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Implement WordPress automatic Updates using wp-config file
Before editing, creating a complete backup.
After backup, Navigate to the home directory and makes changes in wp-config.php file.
cd /var/www/domain.com
nano wp-config.php
Add the following…
/** Enable Auto Updates */
define('WP_AUTO_UPDATE_CORE', true);
add_filter( 'auto_update_plugin', '__return_true' );
add_filter( 'auto_update_theme', '__return_true' );
what is the use of /etc/udev/rules.d/70-persistent-net.rules file in linux? is anyother way to change interface name in linux other than 70-persistent-net.rules?
This file associates your NIC’s MAC address with an interface name that will be given to the NIC at startup. There are certainly ways to change the name at runtime but if you reboot, it’s gonna be the contents of that file that count.
Additionally, you can use it for renaming the interfaces
MariaDB [(none)]> show table status from admin_geek01; +-----------------------------+--------+---------+------------+------+----------------+-------------+------------------+--------------+-----------+----------------+---------------------+---------------------+---------------------+-----------------+----------+----------------+---------+ | Name | Engine | Version | Row_format | Rows | Avg_row_length | Data_length | Max_data_length | Index_length | Data_free | Auto_increment | Create_time | Update_time | Check_time | Collation | Checksum | Create_options | Comment | +-----------------------------+--------+---------+------------+------+----------------+-------------+------------------+--------------+-----------+----------------+---------------------+---------------------+---------------------+-----------------+----------+----------------+---------+ | 2qGr3sjm_commentmeta | MyISAM | 10 | Dynamic | 0 | 0 | 2704 | 281474976710655 | 9216 | 2704 | 1073 | 2015-12-10 13:59:26 | 2015-12-30 22:51:44 | 2016-01-29 23:01:12 | utf8_general_ci | NULL | | | | 2qGr3sjm_comments | MyISAM | 10 | Dynamic | 0 | 0 | 8888 | 281474976710655 | 7168 | 8888 | 530 | 2015-12-10 13:59:26 | 2015-12-30 22:51:44 | 2016-01-29 12:35:32 | utf8_general_ci | NULL | | | | 2qGr3sjm_links | MyISAM | 10 | Dynamic | 0 | 0 | 0 | 281474976710655 | 1024 | 0 | 1 | 2015-12-10 13:59:26 | 2015-12-10 13:59:26 | 2015-12-10 13:59:26 | utf8_general_ci | NULL | | | | 2qGr3sjm_options | InnoDB | 10 | Compact | 167 | 6671 | 1114112 | 0 | 16384 | 6291456 | 18191 | 2015-12-10 13:59:26 | NULL | NULL | utf8_general_ci | NULL | | | | 2qGr3sjm_postmeta | MyISAM | 10 | Dynamic | 1758 | 106 | 187856 | 281474976710655 | 116736 | 0 | 7564 | 2015-12-10 13:59:26 | 2016-02-19 11:42:42 | 2016-02-07 11:40:30 | utf8_general_ci | NULL | | | | 2qGr3sjm_posts | InnoDB | 10 | Compact | 3547 | 1926 | 6832128 | 0 | 442368 | 6291456 | 2966 | 2015-12-10 13:59:26 | NULL | NULL | utf8_general_ci | NULL | | | | 2qGr3sjm_stb_styles | MyISAM | 10 | Dynamic | 7 | 845 | 5920 | 281474976710655 | 8192 | 0 | NULL | 2015-12-10 13:59:26 | 2015-12-10 13:59:26 | NULL | utf8_general_ci | NULL | | | | 2qGr3sjm_term_relationships | MyISAM | 10 | Fixed | 899 | 21 | 18900 | 5910974510923775 | 46080 | 21 | NULL | 2015-12-10 13:59:26 | 2016-02-19 11:36:09 | 2016-02-07 11:40:30 | utf8_general_ci | NULL | | | | 2qGr3sjm_term_taxonomy | MyISAM | 10 | Dynamic | 105 | 39 | 4148 | 281474976710655 | 9216 | 0 | 108 | 2015-12-10 13:59:26 | 2016-02-19 11:36:09 | 2016-02-07 11:40:29 | utf8_general_ci | NULL | | | | 2qGr3sjm_termmeta | InnoDB | 10 | Compact | 0 | 0 | 16384 | 0 | 32768 | 6291456 | 1 | 2015-12-10 13:59:26 | NULL | NULL | utf8_general_ci | NULL | | | | 2qGr3sjm_terms | MyISAM | 10 | Dynamic | 105 | 30 | 3176 | 281474976710655 | 13312 | 0 | 108 | 2015-12-10 13:59:26 | 2015-12-10 13:59:26 | 2015-12-10 13:59:26 | utf8_general_ci | NULL | | | | 2qGr3sjm_usermeta | InnoDB | 10 | Compact | 37 | 442 | 16384 | 0 | 32768 | 6291456 | 41 | 2015-12-10 13:59:26 | NULL | NULL | utf8_general_ci | NULL | | | | 2qGr3sjm_users | MyISAM | 10 | Dynamic | 1 | 120 | 120 | 281474976710655 | 4096 | 0 | 2 | 2015-12-10 13:59:26 | 2015-12-10 13:59:26 | 2015-12-10 13:59:26 | utf8_general_ci | NULL | | | +-----------------------------+--------+---------+------------+------+----------------+-------------+------------------+--------------+-----------+----------------+---------------------+---------------------+---------------------+-----------------+----------+----------------+---------+
Check services that are enabled on CentOS 7
# systemctl list-unit-files
Or for a specific service
# systemctl status mysqld
Disabling a service on boot in CentOS 7
To disable, it’s simply a matter of running systemctl disable on the desired service.
# systemctl disable mysqld
Check which services failed to start on boot on CentOS 7
As a bonus, systemctl allows you to list all services that failed to start on boot, even though they were configured to start on boot.
# systemctl --failed
There are a few reasons to install a cron job to create full database dumps versus copying the /var/lib/mysql data. The MySQL service may have a lock on the database file(s) when it attempts to replicate the data file, causing it to fail; if the backup on the data files does succeed, the InnoDB log files may not match with the ibdata increasing the chance of full corruption or lost data; MyISAM data and table structures can face similar issues.
Plesk
Create a location for the dumps. This will be the folder the dumps are exported to by the script.
# mkdir -pv /usr/local/db/dumps
Create a script that cron can execute. Create /usr/local/bin/dbdump with these contents:
nano /usr/local/bin/dbdump
Put this in the file (for Plesk)
#!/bin/bash for db in $(mysql -uadmin -p`cat /etc/psa/.psa.shadow` -e 'show databases' -s --skip-column-names); do echo -n "dumping $db..."; mysqldump -uadmin -p`cat /etc/psa/.psa.shadow` $db > "/usr/local/db/dumps/$db.sql"; echo "[done]"; done
Make it executable:
# chmod +x /usr/local/bin/dbdump
For non plesk:
# nano /usr/local/bin/dbdump
Put this in the file
for db in $(mysql -uroot -pPASSWORD -e 'show databases' -s --skip-column-names); do echo -n "dumping $db..."; mysqldump -uroot -pPASSWORD $db > "/usr/local/db/dumps/$db.sql"; echo "[done]"; done
Make it executable:
# chmod +x /usr/local/bin/dbdump
Create /etc/cron.d/dbdump with these contents:
# nano /etc/cron.d/dbdump
# Cronjob to dump databases nightly 05 0 * * * root /usr/local/bin/dbdump >/dev/null 2>&1
Link to install zabbix server on centOS 6- http://www.unixmen.com/install-zabbix-monitoring-tool-centos-6-5/
Zabbix Documentation – https://www.zabbix.com/documentation/3.4/manual/installation/install_from_packages/rhel_centos
Install on CentOS 7 – http://www.unixmen.com/how-to-install-zabbix-server-on-centos-7/
Install Epel
# yum install epel-release
Configure the ZabbixZone package repository and GPG key using command:
# rpm --import http://repo.zabbix.com/RPM-GPG-KEY-ZABBIX
# rpm -Uv http://repo.zabbix.com/zabbix/2.4/rhel/7/x86_64/zabbix-release-2.4-1.el7.noarch.rpm
Install the agent
# yum install zabbix-agent
Modify Zabbix Agent Configuration
Open zabbix_agentd.conf and make below necessary changes (Add your Zabbix Server IP and add Zabbix Agent hostname) and save + Exit.
