초보의 공간

리눅스 서버는 살아 있는데,

특정 프로세스만 Down 되어 서비스가 먹통이 되는 때가 간혹 있다.

예를들어, 서버의 ICMP는 되나 nginx만 죽었다던지...그런 것이다.

방법을 찾던 중에 Monit 이라는 오픈소스를 알게 되었다.

- 설치

# On RedHat/CentOS(AMI)/Fedora/

yum install monit

# On Ubuntu/Debian/Linux Mint

apt-get install monit

# vi /etc/monit.conf   또는  vi /etc/monit/monitrc

주석 처리 된 내용 중 원하는 설정의 # 을 제거하여 활성화 한다.

set daemon  120           # check services at 2-minute intervals

check process mysqld with pidfile /var/run/mysqld/mysqld.pid
group mysql
start program = "/etc/init.d/mysqld start"
stop program = "/etc/init.d/mysqld stop"
if failed host 127.0.0.1 port 3306 then restart
if 5 restarts within 5 cycles then timeout

monit -t
Control file syntax OK

참고 url : https://mmonit.com/monit/documentation/monit.html

https://nolboo.kim/blog/2016/08/13/monitoring-linux-monit/

Mikrotik Router SYN flood Protection

New Terminal

[Mikrotik]# 아래 내용 적용.

ip firewall filter add chain=input protocol=tcp connection-limit=0,32  action=add-src-to-address-list  address-list=blocked-addr address-list-timeout=1d

ip firewall filter add chain=input protocol=tcp src-address-list=blocked-addr connection-limit=3,32 action=tarpit  

ip firewall filter add chain=forward protocol=tcp tcp-flags=syn connection-state=new action=jump jump-target=SYN-Protect comment="SYN Flood protect" disabled=yes  

ip firewall filter add chain=SYN-Protect protocol=tcp tcp-flags=syn limit=400,5 connection-state=new action=accept comment="" disabled=no 

ip firewall filter add chain=SYN-Protect protocol=tcp tcp-flags=syn connection-state=new  action=drop comment="" disabled=no 

For v6.x (version 6.X 이상에 적용)

ip settings set tcp-syncookies=yes

For older version. (6.X 이하에 적용)

ip firewall connection tracking set tcp-syncookie=yes

참고url : https://wiki.mikrotik.com/wiki/DoS_attack_protection

환경

우분투 16.04 LTS 

apt-get install keepalived

keepalived 설치

vi /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {

   notification_email {

   }

}

vrrp_instance xdnpass {

    state MASTER              # keepalived 시작시 MASTER로서 시작할지 BACKUP으로 시작할지를 지정

#    state BACKUP

    interface eth1             # VRRP패킷을 송신하거나 수실할 인터페이스를 지정

    virtual_router_id 100    # 가상 라우터 ID.VRRP 인스턴스 마다 고유한 값을 지정. 지정할 수 있는 범위는 0~255

    priority 101                # VRRP의 우선순위값. 마스터를 선출할 때 이 값이 큰 것이 우선

#    priority 100

    advert_int 2               # VRRP패킷 송신 간격. 초단위로 지정

    garp_master_delay 2    # 마스터 상태로 변경된 후에 gratuitous ARP를 재송신하기까지 대기시간을 초단위로 지정

    authentication {

        auth_type PASS

        auth_pass xdnroute

    }

    virtual_ipaddress {

        121.126.223.193    # virtual_ipaddress  VIP(가상주소). 형식은 다음과 같고 여러 개 지정할 수 있음.

