1、开启vty

line vty 0 4
authentication-mode scheme user-role network-operator
 protocol inbound ssh

2、创建acl

 ssh server enable
 ssh server acl 2001

3、创建acl条目，指定允许访问的ip

acl number 2001
 rule 0 permit source 192.168.*.* 0
 rule 1 permit source 192.168.*.* 0