Coaches Office
00:0b:86:c2:e1:94 1 00:0b:86:a4:0e:70 School 3 180 0 valid 0 TP 96 AP61
00:0b:86:c2:e1:94 1 00:0b:86:a4:0e:71 SDUHSD 5 180 0 valid 0 TP 96 AP61
00:0b:86:c2:e1:94 1 00:0b:86:ae:19:40 School 40 180 54437 valid 6 TP Back of Gym Ceiling
00:0b:86:c2:e1:94 1 00:0b:86:ae:19:43 SDUHSD 40 180 452 valid 1 TP Back of Gym Ceiling
00:0b:86:c2:e1:94 1 00:0b:86:ae:45:c0 School 45 180 0 valid 0 TP GYM Boys Locker
00:0b:86:c2:e1:94 1 00:0b:86:ae:45:c3 SDUHSD 46 180 0 valid 0 TP GYM Boys Locker
00:0b:86:c2:e1:95 1 00:0b:86:a4:0e:70 School 20 150 1 valid 0 TP 96 AP61
00:0b:86:c2:e1:95 1 00:0b:86:a4:0e:71 SDUHSD 18 150 10 valid 0 TP 96 AP61
00:0b:86:c2:e1:95 1 00:0b:86:ae:19:51 foodsvc 40 150 299 valid 1 TPFood
00:0b:86:c2:e1:b3 1 00:0b:86:22:19:a0 School 0 0 0 valid 0 TP RM 409
00:0b:86:c2:e1:b3 1 00:0b:86:22:1c:c0 School 12 157 0 valid 0 TP_Principal
00:0b:86:c2:e1:b3 1 00:0b:86:22:1c:c1 SDUHSD 11 157 0 valid 0 TP_Principal
00:0b:86:c2:e1:b3 1 00:0b:86:ae:1b:30 School 40 157 456 valid 1 TP Admin
00:0b:86:c2:e1:b3 1 00:0b:86:ae:1b:33 SDUHSD 40 157 238 valid 0 TP Admin
00:0b:86:c2:e1:b3 1 00:24:6c:ab:29:50 School 1 157 0 valid 0 TP E109
00:0b:86:c2:e3:d7 1 00:0b:86:ae:3d:70 School 40 201 1840 valid 3 TP E210
00:0b:86:c2:e3:d7 1 00:0b:86:ae:3d:73 SDUHSD 40 201 578 valid 0 TP E210
00:0b:86:c2:e4:0f 1 00:0b:86:21:f5:30 SDUHSD 1 174 1 valid 0 TP Hall Rm 3
00:0b:86:c2:e4:0f 1 00:0b:86:21:f5:31 School 2 174 1 valid 0 TP Hall Rm 3
00:0b:86:c2:e4:0f 1 00:0b:86:21:f5:70 School 15 174 0 valid 0 TP Hall Rm 14
00:0b:86:c2:e4:0f 1 00:0b:86:21:f5:73 SDUHSD 14 174 0 valid 0 TP Hall Rm 14
00:0b:86:c2:e4:0f 1 00:0b:86:21:fb:b0 School 22 174 3 valid 0 TP Hall Rm 35
00:0b:86:c2:e4:0f 1 00:0b:86:21:fb:b0 School 22 174 3 valid 0 TP Hall Rm 35
00:0b:86:c2:e4:0f 1 00:0b:86:21:fb:b3 SDUHSD 23 174 1 valid 0 TP Hall Rm 35
00:0b:86:c2:e4:0f 1 00:0b:86:21:fe:c0 School 2 174 529 valid 1 TP Hall Rm 30
00:0b:86:c2:e4:0f 1 00:0b:86:21:fe:c3 SDUHSD 3 174 130 valid 0 TP Hall Rm 30
00:0b:86:c2:e4:0f 1 00:0b:86:22:00:a0 School 10 174 1 valid 0 TP Hall Rm 23
00:0b:86:c2:e4:0f 1 00:0b:86:22:00:a3 SDUHSD 9 174 1 valid 0 TP Hall Rm 23
00:0b:86:c2:e4:0f 1 00:0b:86:22:00:f0 School 43 174 0 valid 1 TP Hall Rm 32
00:0b:86:c2:e4:0f 1 00:0b:86:22:00:f3 SDUHSD 43 174 0 valid 0 TP Hall Rm 32
00:0b:86:c2:e4:0f 1 00:0b:86:ae:40:f0 School 24 174 1503 valid 0 TP IDF 100
00:0b:86:c2:e4:0f 1 00:0b:86:ae:40:f3 SDUHSD 25 174 599 valid 1 TP IDF 100
00:0b:86:c2:e4:0f 1 00:0b:86:ae:43:70 School 14 174 0 valid 0 TP Rm 13 Wkrm
00:0b:86:c2:e4:0f 1 00:0b:86:ae:43:73 SDUHSD 7 174 0 valid 0 TP Rm 13 Wkrm
00:0b:86:c2:e4:0f 1 00:0b:86:ae:45:b0 School 4 174 0 valid 0 TP LAB 130
00:0b:86:c2:e4:0f 1 00:0b:86:ae:45:b3 SDUHSD 0 174 0 valid 0 TP LAB 130