   # <IPADDR>/<MASK>dev<STRIng>

    }

}

vrrp_instance private6pass {

    state MASTER

    interface eth0

    virtual_router_id 101

    priority 101

    advert_int 2

    garp_master_delay 2

    authentication {

        auth_type PASS

        auth_pass xdnroute

    }

    virtual_ipaddress {

        10.1.6.241

    }

}

## rsyslog 를 이용한 client log를 원격지 LOG 수집서버로 쌓기

1) LOG SERVER conf 수정

vi /etc/rsyslog.conf

# provides UDP syslog reception

$ModLoad imudp                            -  주석제거

$UDPServerRun 514                         -  주석제거

$template FILENAME,"/var/log/%hostname%/%$YEAR%_%$MONTH%_%$DAY%.log"        - 추가

*.* ?FILENAME                                                                                                   - 추가

/etc/init.d/rsyslog restart

2) client conf

vi /etc/rsyslog.conf

syslog

#*.*;auth,authpriv.none         -/var/log/syslog            - 주석, 복사

*.*;auth,authpriv.none          @172.16.1.1:514            - @LOG Server IP:514

messages

*.=info;*.=notice;*.=warn;\

        auth,authpriv.none;\

        cron,daemon.none;\

        mail,news.none          @172.16.1.1:514

/etc/init.d/rsyslog restart

LOG 수집 서버에 /var/log/호스트네임/날짜 로 로그 수집이 되는지 확인. 끝.

참고 url : http://idchowto.com/?p=16367

http://egloos.zum.com/outspace/v/3091255

** 환경

CentOS 7 x86_64

Cacti 1.1.38 

****   centos 7.0 부터 iptables 설정이 아주 이상해졌다.

아래 과정을 꼭 해주길 권장한다.

systemctl stop firewalld

systemctl disable firewalld

/etc/selinux  - disabled

/etc/iptables.sh  생성관리

###  apache 2.4 설치

# Install Apache 2.4

sudo yum install httpd -y

sudo sed -i 's/^/#&/g' /etc/httpd/conf.d/welcome.conf

sudo sed -i "s/Options Indexes FollowSymLinks/Options FollowSymLinks/" /etc/httpd/conf/httpd.conf

sudo systemctl start httpd.service

sudo systemctl enable httpd.service

###  MariaDB 10.2 설치

# Install MariaDB 10.2

curl -sS https://downloads.mariadb.com/MariaDB/mariadb_repo_setup | sudo bash

sudo yum install MariaDB-server MariaDB-client -y

sudo systemctl start mariadb.service

sudo systemctl enable mariadb.service

###  MariDB root password 설정

# Secure MariaDB 10.2

sudo /usr/bin/mysql_secure_installation

# When prompted, answer questions as below:

# - Enter current password for root (enter for none): Just press the Enter button

# - Set root password? [Y/n]: Y

# - New password: your-MariaDB-root-password

# - Re-enter new password: your-MariaDB-root-password

# - Remove anonymous users? [Y/n]: Y

# - Disallow root login remotely? [Y/n]: Y

# - Remove test database and access to it? [Y/n]: Y

# - Reload privilege tables now? [Y/n]: Y

# Create a MariaDB database for Cacti

mysql -u root -p

# For security purposes, be sure to replace "cacti", "cactiuser", and "yourpassword" with your own ones. 

CREATE DATABASE cacti;

CREATE USER 'cactiuser'@'localhost' IDENTIFIED BY 'yourpassword';

GRANT ALL PRIVILEGES ON cacti.* TO 'cactiuser'@'localhost' IDENTIFIED BY 'yourpassword' WITH GRANT OPTION;

FLUSH PRIVILEGES;

EXIT;

###   PHP7.1 설치

# Install required PHP 7.1 components for Cacti

sudo rpm -Uvh https://mirror.webtatic.com/yum/el7/webtatic-release.rpm

sudo yum install -y mod_php71w php71w-process php71w-common php71w-pdo php71w-xml php71w-ldap php71w-mbstring php71w-gd php71w-snmp php71w-mysqlnd php71w-cli php71w-mcrypt php71w-opcache php71w-imap php71w-intl

sudo cp /etc/php.ini /etc/php.ini.bak

sudo sed -i 's#;date.timezone =#date.timezone = America/Los_Angeles#' /etc/php.ini

###  CACTI 1.1.38 다운로드

wget https://www.cacti.net/downloads/cacti-1.1.38.tar.gz

cacti-1.1.38.tar.gz

tar zxvf cacti-1.1.38.tar.gz 

  mv /root/cacti-1.1.38 /opt/cacti

ln -s /opt/cacti-1.1.38 /var/www/html/cacti

touch /opt/cacti/log/cacti.log

 chown -R apache:apache /opt/cacti

###   CACTI SQL SB 추가

mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql -u root -p mysql

mysql -u root -p cacti < /var/www/html/cacti/cacti.sql

mysql -u root -p

# In the MySQL shell:

GRANT SELECT ON mysql.time_zone_name TO cactiuser@localhost IDENTIFIED BY 'yourpassword';

