Linux Conquering Cloud

Monday, April 1, 2013

Mysql

To login (from unix shell) use -h only if needed.

# [mysql dir]/bin/mysql -h hostname -u root -p

Create a database on the sql server.

mysql> create database [databasename];

List all databases on the sql server.

mysql> show databases;

Switch to a database.

mysql> use [db name];

To see all the tables in the db.

mysql> show tables;

To see database’s field formats.

mysql> describe [table name];

To delete a db.

mysql> drop database [database name];

To delete a table.

mysql> drop table [table name];

Show all data in a table.

mysql> SELECT * FROM [table name];

Returns the columns and column information pertaining to the designated table.

mysql> show columns from [table name];

Show certain selected rows with the value “whatever”.

mysql> SELECT * FROM [table name] WHERE [field name] = “whatever”;

Show all records containing the name “Bob” AND the phone number ’3444444′.

mysql> SELECT * FROM [table name] WHERE name = “Bob” AND phone_number = ’3444444′;

Show all records not containing the name “Bob” AND the phone number ’3444444′ order by the phone_number field.

mysql> SELECT * FROM [table name] WHERE name != “Bob” AND phone_number = ’3444444′ order by phone_number;

Show all records starting with the letters ‘bob’ AND the phone number ’3444444′.

mysql> SELECT * FROM [table name] WHERE name like “Bob%” AND phone_number = ’3444444′;

Show all records starting with the letters ‘bob’ AND the phone number ’3444444′ limit to records 1 through 5.

mysql> SELECT * FROM [table name] WHERE name like “Bob%” AND phone_number = ’3444444′ limit 1,5;

Use a regular expression to find records. Use “REGEXP BINARY” to force case-sensitivity. This finds any record beginning with a.

mysql> SELECT * FROM [table name] WHERE rec RLIKE “^a”;

Show unique records.

mysql> SELECT DISTINCT [column name] FROM [table name];

Show selected records sorted in an ascending (asc) or descending (desc).

mysql> SELECT [col1],[col2] FROM [table name] ORDER BY [col2] DESC;

Return number of rows.

mysql> SELECT COUNT(*) FROM [table name];

Sum column.

mysql> SELECT SUM(*) FROM [table name];

Join tables on common columns.

mysql> select lookup.illustrationid, lookup.personid,person.birthday from lookup left join person on lookup.personid=person.personid=statement to join birthday in person table with primary illustration id;

Creating a new user. Login as root. Switch to the MySQL db. Make the user. Update privs.

# mysql -u root -p
mysql> use mysql;
mysql> INSERT INTO user (Host,User,Password) VALUES(‘%’,'username’,PASSWORD(‘password’));
mysql> flush privileges;

Change a users password from unix shell.

# [mysql dir]/bin/mysqladmin -u username -h hostname.blah.org -p password ‘new-password’

Change a users password from MySQL prompt. Login as root. Set the password. Update privs.

# mysql -u root -p
mysql> SET PASSWORD FOR ‘user’@'hostname’ = PASSWORD(‘passwordhere’);
mysql> flush privileges;

Recover a MySQL root password. Stop the MySQL server process. Start again with no grant tables. Login to MySQL as root. Set new password. Exit MySQL and restart MySQL server.

# /etc/init.d/mysql stop
# mysqld_safe –skip-grant-tables &
# mysql -u root
mysql> use mysql;
mysql> update user set password=PASSWORD(“newrootpassword”) where User=’root’;
mysql> flush privileges;
mysql> quit
# /etc/init.d/mysql stop
# /etc/init.d/mysql start

Set a root password if there is on root password.

# mysqladmin -u root password newpassword

Update a root password.

# mysqladmin -u root -p oldpassword newpassword

Allow the user “bob” to connect to the server from localhost using the password “passwd”. Login as root. Switch to the MySQL db. Give privs.
Update privs.

# mysql -u root -p
mysql> use mysql;
mysql> grant usage on *.* to bob@localhost identified by ‘passwd’;
mysql> flush privileges;

Give user privilages for a db. Login as root. Switch to the MySQL db. Grant privs. Update privs.

