When the value is 1 (the default), the log buffer is written out to the log file at each transaction commit and the flush to disk operation is performed on the log file

Solution: Set the value is 2, the log buffer is written out to the file at each commit, but the flush to disk operation is not performed on it. However, the flushing on the log file takes place once per second also when the value is 2.

innodb_flush_log_at_trx_commit = 1

Hope this helps..
 

MySql User  on the HOST has a limit of only 4096 files to store by default. this has to be increased  to a certain number, otherwise  MySql database will be shutdown or corrupt due to insufficient files on the host.

To overcome this situation, you need to increase the file limit on the host.  Please add the below code in bash file and run it from your host as root, this will increase to the no.of files you need, but please make sure not to give the number above OS limit . the below example will allow 30,000 files for mysql user while creating any table partitions.

**********************************************

#! /bin/csh

cat >/etc/security/limits.d/mysql.conf <<EOF
mysql soft nofile 30000
mysql hard nofile 30000
EOF

**********************************************

To test the above scritp. login as user mysql and run “ulimit -n” command.

before running the script
> ulimit -n
4096

After running the above script
> ulimit -n
30000

it is worth a try…

First Try to Find the Line No’s of the Starting Date of 1 week (lets say 9 Apr 2010 – 16 Apr 2010)

grep -n ‘Time: 100409′ /var/log/mysqld/myserver_slow_queries.log | more

Copy or write down the Line no. let’s say 2399098

grep -n ‘Time: 100416′ /var/log/mysqld/myserver_slow_queries.log | more

Copy or write down the Last Line no. 2483712

now run the SED Unix Command to grab the data from start line to end line into a new log file.

sed -n 2399098,2483712p myserver_slow_queries.log > myserver_slow_queries.log.week

Done. One Week of Data from a Big Log file will be copied to a new file.

[Tue Jun 01 16:07:10 2010] [error] [client 100.100.11.12] 

DBI connect('host:database:port;mysql_connect_timeout=10','web',...)

failed: Host 'mysite.net' is blocked because of many connection errors;

unblock with 'mysqladmin flush-hosts' at [Tue Jun 01 16:07:10 2010]

[error] [client 100.100.21.211]

 

Solution:

FLUSH HOSTS will Free all the connection errors from buffer.

Cannot open your terminal ‘/dev/pts/7′ – please check

1) Exit out of the user First.

2) cd /dev/pts/7

3) chmod +0666 /dev/pts/7

4) then sudo su user

5) type Screen. then it’ll work.

Please let me know if this doesn’t work..

Relay_Log_Pos: 3630
Relay_Master_Log_File: MASTERMYSQL01-bin.000009
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 4
Relay_Log_Space: 3630
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 1519187

1 row in set (0.00 sec)

Above highlighted rows must be indicate related log files and  Slave_IO_Running and   Slave_SQL_Running: must be to YES.

Step 6:

On master 1:

mysql> show master status;
+————————+———-+————–+——————+
| File                   | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+————————+———-+————–+——————+
|MysqlMYSQL01-bin.000008 |      410 | adam         |                  |
+————————+———-+————–+——————+
1 row in set (0.00 sec)

The above scenario is for master-slave, now we will create a slave master scenario for the same systems and it will work as master master.

Step 7:

On Master2/Slave 1, edit my.cnf and master entries into it:

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
# Default to using old password format for compatibility with mysql 3.x
# clients (those using the mysqlclient10 compatibility package).
old_passwords=1
server-id=2

master-host = 192.168.16.4
master-user = replication
master-password = slave
master-port = 3306

log-bin                     #information for becoming master added
binlog-do-db=adam

[mysql.server]
user=mysql
basedir=/var/lib

[mysqld_safe]
err-log=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

Step 8:

Create a replication slave account on master2 for master1:

mysql> grant replication slave on *.* to ‘replication’@192.168.16.4 identified by ‘slave2′;

Step 9:

Edit my.cnf on master1 for information of its master.

[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock

# Default to using old password format for compatibility with mysql 3.x
# clients (those using the mysqlclient10 compatibility package).
old_passwords=1

log-bin
binlog-do-db=adam
binlog-ignore-db=mysql
binlog-ignore-db=test

server-id=1
#information for becoming slave.
master-host = 192.168.16.5
master-user = replication
master-password = slave2
master-port = 3306

[mysql.server]user=mysqlbasedir=/var/lib

[mysqld_safe]
err-log=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid

Step 10:

Restart both mysql master1 and master2.