FLUSH PRIVILEGES;

EXIT;

###    cacti config.php 수정

vi /var/www/html/cacti/include/config.php

$database_type     = 'mysql';

$database_default  = 'cacti';

$database_hostname = 'localhost';

$database_username = 'cactiuser';

$database_password = 'yourpassword';

$database_port     = '3306';

$database_ssl      = false;

$url_path = '/cacti/';

###  crontab 추가

 crontab -u apache -e

*/5 * * * * php /var/www/html/cacti/poller.php > /dev/null 2>&1

cat <<EOF | sudo tee -a /etc/httpd/conf.d/cacti.conf

<VirtualHost *:80>

ServerAdmin admin@example.com

DocumentRoot /var/www/html/

ServerName cacti.example.com

ServerAlias www.cacti.example.com

<Directory /var/www/html/cacti/>

Options FollowSymLinks

AllowOverride All

Order allow,deny

allow from all

</Directory>

ErrorLog /var/log/httpd/cacti.example.com-error_log

CustomLog /var/log/httpd/cacti.example.com-access_log common

</VirtualHost>

EOF

systemctl restart httpd.service

###  my.cnf 수정

vi /etc/my.cnf

[client]

default-character-set=utf8mb4

[mysql]

default-character-set=utf8mb4

[mysqld]

collation-server=utf8mb4_unicode_ci

init-connect='SET NAMES utf8mb4'

character-set-server = utf8mb4

max_heap_table_size=256M

tmp_table_size=80M

join_buffer_size=80M

innodb_buffer_pool_size=963M

innodb_doublewrite=OFF

innodb_flush_log_at_timeout=3

innodb_read_io_threads=32

innodb_write_io_threads=16

systemctl restart mariadb.service

**  mariadb 재시작 시 error 가 발생하는 경우가 생긴다.

이 때 /var/lib/mysql/  

ib_logfile0

ib_logfile1

ibdata1

3개의 파일을 삭제 한 뒤 다시 시작하면 된다.

참고url

https://www.vultr.com/docs/how-to-install-cacti-1-1-on-centos-7

http://idchowto.com/?p=11107

* 환경

  - Ubuntu 16.04 LTS

  - Cacti 1.1.38.tar.gz

apt-get update

apt-get upgrade

## Mysql Server 설치

apt-get install mysql-server-5.7   (최신)

## php, apache2 설치

apt-get install php-xml php-ldap php-mbstring php-gd php-snmp php-gmp rrdtool snmp librrds-perl apache2

## Cacti 1.1.38 다운 (최신)

wget https://www.cacti.net/downloads/cacti-1.1.38.tar.gz

cacti-1.1.38.tar.gz

## cacti 압축 해제

tar zxvf cacti-1.1.38.tar.gz

mv cacti-1.1.38 /opt/cacti

## Log 경로 설정

mkdir /opt/logs

  touch /opt/logs/cacti.log

  touch /opt/logs/httpd_access.log

  touch /opt/logs/httpd_error.log

  chown -R www-data /opt/logs/*

## Mysql cacti DB 생성

mysqladmin --user=root --password create cacti

mysql --user root -p cacti < /opt/cacti/cacti.sql

 mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql -u root -p mysql

 mysql --user root --password mysql

###Enter your mysql root password.
###This will enter you into the mysql console for mysql database.
###NOTE: ‘somepassword’ referenced here is the cacti user password and must be the same as used in cacti configuration in the next section

mysql> GRANT ALL ON cacti.* TO cacti@localhost IDENTIFIED BY 'somepassword';
mysql> GRANT SELECT ON mysql.time_zone_name TO cacti@localhost IDENTIFIED BY 'somepassword';

