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New Member

Two cisco 1131AG at the same time crash the wlan network!

Hi to all

I have a strange problem and need help.

Setup (constellation):

2 Cisco Aironet 1131AG connected to a Zyxel DSL Router with integrated 4 Port Switch, both AP's have the same configuration (with exception IP Adress).

If i patch only one AP it works fine, i see the SSID and i can connect, AP01 or AP02 does not matter, but if i connect/patch both AP's on the Zyxel DSL Router the Port from the AP02 goes down (no flashing) and the Port from AP01 flashing funny (flapp).

No connection to the WebGui is possible and the WLAN SSID can not be found.

Whats that for a strange Problem?!

Thank you in advance for the help

regards,

Beat

Attached the configuration files from AP01 and AP02.

1 ACCEPTED SOLUTION

Accepted Solutions
Silver

Re: Two cisco 1131AG at the same time crash the wlan network!

Assume that the AP is still power up. From my experience, there are two reason why you cannot access the console: low process memory or high CPU. If there is not enough process memory, you should get a message complaining low memory on the console.

From the problem description, it sounds like that the APs are running at high CPU. Some packets are looped between the AP, IOS is designed to pump up the job priority for console once in a while; so that the console will be responsive once in a while; even though the AP is running at high CPU. I assume that the Zyxel does not have port mirroring/monitor session.

I wonder if you can do the followings:

1. console attach to the AP

2. make sure terminal monitor or logging console is enable

3. run debug fastethernet packet xmt or debug fastethernet packet re just before the second AP is powered up

The AP should display the packets looped around. If you can collect the output of show process cpu | exclude 0.00, it will be even better.

5 REPLIES
Silver

Re: Two cisco 1131AG at the same time crash the wlan network!

I suggest that you console attach to the APs when experiecing the problem. Log the console session (In Hyper-terminal, click on "Transfer" and "Capture Tex") and capture the output of show tech in enable mode. I am guessing that the AP is running high CPU. Need more information to narrow down the root cause.

New Member

Re: Two cisco 1131AG at the same time crash the wlan network!

Hi dixho

Thanks for you posting...

The Problem is, i have no Access to the Access Point if both Online...(no ping, no serial console)

regards,

beat

Silver

Re: Two cisco 1131AG at the same time crash the wlan network!

Assume that the AP is still power up. From my experience, there are two reason why you cannot access the console: low process memory or high CPU. If there is not enough process memory, you should get a message complaining low memory on the console.

From the problem description, it sounds like that the APs are running at high CPU. Some packets are looped between the AP, IOS is designed to pump up the job priority for console once in a while; so that the console will be responsive once in a while; even though the AP is running at high CPU. I assume that the Zyxel does not have port mirroring/monitor session.

I wonder if you can do the followings:

1. console attach to the AP

2. make sure terminal monitor or logging console is enable

3. run debug fastethernet packet xmt or debug fastethernet packet re just before the second AP is powered up

The AP should display the packets looped around. If you can collect the output of show process cpu | exclude 0.00, it will be even better.

New Member

Re: Two cisco 1131AG at the same time crash the wlan network!

Hello dixho

Thanks for you reply...

Tomorrow i go to the customer and will proceed your steps..

I'll report...

thanks and regards,

beat

New Member

Re: Two cisco 1131AG at the same time crash the wlan network!

Hi dixho

Better late than never....

I have solved the strange error, the problem was both access points too close...

I move the second AP to a higher floor and tataaaaa...works fine...

Thanks for your help and regards

beat

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