摘要:TCP的连接状态对于我们web服务器来说是至关重要的,尤其是并发量ESTAB;或者是syn_recv值,假如这个值比较大的话我们可以认为是不是受到了攻击,或是是time_wait值比较高的话,我们要考虑看我们内核是否需要调优,太高的time_wait值的话会占用太多端口,要是端口少的话后果不堪设想:
先来Review一下:
[[email protected] ~]# netstat -an|awk '/^tcp/{++S[$NF]}END{for(a in S) print a,S[a]}'
TIME_WAIT 99
CLOSE_WAIT 44
FIN_WAIT1 1
FIN_WAIT2 5
ESTABLISHED 275
LAST_ACK 1
LISTEN 25
可以使用man netstat查看TCP的各种状态信息描述:
LISTEN - 侦听来自远方TCP端口的连接请求;
SYN-SENT -在发送连接请求后等待匹配的连接请求;
SYN-RECEIVED - 在收到和发送一个连接请求后等待对连接请求的确认;
ESTABLISHED- 代表一个打开的连接,数据可以传送给用户;
FIN-WAIT-1 - 等待远程TCP的连接中断请求,或先前的连接中断请求的确认;
FIN-WAIT-2 - 从远程TCP等待连接中断请求;
CLOSE-WAIT - 等待从本地用户发来的连接中断请求;
CLOSING -等待远程TCP对连接中断的确认;
LAST-ACK - 等待原来发向远程TCP的连接中断请求的确认;
TIME-WAIT -等待足够的时间以确保远程TCP接收到连接中断请求的确认;
CLOSED - 没有任何连接状态;
我们查看我们设置的Include目录,这下面的*.conf文件都是可以读取的
[[email protected] ~]# grep "Include" /etc/zabbix/zabbix_agentd.conf
### Option: Include
# Include=
Include=/etc/zabbix/zabbix_agentd.d/*.conf
编写配置文件
[[email protected] zabbix_agentd.d]# ls
status.conf tcp_status.sh userparameter_mysql.conf
[[email protected] zabbix_agentd.d]# cat status.conf
UserParameter=tcp.status[*],/etc/zabbix/zabbix_agentd.d/tcp_status.sh "$1"
UserParameter= 后面是key的名称
/etc/zabbix/zabbix_agentd.d 存放脚本的路径
以前的文章有写过,大家可以看我的zabbix板块
编写查看Tcp 状态脚本:
[[email protected] zabbix_agentd.d]# cat tcp_status.sh
#!/bin/bash
#this script is used to get tcp and udp connetion status
#tcp status
metric=$1
tmp_file=/tmp/tcp_status.txt
/bin/netstat -an|awk '/^tcp/{++S[$NF]}END{for(a in S) print a,S[a]}' > $tmp_file
case $metric in
closed)
output=$(awk '/CLOSED/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
listen)
output=$(awk '/LISTEN/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
synrecv)
output=$(awk '/SYN_RECV/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
synsent)
output=$(awk '/SYN_SENT/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
established)
output=$(awk '/ESTABLISHED/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
timewait)
output=$(awk '/TIME_WAIT/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
closing)
output=$(awk '/CLOSING/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
closewait)
output=$(awk '/CLOSE_WAIT/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
lastack)
output=$(awk '/LAST_ACK/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
finwait1)
output=$(awk '/FIN_WAIT1/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
finwait2)
output=$(awk '/FIN_WAIT2/{print $2}' $tmp_file)
if [ "$output" == "" ];then
echo 0
else
echo $output
fi
;;
*)
echo -e "\e[033mUsage: sh $0 [closed|closing|closewait|synrecv|synsent|finwait1|finwait2|listen|established|lastack|timewait]\e[0m"
esac
因为脚本是把tcp的一些信息存放在/tmp/下,为了zabbix可以读取到我们设置zabbix可以读的权限
[root@zhdya02 zabbix_agentd.d]# chmod +x tcp_status.sh
[root@zhdya02 zabbix_agentd.d]# chown zabbix.zabbix /tmp/tcp_status.txt
添加完基本上就是下面这样:
为了方便大家添加,我已经将name和key整理如下. 手动添加即可
Name Key
CLOSED tcp.status[closed]
CLOSE_WAIT tcp.status[closewait]
CLOSING tcp.status[closing]
ESTABLISHED tcp.status[established]
FIN WAIT1 tcp.status[finwait1]
FIN WAIT2 tcp.status[finwait2]
LAST ACK tcp.status[lastack]
LISTEN tcp.status[listen]
SYN RECV tcp.status[synrecv]
SYN SENT tcp.status[synsent]
TIME WAIT tcp.status[timewait]
当然直接导入也可:
链接:http://pan.baidu.com/s/1sle6oNj 密码:oqgs
进行查看
因为tcp连接数不太好设置触发器,因为业务不同,具体设置多少还是要根据需求来。因为我这是个人博客监控所以连接数是多少都可以!