Device management includes the ability to control the number of administrators and management sessions that manage a device. Limiting the number of allowed administrators and sessions per administrator based on account type, role, or access type is helpful in limiting risks related to denial-of-service (DoS) attacks. This requirement addresses concurrent sessions for administrative accounts and does not address concurrent sessions by a single administrator via multiple administrative accounts. The maximum number of concurrent sessions should be defined based upon mission needs and the operational environment for each system. At a minimum, limits must be set for SSH, HTTPS, account of last resort, and root account sessions.
Configure the router to limit the number of concurrent management sessions to an organization-defined number as shown in the example below. R4(config)#ip http max-connections 2 R4(config)#line vty 0 1 R4(config-line)#transport input ssh R4(config-line)#exit R4(config)#line vty 2 4 R4(config-line)# transport input none R4(config-line)#end