Iptables prevent nmap scanning and binlog

nmap The role of

• Host detection
• Port scanning
• Version checking
• System detection
• Support the writing of detection script

Nmap In practice, the applications are as follows ： 

 

• Audit the security of a device or firewall by detecting it
• Detect the open port of the target host
• Audit network security by identifying new servers
• Detect hosts on the network

  stay Iptables Configuring these commands on can effectively prevent nmap scanning

[[email protected] goaccess-1.5.4]# iptables -t filter -I INPUT -p tcp --tcp-flags ALL FIN,URG,PSH -j REJECT
[[email protected] goaccess-1.5.4]# iptables -t filter -I INPUT -p tcp --tcp-flags SYN,RST SYN,RST -j REJECT
[[email protected] goaccess-1.5.4]# iptables -t filter -I INPUT -p tcp --tcp-flags SYN,FIN SYN,FIN -j REJECT
[[email protected] goaccess-1.5.4]# iptables -t filter -I INPUT -p tcp --tcp-flags ALL SYN -j REJECT
[[email protected] goaccess-1.5.4]# iptables -t filter -R INPUT 1 -s 192.168.80.138 -p tcp --dport 1: --tcp-flags ALL ACK -j REJECT 

  We use kali Tool execution nmap Function scan , Check whether effective defense is achieved

 

  By judgment , This method successfully blocked nmap Scan

binlog

binlog The record of MySQL The database performs all the changes , But not including SELECT and SHOW This kind of operation , Because this kind of operation does not modify the data itself . then , If the operation itself does not cause the database to change , Then the operation will also write Binary system journal

redlog:redo log Weighing and making log files , Used to record changes in transaction operations , It records the value of the data after modification , Whether the transaction is committed or not is recorded . Failed on instance and media （media failure） when ,redo log Documents can come in handy , Such as database power down ,InnoDB The storage engine will use redo log Back to the time before the power down , To ensure the integrity of the data .

difference ：

First of all :redo log Is in InnoDB The storage engine layer generates , and binlog yes MySQL From the top of the database

second ： The two kinds of log records have different content forms .MySQL Of binlog It's a logical log , Its record is corresponding to SQL sentence . and innodb Redo logs at the storage engine level are physical logs .

Third ： The two kinds of logs and records are written to disk at different time points , The binary log is written only once after the transaction commit is completed . and innodb The redo log of storage engine is continuously written in the process of transaction , The log is not written in the order in which the transaction is committed .

Fourth ：binlog It's not recycling , After full write or restart , Will create a new binlog file ,redo log It's recycling .

The fifth ：binlog Can be used as recovery data , Master and slave copy build ,redo log It is used for data recovery after abnormal downtime or media failure .