00:0b:86:c2:e4:0f 1 00:24:6c:41:8e:00 School 0 174 0 valid 0 TP Lecture Hall
00:0b:86:c2:e4:0f 1 00:24:6c:67:63:00 School 28 174 2845 valid 1 TP MC1 AP125
00:0b:86:c2:e4:0f 1 00:24:6c:67:63:01 SDUHSD 28 174 2085 valid 0 TP MC1 AP125
00:0b:86:c2:e4:0f 1 00:24:6c:ab:29:50 School 0 0 0 valid 0 TP E109
00:0b:86:c2:e4:0f 1 d8:c7:c8:6d:21:e0 School 4 174 0 valid 0 TP MC IDF
00:0b:86:c2:e4:0f 1 d8:c7:c8:6d:21:e1 SDUHSD 8 174 0 valid 0 TP MC IDF
00:0b:86:c2:e4:13 1 00:0b:86:21:f4:50 School 2 153 211 valid 0 TP Hall Rm 9
00:0b:86:c2:e4:13 1 00:0b:86:21:f4:53 SDUHSD 2 153 136 valid 0 TP Hall Rm 9
00:0b:86:c2:e4:13 1 00:0b:86:21:f4:70 School 6 153 0 valid 0 TP Tech Off Hall
00:0b:86:c2:e4:13 1 00:0b:86:21:f4:73 SDUHSD 9 153 0 valid 0 TP Tech Off Hall
00:0b:86:c2:e4:13 1 00:0b:86:21:f4:c0 School 0 153 0 valid 0 TP Hall Rm 11
00:0b:86:c2:e4:13 1 00:0b:86:ae:41:30 School 40 153 51488 valid 22 TP Hall Rm 51
00:0b:86:c2:e4:13 1 00:0b:86:ae:41:33 SDUHSD 40 153 552 valid 0 TP Hall Rm 51
00:0b:86:c2:e4:13 1 00:0b:86:ae:41:a0 School 31 153 0 valid 0 TP Hall Rm 54
00:0b:86:c2:e4:13 1 00:0b:86:ae:41:a3 SDUHSD 31 153 0 valid 0 TP Hall Rm 54
00:0b:86:c2:e4:13 1 00:0b:86:ae:43:70 School 18 153 0 valid 0 TP Rm 13 Wkrm
00:0b:86:c2:e4:13 1 00:0b:86:ae:43:73 SDUHSD 17 153 0 valid 0 TP Rm 13 Wkrm
00:0b:86:c2:e4:13 1 00:0b:86:ae:45:b0 School 24 153 0 valid 0 TP LAB 130
00:0b:86:c2:e4:13 1 00:0b:86:ae:45:b3 SDUHSD 23 153 0 valid 0 TP LAB 130
00:0b:86:c2:e4:13 1 d8:c7:c8:6d:21:e0 School 0 153 0 valid 0 TP MC IDF
00:0b:86:c2:e4:1a 1 00:0b:86:21:f4:50 School 10 150 0 valid 0 TP Hall Rm 9
00:0b:86:c2:e4:1a 1 00:0b:86:21:f4:53 SDUHSD 9 150 0 valid 0 TP Hall Rm 9
00:0b:86:c2:e4:1a 1 00:0b:86:21:f4:70 School 2 150 107 valid 0 TP Tech Off Hall
00:0b:86:c2:e4:1a 1 00:0b:86:21:f4:73 SDUHSD 2 150 62 valid 0 TP Tech Off Hall
00:0b:86:c2:e4:1a 1 00:0b:86:21:f5:70 School 1 150 254 valid 1 TP Hall Rm 14
00:0b:86:c2:e4:1a 1 00:0b:86:21:f5:73 SDUHSD 1 150 96 valid 0 TP Hall Rm 14
00:0b:86:c2:e4:1a 1 00:0b:86:ae:41:30 School 27 150 0 valid 0 TP Hall Rm 51
00:0b:86:c2:e4:1a 1 00:0b:86:ae:41:33 SDUHSD 0 150 0 valid 0 TP Hall Rm 51
00:0b:86:c2:e4:1a 1 00:0b:86:ae:41:a0 School 25 150 1297 valid 3 TP Hall Rm 54
00:0b:86:c2:e4:1a 1 00:0b:86:ae:41:a3 SDUHSD 25 150 578 valid 0 TP Hall Rm 54
00:0b:86:c2:e4:1a 1 00:0b:86:ae:45:b0 School 14 150 0 valid 0 TP LAB 130
00:0b:86:c2:e4:1a 1 00:24:6c:67:6b:60 School 34 150 2577 valid 1 TP- Rm 64
00:0b:86:c2:e4:1a 1 00:24:6c:67:6b:61 SDUHSD 34 150 1724 valid 0 TP- Rm 64
00:0b:86:c2:e4:1a 1 d8:c7:c8:6d:21:e0 School 3 150 847 valid 1 TP MC IDF
00:0b:86:c2:e4:1a 1 d8:c7:c8:6d:21:e1 SDUHSD 3 150 486 valid 1 TP MC IDF
00:0b:86:c2:e4:37 1 00:0b:86:21:f4:50 School 8 195 0 valid 0 TP Hall Rm 9
