安装clamav

###第一步：Clamav下载
http://www.clamav.net/downloads   
wget http://www.clamav.net/downloads/production/clamav-0.99.2.tar.gz

###第二步：创建clamav用户和组
groupadd clamav   (创建clamav组)
useradd -g clamav clamav(创建clamav用户并加入clamav组)

###第三步：编译安装
```shell
tar -xf clamav-0.99.2.tar.gz
cd clamav-0.99.2

安装依赖包
yum install gcc openssl openssl-devel  -y

./configure--prefix=/usr/local/clamav
make&&make install
```

###第四步：配置
```shell
mkdir /usr/local/clamav/logs      #(日志存放目录)
touch /usr/local/clamav/logs/clamd.log
touch /usr/local/clamav/logs/freshclam.log
mkdir /usr/local/clamav/updata   #(clanav 病毒库目录)
chown -R root.clamav /usr/local/clamav/
chown -R clamav.clamav /usr/local/clamav/updata/
  
chown clamav.clamav /usr/local/clamav/logs/clamd.log
chown clamav.clamav /usr/local/clamav/logs/freshclam.log

cd /usr/local/clamav/etc
cp clamd.conf.sample clamd.conf
cp freshclam.conf.sample freshclam.conf

vim clamd.conf
#Example    注释掉这一行.
LogFile /usr/local/clamav/logs/clamd.log    
PidFile /usr/local/clamav/updata/clamd.pid     
DatabaseDirectory /usr/local/clamav/updata

vim freshclam.conf
#Example    注释掉这一行.  
DatabaseDirectory /usr/local/clamav/updata
UpdateLogFile /usr/local/clamav/logs/freshclam.log
PidFile /usr/local/clamav/updata/freshclam.pid
```

###第五步：升级病毒库
/usr/local/clamav/bin/freshclam

PS:这个过程很久，大概半个小时。确保网络正常

```shell
--help / -h              show help
--version / -V           print version number and exit
--verbose / -v           be verbose
--debug                  enable debug messages
--quiet                  only output error messages
--no-warnings            don't print and log warnings
--stdout                 write to stdout instead of stderr
--show-progress          show download progress percentage
--config-file=FILE       read configuration from FILE.
--log=FILE / -l FILE     log into FILE
--daemon / -d            run in daemon mode
--pid=FILE / -p FILE     save daemon's pid in FILE
--user=USER / -u USER    run as USER
--no-dns                 force old non-DNS verification method
--checks=#n / -c #n      number of checks per day, 1 <= n <= 50
--datadir=DIRECTORY      download new databases into DIRECTORY
--daemon-notify[=/path/clamd.conf]   send RELOAD command to clamd
--local-address=IP / -a IP    bind to IP for HTTP downloads
--on-update-execute=COMMAND   execute COMMAND after successful update
--on-error-execute=COMMAND    execute COMMAND if errors occured
--on-outdated-execute=COMMAND execute COMMAND when software is outdated
--list-mirrors           print mirrors from mirrors.dat
--enable-stats           enable statistical information reporting
--stats-host-id=UUID     HostID in the form of an UUID to use when submitting statistical information
--update-db=DBNAME       only update database DBNAME
```



###第六步：杀毒
/usr/local/clamav/bin/clamscan -r --remove (查杀当前目录并删除感染的文件)
/usr/local/clamav/bin/clamscan -r --bell -i / （扫描所有文件并且显示有问题的文件的扫描结果）

>其他参数
>```shell
>   -r/--recursive[=yes/no] 所有文件
>　　--log=FILE/-l FILE  增加扫描报告
>　　# clamscan -l /var/log/clamscan.log /
>　　--move [路径] 移动病毒文件至..
>　　--remove [路径] 删除病毒文件
>　　--quiet  只输出错误消息
>　　--infected/-i 只输出感染文件
>　　--suppress-ok-results/-o 跳过扫描OK的文件
>　　--bell   扫描到病毒文件发出警报声音
>　　--unzip(unrar) 解压压缩文件扫描
>```

###第七步：计划任务
实际生产环境应用
一般使用计划任务，让服务器每天晚上定时跟新和定时杀毒。保存杀毒日志，我的crontab文件如下
16 4 * * *         /usr/local/clamav/bin/freshclam
16 5 * * *         /usr/local/clamav/bin/clamscan  --infected  -r /  --remove -l /var/log/clamscan.log





>返回值
>0 : 无病毒
>1 : 发现病毒
>40: 已经通过的未知选项
>50: 数据库初始化错误
>52: 不支持的文件格式
>53: 无法打开目录
>54: 不能打开文件(ofm)
>55: 读文件错误(ofm)
>56: Can't stat input file / directory.
>57: Can't get absolute path name of current working directory.
>58: I/O 错误, 请检查文件系统
>59: 无法在/etc/passwd获得当前用户的信息
>60: 无法在/etc/passwd获得'clamav'（默认名）用户的信息
>61: Can't fork.
>63: 不能创建临时文件/目录(检查权限).
>64: 无法对临时目录进行写操作 (请指定另一个目录).
>70: 无法分配或释放内存 (calloc).
>71: 无法分配内存 (malloc).






```shell
NOTE:
Problem:
"Update failed. Your network may be down or none of the mirrors listed in  /usr/local/etc/freshclam.conf is working. Check http://www.clamav.net/doc/mirrors-faq.html for possible reasons."

Resolve:
from freshclam.conf file find the line
#DatabaseMirror db.XY.clamav.net and uncomment it out to
DatabaseMirror db.us.clamav.net
#or DatabaseMirror db.ac.clamav.net
```