Exit

## cacti config 수정

vi /opt/cacti/include/config.php 

### Find these variables and make the following changes

$database_type = 'mysql';
$database_default = 'cacti';
$database_hostname = 'localhost';
$database_username = 'cactiuser';
$database_password = somepassword;
$database_port = '3306';
$database_ssl = false;
$url_path = '';

##  file permissions 설정

chown -R www-data:www-data /opt/cacti/resource/snmp_queries

  chown -R www-data:www-data /opt/cacti/resource/script_server

  chown -R www-data:www-data /opt/cacti/resource/script_queries

  chown -R www-data:www-data /opt/cacti/scripts

  chown -R www-data:www-data /opt/cacti/rra/ /opt/cacti/log/

  chown -R www-data:www-data /opt/cacti/cache/mibcache

  chown -R www-data:www-data /opt/cacti/cache/realtime

  chown -R www-data:www-data /opt/cacti/cache/spikekill

##   Apache config

touch /etc/apache2/sites-available/cacti.conf

  vi /etc/apache2/sites-available/cacti.conf 

<VirtualHost *:80>

    <Location />
       require all granted
   </Location>

   ServerAdmin webmaster@localhost
   DocumentRoot /opt/cacti
   ErrorLog /opt/logs/httpd_error.log
   CustomLog /opt/logs/httpd_access.log combined

</VirtualHost>

  rm /etc/apache2/sites-enabled/*

  a2ensite cacti.conf

##   crontab 등록

vi /etc/crontab

###Add line at bottom

*/5 * * * * www-data php /opt/cacti/poller.php > /dev/null 2>&1

##  MySQL my.cnf 튜닝

vi /etc/mysql/mysql.conf.d/mysqld.cnf

###Add following lines to the bottom of the configuration file:

Max_heap_table_size = 256M
Tmp_table_size = 64M
Join_buffer_size = 64M
Innodb_doublewrite = OFF
Innodb_buffer_pool_size = 963M
Innodb_flush_log_at_timeout = 3
Innodb_read_io_threads = 32
Innodb_write_io_threads = 16

/etc/init.d/apache2 restart

/etc/init.d/mysql restart

*****  여기까지 했지만 cacti server IP 접근을 해도 500 error 만 나오고 정상적으로 열리지 않았다.

온갖 구글링을 해서 php7.0 버전이 너무 높아 호환성 에러가 나는 것을 찾았다.

apt-get install libapache2-mod-php

apt-get install php-curl

apt-get install php-mysql

추가 설치 후 정상 접속 가능

##    cacti 접속 후 기본 setup

http://[cacti server IP address]

default account 

admin  //  admin

참고 url

https://www.blackhillsinfosec.com/how-to-install-cacti-on-ubuntu/

https://www.phpschool.com/gnuboard4/bbs/board.php?bo_table=qna_function&wr_id=391359

https://github.com/spotweb/spotweb/issues/134

https://www.itzgeek.com/how-tos/linux/ubuntu-how-tos/setup-cacti-network-monitoring-tool-on-ubuntu-14-04-linux-mint-17.html

LG그램에서 터치패드 Fn+F5 가 죽어도 안된다.ㅠㅠㅠㅠ

이유를 여러가지 찾아봤는데, 보통의 터치패드는 시냅틱 터치패드라는 제품이 들어가 있어 웬만하면 지원 하지만,

이노무 LG그램은 Elantech Touchpad 뭐 암튼 이런거다...그래서 안되는거 같다.

안되면 되게 해야지....

방법을 찾다가

스크립트 만들어서 돌려버렸다.

vi /usr/local/sbin/toggleTouchpad

#!/bin/bash

tgid=`xinput list | grep Elantech | awk '{ print $6 }' | sed 's/id=//g'`

status=`xinput list-props ${tgid} | grep Device\ Enabled | sed -e 's/.*\:[ \t]\+//g'`

if [ 1 == $status ] ; then

xinput disable $tgid

else

xinput enable $tgid

fi

윈도우+F5 로 등록했다. 키보드 단축키 등록에 Fn키 등록이 되지 않아 쓸모 없는 윈도우키로 조합했다.

아주 잘되네...아휴 속 시원해