Please take a brief moment to read through this. It details a very frustrating problem I just went through with my Airpoint Pro Outdoor.
I have an Airpoint Pro that I'm using for an access point (AP). The radio worked fine for six months. I had a lightning hit, and needed to replace the radio. Along with putting in the new radio, I also upgraded it to 1.4.5j of the firmware. That day I started having trouble with customers losing connection to the radio. Upon further investigation I found that the link from the radio to the Cisco 3550 switch was dropping in and out. The link light would go dark, the radio will stop responding, and the come back up again. When it did this the radio didn't reboot - it only lost connection to the switch. Setup: The radio is located on top of a 140-foot water tower. It's plugged into a Cisco 3550 switch with about 150 feet of cat-5 cable. Troubleshooting: I was using a 12v power supply at the bottom of the tower. This had always worked fine. But to rule out power loss I put an 18v, 1.67 amp power supply on the bottom. The link still went up and down. So I drug an extension cord up to the top of the tower and put a Smartbridges 12v power supply at the end of the 50 ft cable that is hard-wired to the radio. The link still went up and down. At this point I ruled out power. I replaced the Ethernet cable. Twice. This didn't help. I replaced the Cisco 3550. This didn't help. I have two other radios going into the 3550, one other Airpoint pro and my 5.8 GHz backhaul. Neither of these radios were having trouble, although the 5.8 YDIs would take input errors now and then. I changed the Airpoint Pro out twice. The problem remained consistent across all three different Airpoint Pros. I backreved the firmware. That didn't help. I put on the 1.50 firmware. That didn't help. So yesterday morning I got to digging around in the AirPoint Pro setup. I went to the client info tab and saw connections being established, staying there for five seconds, and then the page going blank. The connections would come back, stay for a few seconds, and then fall back off. The counters on the statistics page would also reset back to zero and start over. So I started fiddling around in the radio's software. The one thing that I had never tried doing was setting the preamble from "short" to "long". (I had been told to change it from the default of "long" to "short", that this was the way to have it set unless you are using non-Smartbridge equipment for CPE, and that Smartbridges recommends setting this parameter to "short", though I don't know why it defaults to "long" if the recommended setting is "short".) As soon as I put the preamble to "long", the clients stopped falling off. It was a miracle. Could it be this easy? I watched this for ten minutes or so, and all seemed well. So I set it back to "short". Immediately the customers started falling off again. So I set it back to "long" and watched it for 30 minutes. All was solid. I drove over to the water tower and watched the link light on the Cisco 3550. It was on solid for the first time in two weeks. I called my wife, and had her set preamble back to "short". As soon as she did the link light on the Cisco 3550 from the radio started dropping off every five seconds or so. As soon as she changed it back to "long" it became solid. I hope this will help someone out. This experience has cost me over $3,000.00 in fees to tower climbers alone, not to mention replacement radios, time, very angry customers, and an enormous amount of personal stress. I'd like to preface the next sentence by pointing out that up until this, I have been very happy with Smartbridges and the performance I have seen out of their product. But I would be less than honest if I didn't add that I am more than a bit miffed that Smartbridges would recommend setting the AP up with the preamble set to "short" and in doing so, cause this level of unreliability. Perhaps the will be addressed on the new and improved web site. :) Thanks Sam The PART-15.ORG smartBridges Discussion List To Join: mailto:[EMAIL PROTECTED] (in the body type subscribe smartBridges <yournickname> To Remove: mailto:[EMAIL PROTECTED] (in the body type unsubscribe smartBridges) Archives: http://198.63.203.6
