cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
12200
Views
5
Helpful
3
Replies

Cisco Aironet 1140 Issues (Dropping clients, 5GHz issue, AP Switching)

G-Money99
Level 1
Level 1

Greetings,

We've been having issues for a while with these Aironet 1140's. We have two of them in the office and the issue is similar to the first issue displayed in this post:

https://supportforums.cisco.com/docs/DOC-26228

The only difference is that I can't do this since we don't use a controller.

We're using Mac clients on Lion/Mt. Lion. We have no issues connecting to the access points, but occassionally the user will drop off one of the AP's(Access Point 2). Recently I changed the setup from TKIP/WPA to AES-CCM/WPA to get the PHY address to 802.11N instead of 802.11G. I got the speeds working fine, but I suppose this caused an issue of people dropping off at different times. I noticed if I remove the SSID from the preferred list and reconnect it goes from WPA to WPA2. Not sure if this is relevant information, just trying to list what I can to resolve this issue. I haven't had any reported issues with the other Access Point(Access Point 1).

Another issue we have is getting the radio to work on 5GHz for Access Point 1. It seems when a user is connected to the 5GHz signal, it will not load any web pages. Can ping out just fine, and ping internally as well. I've checked to see if the client is getting an IP address, and it is. It also has DNS set to 8.8.8.8 and another DNS IP we use. The other Access Point seems to work just fine with 5GHz enabled. Both work with 2.4GHz with no issues at all.

Lastly, clients are not switching Access Points to the strongest signal. I've tried this test with 5+ machines running different OS's from Snow Leopard to Mt. Lion. The client will not switch over passively, the Laptop must be closed and reopened to re-establish the connection to grab the closest signal. This isn't a huge issue, but it's something I'd like to get fixed. This could have been an ongoing issue before I switched the AP's to AES-CCM, but I've only noticed it after the fact.

If there's any additional information needed that could help resolve these issues, let me know.

Thanks!

3 Replies 3

Leo Laohoo
Hall of Fame
Hall of Fame
Lastly, clients are not switching Access Points to the strongest signal. I've tried this test with 5+ machines running different OS's from Snow Leopard to Mt. Lion. The client will not switch over passively, the Laptop must be closed and reopened to re-establish the connection to grab the closest signal. This isn't a huge issue, but it's something I'd like to get fixed. This could have been an ongoing issue before I switched the AP's to AES-CCM, but I've only noticed it after the fact.

The wireless clients/devices decides which WAPs to join.  It's not a "Cisco thing".  It's the standard.

We're using Mac clients on Lion/Mt. Lion. We have no issues connecting to the access points, but occassionally the user will drop off one of the AP's(Access Point 2). Recently I changed the setup from TKIP/WPA to AES-CCM/WPA to get the PHY address to 802.11N instead of 802.11G. I got the speeds working fine, but I suppose this caused an issue of people dropping off at different times. I noticed if I remove the SSID from the preferred list and reconnect it goes from WPA to WPA2. Not sure if this is relevant information, just trying to list what I can to resolve this issue. I haven't had any reported issues with the other Access Point(Access Point 1).

Did you enable WPA and WPA2???  Apple does not like to "choose".  You have to either use WPA OR WPA2.

Another issue we have is getting the radio to work on 5GHz for Access Point 1. It seems when a user is connected to the 5GHz signal, it will not load any web pages. Can ping out just fine, and ping internally as well. I've checked to see if the client is getting an IP address, and it is. It also has DNS set to 8.8.8.8 and another DNS IP we use. The other Access Point seems to work just fine with 5GHz enabled. Both work with 2.4GHz with no issues at all.

The only thing I can think of is the signal strength.  Disable the 2.4 Ghz and see what signal strength you are getting with the 5.0 Ghz.

The wireless clients/devices decides which WAPs to join.  It's not a "Cisco thing".  It's the standard.

That's what I figured, it's just an issue we have been having lately and trying to rule out the possibility it might be an Access Point issue.

Did you enable WPA and WPA2???  Apple does not like to "choose".  You have to either use WPA OR WPA2.

Actually, yes I should have included my steps of trying to resolve the issue. For some reason, the SSID would not appear in the listing of SSID's so I removed the preferred connection, which was WPA, and manually added it to be WPA2 Personal on the client. Still saw some issues with a few users, others seem to have rectified or they're not telling me.

I checked the event logs on the device and saw this:

Packet to client e0f8.4735.c16e reached max retries, removing the client

After some research, it was recommended to raise the packet retry value to 128. I haven't received any complaints from the 3 people that usually complain about dropped wifi yet, but it's still too soon to say.

The only thing I can think of is the signal strength.  Disable the 2.4 Ghz and see what signal strength you are getting with the 5.0 Ghz.

It should not be signal strength since I am about 10 feet away on my test machine which has the issue as well as any other clients in any distance long enough to grab the connection. I will try turning off 2.4 when there's nobody in the office tomorrow in the morning to see if that actually works. I would like to have it dual band though since we're not all at 5GHz here. With this issue, I was actually fearing that there just may be an issue with the 5GHz radio hardware. We also have an extra 1140 laying around I used for testing; the 5GHz radio worked with identical settings to the one not working.

Thanks for the reply! I will take a look at what you suggested a little further and keep this updated if increasing the packet retry value actually rectified the problem just in case someone else has the same issue.

Alex Alvarez
Level 1
Level 1

Try this :

conf t

interface Dot11Radio0

encryption mode ciphers aes-ccm

antenna gain 128

packet retries 128 drop-packet

interface Dot11Radio1

encryption mode ciphers aes-ccm

antenna gain 128

packet retries 128 drop-packet

end

wr mem

And tell us the results!

Review Cisco Networking products for a $25 gift card