3月 19

服务器上固态硬盘使用情况追踪测试

2012年8月17日 在服务器上装了一块固态硬盘,当时做了个测试
http://www.simonzhang.net/?p=1298

测试磁盘写能力
time dd if=/dev/zero of=/cache/test.dbf bs=8k count=300000
a

测试磁盘读能力
time dd if=/cache/test.dbf of=/dev/null bs=8k
b

  因为服务器还在工作,并且有20G的左右的缓存数据在使用,能保持这个效率还是不错。

查看一下磁盘健康情况,使用smartmontools工具
# yum install -y smartmontools

常用命令:
健康状况
smartctl -H /dev/hdb
列出错误日志。如果日志量过大,应该尽快更换
smartctl -l error /dev/hdb
所有信息
smartctl -a /dev/hdb

信息里面有温度,加电时间,等详细信息。

附录加载部分
/dev/system/root/ext4 discard,errors=remount-ro,noatime 0 1

3月 08

linux下查看使用硬盘IO过高的进程

  服务器cpu使用率不高,load比较高,所以要查看一下IO。硬盘IO可以通过命令vmstat或iostat获得(也可以用yum 安装dstat获得),网络IO可以用iftop命令获取。但是不知道那个进程使用硬盘IO比较高,通过查找没有找到相关命令,只好自己写个脚本进行统计处理。
  本脚本在CentOS6下(kernel2.6以上)python2.6测试通过。
  直接运行脚本,默认情况下收集3秒钟数据,显示读写最高的前三个进程。如用参数可以使用命令“python fhip.py 4 5 3”,第一个数位每次收集读写数据的间隔秒数,第二个数是打印出读写最多的n个进程,第三个为运行脚本的次数。因为参数部分写的比较简单那,所以用参数必须3个全写。

#!/bin/python 
#-*- coding:utf-8 -*- 
# Filename:    find_high_io_process
# Revision:    1.0 
# Date:        2013-3-8 
# Author:      simonzhang 
# web:         www.simonzhang.net 
# Email:       simon-zzm@163.com 
### END INIT INFO
import os
import re
import sys
import time
from string import strip

####
sys_proc_path = '/proc/'
re_find_process_number = '^\d+$'

####
# 通过/proc/$pid/io获取读写信息
####
def collect_info():
    _tmp = {}
    re_find_process_dir = re.compile(re_find_process_number)
    for i in os.listdir(sys_proc_path):
        if re_find_process_dir.search(i):
            # 获得进程名
            process_name = open("%s%s/stat" % (sys_proc_path, i), "rb").read().split(" ")[1]
            # 读取io信息
            rw_io = open("%s%s/io" % (sys_proc_path, i), "rb").readlines()
            for _info in rw_io:
                cut_info = strip(_info).split(':')
                if strip(cut_info[0]) == "read_bytes":
                    read_io = int(strip(cut_info[1]))
                if strip(cut_info[0]) == "write_bytes":
                    write_io = int(strip(cut_info[1]))
            _tmp[i] = {"name":process_name, "read_bytes":read_io, "write_bytes":write_io}
    return _tmp


def main(_sleep_time, _list_num):
    _sort_read_dict = {}
    _sort_write_dict = {}
    # 获取系统读写数据
    process_info_list_frist = collect_info()
    time.sleep(_sleep_time)
    process_info_list_second = collect_info()
    # 将读数据和写数据进行分组,写入两个字典中
    for loop in process_info_list_second.keys():
        second_read_v = process_info_list_second[loop]["read_bytes"]
        second_write_v = process_info_list_second[loop]["write_bytes"]
        try:
            frist_read_v = process_info_list_frist[loop]["read_bytes"]
        except:
            frist_read_v = 0
        try:
            frist_write_v = process_info_list_frist[loop]["write_bytes"]
        except:
            frist_write_v = 0
        # 计算第二次获得数据域第一次获得数据的差
        _sort_read_dict[loop] = second_read_v - frist_read_v
        _sort_write_dict[loop] = second_write_v - frist_write_v
    # 将读写数据进行排序
    sort_read_dict = sorted(_sort_read_dict.items(),key=lambda _sort_read_dict:_sort_read_dict[1],reverse=True)
    sort_write_dict = sorted(_sort_write_dict.items(),key=lambda _sort_write_dict:_sort_write_dict[1],reverse=True)
    # 打印统计结果
    print "pid     process     read(bytes) pid     process     write(btyes)"
    for _num in range(_list_num):
        read_pid = sort_read_dict[_num][0]
        write_pid = sort_write_dict[_num][0]
        res = "%s" % read_pid
        res += " " * (8 - len(read_pid)) + process_info_list_second[read_pid]["name"]
        res += " " * (12 - len(process_info_list_second[read_pid]["name"])) + "%s" % sort_read_dict[_num][1]
        res += " " * (12 - len("%s" % sort_read_dict[_num][1])) + write_pid
        res += " " * (8 - len(write_pid)) + process_info_list_second[write_pid]["name"]
        res += " " * (12 - len("%s" % process_info_list_second[write_pid]["name"])) + "%s" % sort_write_dict[_num][1]
        print res
    print "\n" * 1


if __name__ == '__main__':
    try:
        _sleep_time = sys.argv[1]
    except:
        _sleep_time = 3
    try:
        _num = sys.argv[2]
    except:
        _num = 3
    try:
        loop = sys.argv[3]
    except:
        loop = 1
    for i in range(int(loop)):
        main(int(_sleep_time), int(_num))

linux查找IO高的进程的源码

1月 29

CentOS 下收集CPU温度

  服务器自动重启,怀疑与温度过高有关。直接检测cpu温度,等重启后,查看是否温度问题。
  操作系统CentOS 6.2 ,内核必须是6.22以上的。使用senosor。