00:0b:86:c2:e4:37 1 00:0b:86:21:f4:53 SDUHSD 8 195 0 valid 0 TP Hall Rm 9
00:0b:86:c2:e4:37 1 00:0b:86:21:f4:70 School 4 195 305 valid 1 TP Tech Off Hall
00:0b:86:c2:e4:37 1 00:0b:86:21:f4:73 SDUHSD 5 195 133 valid 0 TP Tech Off Hall
00:0b:86:c2:e4:37 1 00:0b:86:21:f4:c0 School 11 195 0 valid 0 TP Hall Rm 11
00:0b:86:c2:e4:37 1 00:0b:86:21:f4:c3 SDUHSD 14 195 0 valid 0 TP Hall Rm 11
00:0b:86:c2:e4:37 1 00:0b:86:21:f5:30 SDUHSD 2 195 0 valid 0 TP Hall Rm 3
00:0b:86:c2:e4:37 1 00:0b:86:21:f5:31 School 3 195 0 valid 0 TP Hall Rm 3
00:0b:86:c2:e4:37 1 00:0b:86:21:f5:70 School 0 0 0 valid 0 TP Hall Rm 14
00:0b:86:c2:e4:37 1 00:0b:86:21:fc:50 School 6 195 1262 valid 0 TP Hall RM 27
00:0b:86:c2:e4:37 1 00:0b:86:21:fc:53 SDUHSD 6 195 734 valid 0 TP Hall RM 27
00:0b:86:c2:e4:37 1 00:0b:86:21:fe:c0 School 8 195 0 valid 0 TP Hall Rm 30
00:0b:86:c2:e4:37 1 00:0b:86:21:fe:c3 SDUHSD 10 195 0 valid 0 TP Hall Rm 30
00:0b:86:c2:e4:37 1 00:0b:86:22:00:f0 School 4 195 756 valid 2 TP Hall Rm 32
00:0b:86:c2:e4:37 1 00:0b:86:22:00:f3 SDUHSD 4 195 367 valid 0 TP Hall Rm 32
00:0b:86:c2:e4:37 1 00:0b:86:ae:40:f0 School 12 195 0 valid 0 TP IDF 100
00:0b:86:c2:e4:37 1 00:0b:86:ae:40:f3 SDUHSD 12 195 0 valid 0 TP IDF 100
00:0b:86:c2:e4:37 1 00:0b:86:ae:41:30 School 16 195 0 valid 0 TP Hall Rm 51
00:0b:86:c2:e4:37 1 00:0b:86:ae:41:33 SDUHSD 15 195 0 valid 0 TP Hall Rm 51
00:0b:86:c2:e4:37 1 00:0b:86:ae:43:70 School 25 195 2793 valid 3 TP Rm 13 Wkrm
00:0b:86:c2:e4:37 1 00:0b:86:ae:43:73 SDUHSD 25 195 675 valid 1 TP Rm 13 Wkrm
00:0b:86:c2:e4:37 1 00:0b:86:ae:45:b0 School 4 195 0 valid 0 TP LAB 130
00:0b:86:c2:e4:37 1 00:0b:86:ae:45:b3 SDUHSD 7 195 0 valid 0 TP LAB 130
00:0b:86:c2:e4:37 1 00:24:6c:67:63:00 School 21 195 0 valid 0 TP MC1 AP125
00:0b:86:c2:e4:37 1 00:24:6c:67:63:01 SDUHSD 19 195 0 valid 0 TP MC1 AP125
00:0b:86:c2:e4:37 1 d8:c7:c8:6d:21:e0 School 15 195 7333 valid 3 TP MC IDF
00:0b:86:c2:e4:37 1 d8:c7:c8:6d:21:e1 SDUHSD 15 195 2426 valid 2 TP MC IDF
00:0b:86:c2:e4:4b 1 00:0b:86:21:f4:c0 School 1 205 129 valid 0 TP Hall Rm 11
00:0b:86:c2:e4:4b 1 00:0b:86:21:f4:c3 SDUHSD 2 205 63 valid 0 TP Hall Rm 11
00:0b:86:c2:e4:4b 1 00:0b:86:22:1c:40 School 0 205 0 valid 0 TP 111/112 Wkrm
00:0b:86:c2:e4:4b 1 00:0b:86:ae:41:33 SDUHSD 0 205 0 valid 0 TP Hall Rm 51
00:0b:86:c2:e4:4b 1 00:0b:86:ae:41:a0 School 11 205 0 valid 0 TP Hall Rm 54
00:0b:86:c2:e4:4b 1 00:0b:86:ae:41:a3 SDUHSD 0 205 0 valid 0 TP Hall Rm 54
00:0b:86:c2:e4:4b 1 00:0b:86:ae:45:b0 School 21 205 12391 valid 3 TP LAB 130
00:0b:86:c2:e4:4b 1 00:0b:86:ae:45:b3 SDUHSD 20 205 2508 valid 0 TP LAB 130
00:0b:86:c2:e4:4b 1 00:24:6c:67:6b:60 School 22 205 0 valid 0 TP- Rm 64
00:0b:86:c2:e4:4b 1 d8:c7:c8:6d:21:e0 School 0 205 0 valid 0 TP MC IDF

