we have a wired 802.1x network with cat6500(Hybrid) and cat4000(SUPII). The authentication server is a IAS RADIUS server. So everthing is working fine but on the IAS we have a lot of failed attemps which are filling the log from a client (ab...). So this request is done from the switches where the command "dot1x radius-keepalive" is enabled to check if the servers are alive. To reduce the amount of failed attemps cisco recommand to disable this feature but as soon as we disable the keepalive a failover in case of a radius problem dosen't work anymore. We can unplug the primary server and the request will not be forwarded to the secondary server. As soon as the radius keepalive is enabled again everthing is working. So dos anyone have a idea how we can fix this issue.
