MySQL5.1之前general log不能在運作時啟用或禁用，有時想捕捉SQL來查找問題就很麻煩，偶然間發現一個很不錯的小工具：mysqlsniffer，可以用來捕捉SQL語句，使用幫助如下：
mysqlsniffer --help
mysqlsniffer v1.2 - Watch MySQL traffic on a TCP/IP network
Usage: mysqlsniffer [OPTIONS] INTERFACE
OPTIONS:
--port N Listen for MySQL on port number N (default 3306)
--verbose Show extra packet information
--tcp-ctrl Show TCP control packets (SYN, FIN, RST, ACK)
--net-hdrs Show major IP and TCP header values
--no-mysql-hdrs Do not show MySQL header (packet ID and length)
--state Show state
--v40 MySQL server is version 4.0
--dump Dump all packets in hex
--help Print this
Original source code and more information at:
<a href="http://hackmysql.com/mysqlsniffer">http://hackmysql.com/mysqlsniffer</a>
INTERFACE是指網卡号，如eth0,eth1,lo等。
當然也有人直接tcpdump來捕捉的，方法如下：
tcpdump -i eth1 -s 0 -l -w - dst port 3306 | strings | perl -e '
while(<>) { chomp; next if /^[^ ]+[ ]*$/;
if(/^(SELECT|UPDATE|DELETE|INSERT|SET|COMMIT|ROLLBACK|CREATE|DROP|ALTER)/i) {
if (defined $q) { print "$qn"; }
$q=$_;
} else {
$_ =~ s/^[ t]+//; $q.=" $_";
}
}'
mysqlsniffer is a tcpdump clone specifically for dumping/sniffing/watching MySQL network protocol traffic over TCP/IP networks. mysqlsniffer is coded in C using the pcap library and works with MySQL version 4.0 and newer. mysqlsniffer is the only MySQL-specific network sniffer.
mk-query-digest also understands the MySQL protocol. It’s not a sniffer, though. It reads packet dumps from tcpdump like a slowlog. If you want to analyze queries from the wire (i.e. from network traffic), mk-query-digest is what you want.
For more information about the MySQL protocol read MySQL Internals ClientServer Protocol.
http://hackmysql.com/mysqlsniffer
1、下載下傳軟體包 http://hackmysql.com/code/mysqlsniffer.tgz
2、編譯安裝 root@real1 mysqlsniffer]# gcc -O2 -lpcap -o mysqlsniffer mysqlsniffer.c packet_handlers.c misc.c
如果出現如下提示
請安裝libpcap-devel 包，再重新用gcc來編譯
mysqlsniffer.c:26:18: 錯誤：pcap.h：沒有那個檔案或目錄
[root@real1 mysqlsniffer]# ./mysqlsniffer –help
mysqlsniffer v1.2 – Watch MySQL traffic on a TCP/IP network
–port N Listen for MySQL on port number N (default 3306) ##指定端口
–verbose Show extra packet information ## 顯示包的擴充資訊
–tcp-ctrl Show TCP control packets (SYN, FIN, RST, ACK) ## 顯示tcp包的狀态
–net-hdrs Show major IP and TCP header values ##顯示ip和TCP的頭資訊
–no-mysql-hdrs Do not show MySQL header (packet ID and length) ##不顯示ip和TCP的頭資訊
–state Show state ## 顯示狀态
–v40 MySQL server is version 4.0 ##如果MySQL伺服器版本是4.0 加上此參數
–dump Dump all packets in hex ##把輸入dump成hex檔案格式
–help Print this
示例
./mysqlsniffer eth0 –port 3306 –tcp-ctrl –no-mysql-hdrs
server > 127.0.0.1.24266: Waiting for server to finish response… ::DUMP:: 00 89 b0 f6 J 02 01 00 00 00 aa 00 00 00 f8 7 ‘ 14 10 00 1d b6 c0 00 00 00 00 00 05 00 00 1a 00 00 00 @ 00 00 01 00 00 00 00 00 00 00 00 06 03 s t d 04 1c 00 1c 00 1c 00 w e b d b 00 U P D A T E z y a d s _ s t a t s S E T v i e w s = v i e w s + 6 0 W H E R E d a y = ‘ 2 0 0 9 – 1 1 – 0 8 ‘ A N D z o n e i d = ‘ 3 2 5 ‘ A N D a d s i d = ‘ 1 8 2 ‘ ::DUMP::