# yum install -y lm_sensors
配置
# sensors-detect

载入模块
# modprobe coretemp

查看温度
# sensors
成功看到CPU温度。

用脚本放在crontab中循环跑,等重启了查查看是否温度过高。
#!/bin/sh
log=’/root/temperature.log’
get_data=`date +’%Y-%m-%d %k:%M’`
echo $get_data >> $log
echo `sensors` >> $log

1月 04

centos下搭建yum服务器自动同步源

  在内网中建立yum服务器,内网linux服务器可以使用yum升级。这样做有两个好处,一内网服务器不用登陆公网比较安全,二节约了流量,不用每台服务器更新都连到公网上。
  安装配置比较简单。需要nginx或apache,本次只列出了nginx配置。还需要rsync工具,建议使用命令“yum install -y rsync”。
  yum服务器内网地址192.168.100.100

Nginx配置

#######################################yum server
server {
        # 直接使用IP地址
        server_name 192.168.100.100;
        # 开启自动显示目录
        autoindex on;
        # 显示文件大小
        autoindex_exact_size off;
        # 显示服务器本地时间
        autoindex_localtime on;
        # yum放置目录
        root    /u01/yumserver/;
        # 内网可见
        allow 192.168.100.0/24;
        # 除上列ip均不能查看
        deny all;
        # 限制ip后会报403错误,做个跳转
        error_page 400 403 404 500 502 503 504 = http://www.simonzhang.net;
        }

同步脚本,将脚本有可执行权限,将此设置到crontab即可。

#!/bin/bash
# -------------------------------
# Revision: 
# Date:        2012-12-11
# Author:      simonzhang
# Email:       simon-zzm@163.com
# Web:         www.simonzhang.net
# ------------------------------- 

# base value
# 要同步的源
YUM_SITE="rsync://mirrors.kernel.org/centos/"
# 本地存放目录
LOCAL_PATH="/u01/mirrors/centos/"
# 需要同步的版本,我只需要5和6版本的
LOCAL_VER="5 5* 6 6*"
# 同步时要限制的带宽
BW_limit=512
# 记录本脚本进程号
LOCK_FILE="/var/log/yum_server.pid"
# 如用系统默认rsync工具为空即可。
# 如用自己安装的rsync工具直接填写完整路径
RSYNC_PATH=""

# check update yum server  pid
MY_PID=$$
if [ -f $LOCK_FILE ]; then
    get_pid=`/bin/cat $LOCK_FILE`
    get_system_pid=`/bin/ps -ef|grep -v grep|grep $get_pid|wc -l`
    if [ $get_system_pid -eq 0] ; then
        echo $MY_PID>$LOCK_FILE
    else
        echo "Have update yum server now!"
        exit 1
    fi
else
    echo $MY_PID>$LOCK_FILE
fi

# check rsync tool
if [ -z $RSYNC_PATH ]; then
    RSYNC_PATH=`/usr/bin/whereis rsync|awk ' ''{print $2}'`
    if [ -z $RSYNC_PATH ]; then
        echo 'Not find rsync tool.'
        echo 'use comm: yum install -y rsync'
    fi
fi

# sync yum source
for VER in $LOCAL_VER;
do 
    # Check whether there are local directory
    if [ ! -d "$LOCAL_PATH$VER" ] ; then
        echo "Create dir $LOCAL_PATH$VER"
        `/bin/mkdir -p $LOCAL_PATH$VER`
    fi
    # sync yum source
    echo "Start sync $LOCAL_PATH$VER"
    $RSYNC_PATH -avrtH --delete --bwlimit=$BW_limit --exclude "isos" $YUM_SITE$VER $LOCAL_PATH$VER
done

# clean lock file
`/bin/rm -rf $LOCK_FILE`

echo 'sync end.'
exit 1

centos_yum_server

客户端配置
编辑/etc/yum.repos.d/CentOS-Base.repo
#base
[base]
name=CentOS-$releasever – Base
baseurl=http://192.168.100.100/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6

#released updates
[updates]
name=CentOS-$releasever – Updates
baseurl=http://192.168.100.100/centos/$releasever/updates/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6

#additional packages that may be useful
[extras]
name=CentOS-$releasever – Extras
baseurl=http://192.168.100.100/centos/$releasever/extras/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6

#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever – Plus
baseurl=http://192.168.100.100/centos/$releasever/centosplus/$basearch/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6

#contrib – packages by Centos Users
[contrib]
name=CentOS-$releasever – Contrib
baseurl=http://192.168.100.100/centos/$releasever/contrib/$basearch/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6

10月 25

阿里云主机 yum 工具报错处理

试用了阿里云主机系统版本:Centos6.2 x64

安装gcc报错:

# yum install gcc

Error: Package: glibc-headers-2.12-1.80.el6_3.5.x86_64 (updates)
Requires: kernel-headers
Error: Package: glibc-headers-2.12-1.80.el6_3.5.x86_64 (updates)
Requires: kernel-headers >= 2.2.1
You could try using –skip-broken to work around the problem
** Found 1 pre-existing rpmdb problem(s), ‘yum check’ output follows:
kernel-2.6.32-220.13.1.el6.x86_64 has missing requires of kernel-firmware >= (‘0’, ‘2.6.32’, ‘220.13.1.el6’)

解决方法:

# vim /etc/yum.conf 注释
“#exclude=kernel*”

去除检查安装软的依赖

开始安装

# yum clean all

# yum install gcc -y