 

Okay no rogue aps that could be causing interference

I advice you one thing

1-Open a support case with the TAC

 

I will keep helping you but WHILE i telll you other things, to help, start and open a case so you waste less time, i mean in case im not able to help you at all. 

Also the information that we collect it will be useful for the TAC.

So for now you can send them the information of the channel retry rate... so they can see how high is it.

 

Do you have RF protect license?

We could try using the Spectrum analyzer to see if we can find the source of the interference...

 

What you got here is too much 802.11 Interference... or at lesat it looks like it... the noise looks good so there is not too much non 802.11 interference, or really high utilization on the channel?. 

 

 

 

 

Also run and show me the output of

show ap active (this would be nice if you could show the output when users actually connected to the WLAN, dont show me this output when noone is connected please)(also the name of the AP that having issues)

show ap arm history ip-addr <ip address of ap>

show ap arm neighbors ip-addr <ip address of ap>

show ap debug radio-stats ip-addr <ip address of ap> radio 1 advanced | include Busy

 

When showing the output try to use the insert code maybe i can see the output better with that... becasue if you just paste it i wont understand...

 

 

 

 

Another quetions

Your devices are not 5ghz Capable?

 

I had an scenario kind like this... it was a client on a buidlling with lot and lot of neighbor doing him interference... for my luck all his clients or at least 90 % of them were 5ghz capable...  so band steering helped me there... for some reason the other Aruba partner that did that implementation,  configued him just to use the 2.4ghz band... when he had dual band APS....I reconfigured it and use both bands and activated band steering... After that he said that it was much much better and well he was happy with the results.