# mysql -u root -p
mysql> use mysql;
mysql> INSERT INTO db (Host,Db,User,Select_priv,Insert_priv,Update_priv,Delete_priv,Create_priv,Drop_priv) VALUES (‘%’,'databasename’,'username’,'Y’,'Y’,'Y’,'Y’,'Y’,'N’);
mysql> flush privileges;

or

mysql> grant all privileges on databasename.* to username@localhost;
mysql> flush privileges;

To update info already in a table.

mysql> UPDATE [table name] SET Select_priv = ‘Y’,Insert_priv = ‘Y’,Update_priv = ‘Y’ where [field name] = ‘user’;

Delete a row(s) from a table.

mysql> DELETE from [table name] where [field name] = ‘whatever’;

Update database permissions/privilages.

mysql> flush privileges;

Delete a column.

mysql> alter table [table name] drop column [column name];

Add a new column to db.

mysql> alter table [table name] add column [new column name] varchar (20);

Change column name.

mysql> alter table [table name] change [old column name] [new column name] varchar (50);

Make a unique column so you get no dupelicates.

mysql> alter table [table name] add unique ([column name]);

Make a column bigger.

mysql> alter table [table name] modify [column name] VARCHAR(3);

Delete unique from table.

mysql> alter table [table name] drop index [colmn name];

Load a CSV file into a table.

mysql> LOAD DATA INFILE ‘/tmp/filename.csv’ replace INTO TABLE [table name] FIELDS TERMINATED BY ‘,’ LINES TERMINATED BY ‘\n’ (field1,field2,field3);

Dump all databases for backup. Backup file is sql commands to recreate all db’s.

# [mysql dir]/bin/mysqldump -u root -ppassword –opt >/tmp/alldatabases.sql

Dump one database for backup.

# [mysql dir]/bin/mysqldump -u username -ppassword –databases databasename >/tmp/databasename.sql

Dump a table from a database.

# [mysql dir]/bin/mysqldump -c -u username -ppassword databasename tablename > /tmp/databasename.tablename.sql

Restore database (or database table) from backup.

# [mysql dir]/bin/mysql -u username -ppassword databasename < /tmp/databasename.sql

Create Table Example 1.

mysql> CREATE TABLE [table name] (firstname VARCHAR(20), middleinitial VARCHAR(3), lastname VARCHAR(35),suffix VARCHAR(3),officeid VARCHAR(10),userid VARCHAR(15),username VARCHAR(8),email VARCHAR(35),phone VARCHAR(25), groups VARCHAR(15),datestamp DATE,timestamp time,pgpemail VARCHAR(255));

Create Table Example 2.

mysql> create table [table name] (personid int(50) not null auto_increment primary key,firstname varchar(35),middlename varchar(50),lastnamevarchar(50) default ‘bato’);

Help and Show Commands

$ mysql –help | less
$ mysqld –help
$ mysqlshow –help | less
$ mysqldump –help | less
$ mysqlshow – show all databases.
$ mysqlshow db_name – all tables in particular database.
$ mysqlshow db_name BA* – all tables which start from BA letters.mysql> \?
mysql> use db_name;
mysql> show databases;
mysql> show databases like ‘ba%’
mysql> show tables;
mysql> describe table_name;
mysql> select user(), now(), version(), database();
+—————+———————+—————-+————+
| user() | now() | version() | database() |
+—————+———————+—————-+————+
| ana@localhost | 2003-01-05 21:24:27 | 4.0.1-alpha-nt | test |
+—————+———————+—————-+————+mysql> show tables from db_name
mysql> show tables from db_name like ‘__ab%’
mysql> show columns from table_name
mysql> show columns from table_name from db_name
mysql> show grants for user_name
mysql> show index from table_name
mysql> show index from table_name from db_name
mysql> show processlist
mysql> show status
mysql> show table status from db_name
mysql> show variables

Php --SourceGuardian

PHP script /home/adzworkc/ClixScript_PHP_DOCS/classes/class.vars.php is protected by SourceGuardian and requires the SourceGuardian loader ixed.5.3.lin. The SourceGuardian loader has not been installed, or is not installed correctly. Please find the required loader within SourceGuardian installation directory or visit the SourceGuardian php encoder site to download it.

root@server [~]# /scripts/phpextensionmgr list
Available Extensions:
EAccelerator
IonCubeLoader
Zendopt
Xcache
SourceGuardian
PHPSuHosin

root@server [~]# /scripts/phpextensionmgr install SourceGuardian

===

If the issue still persist
check the php.ini

root@server [/home]# php -i | grep ini

We can see

===

Configuration File (php.ini) Path => /usr/local/lib
Loaded Configuration File => /usr/local/lib/php.ini
Scan this dir for additional .ini files => (none)
additional .ini files parsed => (none)

