1、ACL
Access list, access control lists.
2, the role of
Restrict access to the network address.
3, the main content
Eg：
Router(config)#access-list ?
<1>,
<1-99> IP standard access list
# Standard access control list, the source address can only limit.
<100-199> IP extended access list
# Extended access control lists, limit the source address, destination address, source port, destination port.
<Two>
Router(config)#access-list 1 ?
deny ban
permit allowed
remark marker (no effect)
<Three>
Router(config)#access-list 1 deny ?
ABCD (network);
any (all);
host (a host)
<Four>
Router(config)#access-list 1 deny 192.168.1.2
<Five>, call
Router(config)#interface fastEthernet 0/0
Router(config-if)#ip access-group 1 in
# Description:
In --- restrictions come in
out --- out restrictions
<Six>, attention
Cisco software, in general will be added automatically after 1 deny host 192.168.1.3 access-list access-list 1 deny any. Therefore, after configuration you need to add:
access-list 1 permit any
<Seven>, expand
How do I cancel command has been input?
And re-enter in the front plus no.
Eg：
Router(config)#access-list 1 deny 192.168.1.2
Router(config)#no access-list 1 deny 192.168.1.2
在思科软件中，输入错误的命令后，会自动进行域名解析，因此如何停止或者禁止域名解析？
停止：
Ctrl + “^”或者Ctrl + alt + 6
禁止：
No ip domain lookup!----禁止域名解析
实例：
结果：