I showed him the interference and how hight it was on the 2.4ghz with a fluke air checker we got.  And well problem solved but thats in that specific case in which he had almost all the clients capable of 5ghz.

 

The good thing is that he was planning changing to cisco because of it but well now he is not planning that anymore :)

 

Cheers

Carlos

I also find really really weird that just happens to that single AP.

 

This just actuallly to this APs or on some other Areas?

 

If it just happens to THAT single AP you could try changing it to see if it something happening to the AP.   Maybe switching with a good known AP that doesnt give you issues.

> Do you have RF protect license?

 

Nope - we're running Aruba OS 5.x because our controllers wont run 6.x

 

> I also find really really weird that just happens to that single AP.
> This just actuallly to this APs or on some other Areas?

 

It happens a few another areas too. This one is just my biggest headache now because it's slowing down our lunch lines... this is also the area where the problem seems to be the worst.

 

> If it just happens to THAT single AP you could try changing it to see if it something happening to the AP.   Maybe switching with a good known AP that doesnt give you issues.

 

I've already done that.

Do you have drop broadcast and multicast configured on all your virtual APS?
If your PSK wlan only services 2.4 GHz clients please make sure in the virtual AP it is only broadcasting on the g band. Can you also make sure that PSK network is only being broadcast on the access points that need them by using ap groups?

Dropping broadcasts will decrease contention, retries and congestion.
Only broadcasting in the 2.4 band will decrease management overhead.
Only broadcasting that wlan on the access points that need it will reduce management overhead, as well.


You could have a contention issue

Thanks Colin,

 

> Do you have drop broadcast and multicast configured on all your virtual APS?

Yes... they drop broadcast/multicast

> If your PSK wlan only services 2.4 GHz clients please make sure in the virtual AP it is only broadcasting on the g band.

I'll make that change... Currently it's doing A/B/G

 

> Can you also make sure that PSK network is only being broadcast on the access points that need them by using ap groups?

It's already setup that way.

 

Would Airwave shed any light on these issues? I'm running it in eval mode right now, so I'm still learning how to drive it.

 

-Matt

Airwave can give you more statistics about the access point rf performance if you have the "mgmt-server type amp primary" command executed on the controller.

It seems like you have congestion and/or contention. The medium only has a limited bandwidth for traffic and things like interference, a large number of users, management overhead and traffic decrease that.

How many users connect to that access point when traffic is at its peak?

I've posted some of the info Nightshade was asking for - please see the attachment.

 

> How many users connect to that access point when traffic is at its peak?

 

3 users are connected

I got a qeustion to you

Does this happen always at any hour?

You said that when the bell rings this pos loose conectivity....if you are with your laptop let say really in the morming when noone is using the POS do you still see the problem?

 

When you run the command

show ap active ip-addr <ap ip address>

IT will show you the actual noise that it see at that momment... you should try run it many times when you see the issue... to see if you still see non 802.11 interference.

 

It would be nice if you had an airchecker from fluke.... it can tell you the channel utilization, interference and other good stuff when you do not have the RF licnse for the spectrum analysis...

 

I saw the output that you gave me and defenely its interference... the

show ap debug radio-stats ip-addr 172.22.140.118 radio 1 advanced | include Busy

Its above 20 which means interference.

 

Now inotice you ran the commands at different hours.... the uptime of the AP is 21mins... and when you reboot the AP or something like it you wont see the arm history of the AP... it will be wiped....

Did you reboot it? or something happened to the AP?

 

Collin is right its really hard to troublehshoot it if you dont even have spectrum analyzer to see whats happening...

 

 

> Now inotice you ran the commands at different hours.... the uptime of the AP is 21mins... and when you reboot the AP or something like it you wont see the arm history of the AP... it will be wiped....

Did you reboot it? or something happened to the AP?

 

I had flipped it over to an air monitor hoping I could see some if there was some rouge device out there.

 

I'll get a case going.

I hope you have a case open because there are quite a few pieces missing. If there are only three users connected to that access point in total, you need to ensure that you are dropping broadcasts for all virtual APS, you do not have unacceptable ref interference, or there is nothing between your access point and the users like metal or metal mesh that could be causing 70% retries. I do not think we can help you here if you do not open a case. We would be just guessing.