Awhile back, we had a problem with two of our Cisco Aironet devices at a customer site that kept dropping their wireless connection to each other.  The old radios had been replaced by these newer aironet devices while still keeping the same antennas.

The error message, among many, in the logs stated: “Packet to client <clientname> reached max retries, removing the client”.

At first, we thought that they might be overshooting the other end by having their signal strength too high.  We tried lowering the signal strength but it didn’t really help the issue that much.  We tried scanning the airwaves for interference, but couldn’t decisively find anything troublesome with the channel frequencies.  We also checked the alignment of the antennas and saw that they appeared to be in the same position that they had been for quite some time.

I came across a wireless troubleshooting guide by Cisco that mentioned that the problem can be an indication of a bad RF. It suggested putting the command “packet retries 128 drop-packet” on both access points as a workaround for bad RF.  After this command was applied, we the wireless connection stopped disconnecting.