127.0.0.1.24266 > server: ACK
127.0.0.1.37968 > server: SYN
server > 127.0.0.1.37968: SYN ACK
127.0.0.1.37968 > server: ACK
server > 127.0.0.1.37968: Handshake <proto 10 ver 5.1.38-Linuxtone.Org-log thd 12629534>
127.0.0.1.37968 > server: Handshake (new auth) <user 0252_liufei db (null) max pkt 1073741824>
server > 127.0.0.1.37968: ACK
server > 127.0.0.1.37968: OK <fields 0 affected rows 0 insert id 0 warnings 0>
127.0.0.1.37968 > server: COM_INIT_DB: webdb
127.0.0.1.37968 > server: COM_QUERY: SET NAMES ‘gbk’
127.0.0.1.37968 > server: COM_QUERY: SET sql_mode=”
127.0.0.1.37968 > server: COM_QUERY: SELECT cpmdeduction,cpcdeduction,cpadeduction,cpsdeduction,cpvdeduction,cpczlink,cpazlink,cpszlink FROM zyads_users
WHERE uid=770 AND status=2 limit 0,1
server > 127.0.0.1.37968: 8 Fields
Field: webdb.zyads_users.cpmdeduction <type tiny int (257) size 3>
Field: webdb.zyads_users.cpcdeduction <type tiny int (257) size 3>
Field: webdb.zyads_users.cpadeduction <type tiny int (257) size 3>
Field: webdb.zyads_users.cpsdeduction <type tiny int (257) size 3>
Field: webdb.zyads_users.cpvdeduction <type tiny int (257) size 3>
Field: webdb.zyads_users.cpczlink <type tiny int (257) size 1>
Field: webdb.zyads_users.cpazlink <type tiny int (257) size 1>
Field: webdb.zyads_users.cpszlink <type tiny int (257) size 1>
End <warnings 0>
|| 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 ||
127.0.0.1.37968 > server: COM_QUERY: SELECT a.adsid,a.url,a.status,adstype,p.planid,p.deduction,p.plantype,p.price,p.priceadv,p.uid,p.expire,p.clearing,p.budget,u.money As advmoney,u.uid AS advuid FROM zyads_ads AS a ,zyads_plan As p ,zyads_users As u
WHERE a.adsid=26 AND a.planid=p.planid AND p.uid=u.uid AND p.status = 1 AND a.status = 3 AND u.status=2 limit 0,1
server > 127.0.0.1.37968: 15 Fields
Field: webdb.a.adsid <type int24 (777) size 9>
Field: webdb.a.url <type var string (509) size 510>
Field: webdb.a.status <type tiny int (2305) size 1>
Field: webdb.a.adstype <type var string (2557) size 20>
Field: webdb.p.planid <type int24 (777) size 8>
Field: webdb.p.deduction <type tiny int (1) size 3>
Field: webdb.p.plantype <type string (2558) size 6>
Field: webdb.p.price <type double (261) size 10>
Field: webdb.p.priceadv <type double (5) size 10>
Field: webdb.p.uid <type int24 (10505) size 8>
Field: webdb.p.expire <type date (33034) size 10>
Field: webdb.p.clearing <type var string (509) size 20>
Field: webdb.p.budget <type long int (259) size 11>
Field: webdb.u.advmoney <type double (5) size 12>
Field: webdb.u.advuid <type int24 (8969) size 8>
|| 26 | http:// | 3 | tw | 3 | 0 | cpc | 0.0000 | 0.1000 | 15 | 0000-00-00 | month | 100000 | 99563626.7179 | 15 ||
127.0.0.1.37968 > server: COM_QUERY: SELECT ip FROM zyads_tempip WHERE ip=’59.60.172.88′ AND planid=3 limit 0,1
server > 127.0.0.1.37968: 1 Fields
Field: webdb.zyads_tempip.ip <type string (2558) size 30>
|| 59.60.172.88 ||
127.0.0.1.37968 > server: COM_QUIT
127.0.0.1.37968 > server: FIN ACK
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