On mysql master1:

mysql> start slave;

On mysql master2:

mysql > show master status;

On mysql master 1:

mysql> show slave status\G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.16.5
Master_User: replica
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: Mysql1MYSQL02-bin.000008
Read_Master_Log_Pos: 410
Relay_Log_File: Mysql1MYSQL01-relay-bin.000008
Relay_Log_Pos: 445
Relay_Master_Log_File: Mysql1MYSQL02-bin.000008
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 410
Relay_Log_Space: 445
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 103799
1 row in set (0.00 sec)

ERROR:
No query specified

Check for the hightlighted rows, make sure its running. Now you can create tables in the database and you will see changes in slave. Enjoy!!

[client]

[mysqld_safe]

[mysqld]

[mysql]

[isamchk]

This is one of the Best Configuration file from MYSQL

ADMINISTRATION BIBLE BOOK.

The configuration file supports options for multiple programs. Each program has its own directive,
which is a keyword in square brackets, such as [mysqld] or [client]. Here is a sample
configuration file from a production system:
# The following options will be passed to all MySQL clients
[client]
port = 3306
socket = /var/lib/mysql/mysql.sock
[mysqld]
#this will prevent mysql from starting
port = 3306
socket = /var/lib/mysql/mysql.sock
datadir =/var/lib/mysql
log_slow_queries = /var/log/mysql/mysqld_slow-queries.log
long_query_time = 4
max_connections=200
max_connect_errors = 400
wait_timeout=7200
connect_timeout=10
key_buffer = 512M
tmp_table_size = 32M
max_heap_table_size = 32M
max_allowed_packet = 32M
table_cache = 1800
join_buffer_size = 8M
sort_buffer_size = 16M
read_buffer_size = 8M
read_rnd_buffer_size = 524288
myisam_sort_buffer_size = 256M
thread_cache_size = 384
bulk_insert_buffer_size = 8M
query_cache_limit = 4M
query_cache_size = 128M
query_cache_type = 1
362
MySQL Server Tuning 10
query_prealloc_size = 65536
query_alloc_block_size = 131072
# Try number of CPU’s*2 for thread_concurrency
thread_concurrency = 4
#innodb configuration
innodb_data_home_dir = /mysql/data
innodb_data_file_path=ibdata1:200M:autoextend
innodb_log_group_home_dir = /mysql/data/data
innodb_log_arch_dir = /mysql/data/data
innodb_buffer_pool_size = 24576M
innodb_additional_mem_pool_size = 32M
innodb_log_file_size = 1024M
innodb_log_files_in_group = 2
innodb_log_buffer_size = 16M
innodb_flush_log_at_trx_commit = 1
innodb_lock_wait_timeout = 120
sync-binlog = 1
innodb_support_xa = 0
innodb_thread_concurrency = 128
innodb_file_per_table
# binary logging is required for replication
log-bin=mysql-bin
max_binlog_size = 1024M
server-id = 4
slave-skip-errors = 1062
expire-logs-days = 7
[mysqldump]
quick
max_allowed_packet = 16M
[mysql.server]
user=mysql
group=mysql
basedir=/var/lib
[mysqld_safe]
nice = -5
open_files_limit = 8192
log-error=/var/log/mysql/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
The configuration file supports options for multiple programs. Each program has its own directive,which is a keyword in square brackets, such as [mysqld] or [client]. Here is a sampleconfiguration file from a production system:# The following options will be passed to all MySQL clients[client]port = 3306socket = /var/lib/mysql/mysql.sock[mysqld]#this will prevent mysql from startingport = 3306socket = /var/lib/mysql/mysql.sockdatadir =/var/lib/mysqllog_slow_queries = /var/log/mysql/mysqld_slow-queries.loglong_query_time = 4max_connections=200max_connect_errors = 400wait_timeout=7200connect_timeout=10key_buffer = 512Mtmp_table_size = 32Mmax_heap_table_size = 32Mmax_allowed_packet = 32Mtable_cache = 1800join_buffer_size = 8Msort_buffer_size = 16Mread_buffer_size = 8Mread_rnd_buffer_size = 524288myisam_sort_buffer_size = 256Mthread_cache_size = 384bulk_insert_buffer_size = 8Mquery_cache_limit = 4Mquery_cache_size = 128Mquery_cache_type = 1362MySQL Server Tuning 10query_prealloc_size = 65536query_alloc_block_size = 131072# Try number of CPU’s*2 for thread_concurrencythread_concurrency = 4#innodb configurationinnodb_data_home_dir = /mysql/datainnodb_data_file_path=ibdata1:200M:autoextendinnodb_log_group_home_dir = /mysql/data/datainnodb_log_arch_dir = /mysql/data/datainnodb_buffer_pool_size = 24576Minnodb_additional_mem_pool_size = 32Minnodb_log_file_size = 1024Minnodb_log_files_in_group = 2innodb_log_buffer_size = 16Minnodb_flush_log_at_trx_commit = 1innodb_lock_wait_timeout = 120sync-binlog = 1innodb_support_xa = 0innodb_thread_concurrency = 128innodb_file_per_table# binary logging is required for replicationlog-bin=mysql-binmax_binlog_size = 1024Mserver-id = 4slave-skip-errors = 1062expire-logs-days = 7[mysqldump]quickmax_allowed_packet = 16M[mysql.server]user=mysqlgroup=mysqlbasedir=/var/lib[mysqld_safe]nice = -5open_files_limit = 8192log-error=/var/log/mysql/mysqld.logpid-file=/var/run/mysqld/mysqld.pid