===

Now open

root@server [/home]# vi /usr/local/lib/php.ini

and check the extention file

===
root@server [/home]# cd /usr/local/lib/php/extensions/no-debug-non-zts-20060613

root@server [/usr/local/lib/php/extensions/no-debug-non-zts-20060613]# ll

drwxr-xr-x 2 root root 4096 Jan 21 20:51 ./
drwxr-xr-x. 4 root root 4096 Dec 29 12:05 ../
-rw-r–r– 1 root root 79448 Jan 21 20:50 ixed.5.2.lin
-rwxr-xr-x 1 root root 544910 Jan 4 19:03 pdo.a*
-rwxr-xr-x 1 root root 275820 Jan 4 19:03 pdo_mysql.a*

===

Now we can see that the version is ixed.5.2.lin but we need ixed.5.3.lin.

So downlaod file from

http://www.sourceguardian.com/loaders.html

and upload it to this folder
root@server [/usr/local/lib/php/extensions/no-debug-non-zts-20060613]#

Then open

vi /usr/local/lib/php.ini
shift +g
we can sse that

===

extension=”ixed.5.2.lin”
zend_extension=”/usr/local/Zend/lib/Optimizer-3.3.9/php-5.2.x/ZendOptimizer.so”

===

Change the version here manually.

Modifying your PHP Handler Configuration

What’s my current configuration?

# /usr/local/cpanel/bin/rebuild_phpconf --current
Available handlers: suphp dso cgi none
DEFAULT PHP: 5
PHP4 SAPI: none
PHP5 SAPI: suphp
SUEXEC: enabled

Let’s say I wanted to switch to DSO, keeping PHP4 disabled, and SuExec enabled:
# /usr/local/cpanel/bin/rebuild_phpconf 5 none fcgi 1

For reference, the usage details:

Usage: /usr/local/cpanel/bin/rebuild_phpconf [--dryrun] [--no-restart] [--no-htaccess] [--current|--available]
--dryrun : Only display the changes that would be made
--no-restart : Don't restart Apache after updating the php.conf link
--no-htaccess : Don't update user configurable PHP mime mapping.
--current : Show current settings
--available : Show available handlers and PHP SAPIs
: Version of PHP to set as default handler for .php files
<php# handler="">: Type of Apache module to use in serving PHP requests
: enabled, disabled, 1 or 0

Fatal error: Allowed memory size of xxxxxxxx bytes exhausted If deactivating plugins doesn’t work try one of these methods for increasing the amount of memory a PHP script may consume

1. If you have access to your PHP.ini file, change the line in PHP.ini
If your line shows 32M try 64M:
memory_limit = 64M ; Maximum amount of memory a script may consume (64MB)

2. If you don’t have access to PHP.ini try adding this to an .htaccess file:
php_value memory_limit 64M

3. Try adding this line to your wp-config.php file:
Increasing memory allocated to PHP
define(‘WP_MEMORY_LIMIT’, ’64M’);

How to clear eximstats db

If the size of your eximstats database is getting large, you can do the following steps to clear it.

Login to mysql

mysql

mysql> use eximstats
mysql> delete from sends;
mysql> delete from smtp;
mysql> delete from failures;
mysql> delete from defers;

Load due to a particular domain in the server

Whenever the load in the server increases due to a particular user in the server. Check the following:

Find the domain owned by the user:

grep username /etc/userdomains

use the following command after you get the domain name:

less /usr/local/apache/domlogs/domain.com | awk ‘{print $1}’ | sort | uniq -c | sort -n

This will give the ip and number of connections in the descending order. For example:

 13832 65.52.110.145
 19112 66.249.68.183
208262 157.55.16.55

In the above case we can see too many connections from those ips. This is surely abnormal. Immediately block such ips in the server using csf

csf -d IP

[if not present use iptables].

SAMPLE PHP SCRIPT FOR SENDING MAILS

<?php

$Subject=”Trying to send”;
$Sender=”testing@betsexperts.com”;
$SendTo=”testmail4us@gmail.com”;
$Message2=”Testing mail”;

if(mail($SendTo, $Subject, $Message2, “From: $Sender”)){
print” Sent to: $SendTo … Sender: $Sender”;
}else{
print” Not sent to: $SendTo … Sender: $Sender”;
}

?>

Tips to remember:

Step 1:
Create a test.php inside public_html folder
For example —> /home/public_html/test.php
Step2:
Copy the above script and paste inside test.php (remember to change the ownership of test.php)
Step3:
run the url
For example—> if you are creating test.php in your website http://example.com
Run the url as http://example.com/test.php
The mail will automatically send as php

Pages

Monday, April 1, 2013