表和链的关系

一共三个表，每个表有好几个链，每个链有很多规则

表和链如下：

filter：INPUT FORWARD OUTPUT
nat：PREROUTING OUTPUT POSTROUTING
mangle：不知道，没用过

常用命令：
iptables
Commands:

  –append  -A chain            #Append to chain
    #在链尾插入一条规则
  –delete  -D chain            #Delete matching rule from chain
  –delete  -D chain rulenum    #删除规则
                                #Delete rule rulenum (1 = first) from chain
  –insert  -I chain [rulenum]  #在特定条目前插入规则
                                #Insert in chain as rulenum (default 1=first)
  –replace -R chain rulenum    #替换某条规则
                                #Replace rule rulenum (1 = first) in chain
  –list    -L [chain [rulenum]]#显示规则
                                #List the rules in a chain or all chains
  –flush   -F [chain]          #清空所有规则 阅读全文 »