The symptom

Suppose you call SHOW INNODB STATUS or another InnoDB-specific command and MySQL reports the following error:

“ERROR 1235 (42000): Cannot call SHOW INNODB STATUS because skip-innodb is defined”

Yet you search the MySQL configuration files and find that’s not true. And you know you have InnoDB tables, too. What’s going on?

As it turns out, the error message is a bit misleading. Many problems will cause this error message.

Dig deeper

If InnoDB says it’s disabled, it probably is. Look at a couple other things. Does SHOW ENGINES report InnoDB is disabled? How about SHOW VARIABLES LIKE 'have_innodb'? Try SHOW TABLE STATUS on an InnoDB table — are most columns NULL?

If so, you most likely have an InnoDB configuration error. Not that you’ve disabled it with skip-innodb, but there’s something wrong. If so, MySQL will still start, but the InnoDB storage engine, and tables that use it, will be disabled.

One possible solution

When this happened to me, it was a config file upgrade that I didn’t check carefully. The old directive for the InnoDB data file was as follows:

innodb_data_file_path           = ibdata1:10M:autoextend

When I upgraded the file, I changed it to

innodb_data_file_path = ibdata1:10M:autoextend:max:128M

That wouldn’t have been a problem, except the file was already larger than 128MB. This is a slightly hard error to catch sometimes, because it may not show up in your MySQL error log (it doesn’t on my Ubuntu laptop when I deliberately force the error to happen).

A note of general caution

For those of you who are new to InnoDB configuration and administration, be careful. InnoDB has to be told exactly what to do. If you do anything wrong, such as set the permissions wrong on InnoDB’s log or data files or directories, change the file sizes, or any of a bunch of other mistakes, it will be very unforgiving. It may even wipe your existing log and data files and replace them with new ones full of zeroes (yes, this will delete all your data).

The MySQL error log is your friend, but in many cases InnoDB doesn’t flush any output to it for a long time, so you might for example start MySQL and see “MySQL NOT started.” It might just be that InnoDB wasn’t shut down nicely and has to roll back transactions to get to a consistent state. If so, that information will show up in the log files, but it might take a Very Long Time.