# sudo nano /etc/zabbix/zabbix_agentd.conf Server=192.168.1.106 ServerActive=192.168.1.106 Hostname=server.geekdecoder.com
Set to on
# chkconfig zabbix-agent on
Restart Zabbix Agent
# service zabbix-agent restart or # /etc/init.d/zabbix-agent restart # For Systemd Systeme # # systemctl restart zabbix-agent.service or # systemctl restart zabbix-agent or # /bin/systemctl restart zabbix-agent.service
Add firewall rule in CentOS 7:
# firewall-cmd --permanent --zone=public --add-port=10050/tcp success # firewall-cmd --reload success
Zip and exclude one directory
Change to the directory…
# cd /var/www/vhosts/domainname/httpdocs/
# zip -r domainname.zip * -x \*test\*
2 directories
# zip -r domainname.zip * -x \*test\* \*test2\*
The ‘neighbor table overflow’ is a VERY common linux issue on large networks. Some network trigger this with default linux settings (because the previous network regime put so many IP address subnets on a single vlan , it creates large ARP tables – which is not normal / default settings). It is not an indication of anything wrong. It is a trigger of linux default.
Here is how to adjust:
If you see this….
__ratelimit: 20 callbacks suppressed Neighbour table overflow.
For busy networks increase the kernel’s internal ARP cache size. The following kernel variables are used:
net.ipv4.neigh.default.gc_thresh1 net.ipv4.neigh.default.gc_thresh2 net.ipv4.neigh.default.gc_thresh3 To see current values, type:
Run this…
# sysctl net.ipv4.neigh.default.gc_thresh1 net.ipv4.neigh.default.gc_thresh1 = 128
# sysctl net.ipv4.neigh.default.gc_thresh2 net.ipv4.neigh.default.gc_thresh2 = 512
# sysctl net.ipv4.neigh.default.gc_thresh3 net.ipv4.neigh.default.gc_thresh3 = 1024
You need to make sure that the arp table to become bigger than the above defaults. The above limitations are good for small network or a single server. This will also affect your DNS traffic.
How Do I Fix “Neighbour Table Overflow” Error?
# vi /etc/sysctl.conf
Append the following:
## works best with <= 500 client computers ## # Force gc to clean-up quickly net.ipv4.neigh.default.gc_interval = 3600 # Set ARP cache entry timeout net.ipv4.neigh.default.gc_stale_time = 3600 # Setup DNS threshold for arp net.ipv4.neigh.default.gc_thresh3 = 4096 net.ipv4.neigh.default.gc_thresh2 = 2048 net.ipv4.neigh.default.gc_thresh1 = 1024 [/bash] To load new changes type the following command:[bash] # sysctl -p [/bash]
Install MySQL / MariaDB
Installing MariaDB is as simple as running just one command:
# yum -y install mariadb-server mariadb
And then start MySQL, now MariaDB:
# systemctl start mariadb
Be sure that MySQL/MariaDB starts at boot:
# systemctl enable mariadb
To check the status of MySQL/MariaDB:
# systemctl status mariadb
To top MySQL/MariaDB:
# systemctl stop mariadb
Check the installation with the command client:
# mysql