If you need help

You can get help on the #mysql IRC channel, mailing lists, or just read the MySQL manual. I like the IRC channel best myself. It’s friendly and there are a lot of smart people there to answer your questions.

datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
skip-innodb    # (if you don’t want to use INNODB Tables)
max_connections = 500
key_buffer = 16M
myisam_sort_buffer_size = 64M
join_buffer_size = 1M
read_buffer_size = 1M
sort_buffer_size = 2M
table_cache = 1024
thread_cache_size = 64
wait_timeout = 1800
connect_timeout = 10
max_allowed_packet = 16M
max_connect_errors = 10
query_cache_limit = 1M
query_cache_size = 32M
query_cache_type = 1

[mysqld_safe]

err-log=/var/log/mysqld.log
open_files_limit = 8192

[mysqldump]

quick
max_allowed_packet = 16M

[myisamchk]

key_buffer = 64M

sort_buffer = 64M

read_buffer = 16M

write_buffer = 16M

[mysql.server]

user=mysql

How is the asynchronous query executed? Lets take a look at the figure below.

Version 1.1
Author: Falko Timme <ft [at] falkotimme [dot] com>
Last edited: 01/14/2006

This tutorial describes how to set up database replication in MySQL. MySQL replication allows you to have an exact copy of a database from a master server on another server (slave), and all updates to the database on the master server are immediately replicated to the database on the slave server so that both databases are in sync. This is not a backup policy because an accidentally issued DELETE command will also be carried out on the slave; but replication can help protect against hardware failures though.

In this tutorial I will show how to replicate the database exampledb from the master with the IP address 192.168.0.100 to a slave. Both systems (master and slave) are running Debian Sarge; however, the configuration should apply to almost all distributions with little or no modification.

Both systems have MySQL installed, and the database exampledb with tables and data is already existing on the master, but not on the slave.

I want to say first that this is not the only way of setting up such a system. There are many ways of achieving this goal but this is the way I take. I do not issue any guarantee that this will work for you!

1 Configure The Master

First we have to edit /etc/mysql/my.cnf. We have to enable networking for MySQL, and MySQL should listen on all IP addresses, therefore we comment out these lines (if existant):

#skip-networking
#bind-address            = 127.0.0.1

Furthermore we have to tell MySQL for which database it should write logs (these logs are used by the slave to see what has changed on the master), which log file it should use, and we have to specify that this MySQL server is the master. We want to replicate the database exampledb, so we put the following lines into /etc/mysql/my.cnf:

log-bin = /var/log/mysql/mysql-bin.log
binlog-do-db=exampledb
server-id=1

Then we restart MySQL:

/etc/init.d/mysql restart

Then we log into the MySQL database as root and create a user with replication privileges:

mysql -u root -p
Enter password:

Now we are on the MySQL shell.

GRANT REPLICATION SLAVE ON *.* TO ‘slave_user’@'%’ IDENTIFIED BY ‘<some_password>’; (Replace <some_password> with a real password!)
FLUSH PRIVILEGES;

Next (still on the MySQL shell) do this:

USE exampledb;
FLUSH TABLES WITH READ LOCK;
SHOW MASTER STATUS;

The last command will show something like this:

+---------------+----------+--------------+------------------+
| File          | Position | Binlog_do_db | Binlog_ignore_db |
+---------------+----------+--------------+------------------+
| mysql-bin.006 | 183      | exampledb    |                  |
+---------------+----------+--------------+------------------+
1 row in set (0.00 sec)

Write down this information, we will need it later on the slave!

Then leave the MySQL shell:

quit;

If you want to follow the first method, then do this:

mysqldump -u root -p<password> –opt exampledb > exampledb.sql (Replace <password> with the real password for the MySQL user root! Important: There is nospace between -p and <password>!)

This will create an SQL dump of exampledb in the file exampledb.sql. Transfer this file to your slave server!

If you want to go the LOAD DATA FROM MASTER; way then there is nothing you must do right now.

mysql -u root -p
Enter password:
UNLOCK TABLES;
quit;

Now the configuration on the master is finished. On to the slave…

2 Configure The Slave

On the slave we first have to create the database exampledb:

mysql -u root -p
Enter password:
CREATE DATABASE exampledb;
quit;

mysql -u root -p<password> exampledb < /path/to/exampledb.sql (Replace <password> with the real password for the MySQL user root! Important: There is no space between -p and <password>!)

If you want to go the LOAD DATA FROM MASTER; way then there is nothing you must do right now.

server-id=2
master-host=192.168.0.100
master-user=slave_user
master-password=secret
master-connect-retry=60
replicate-do-db=exampledb

Then we restart MySQL:

/etc/init.d/mysql restart

mysql -u root -p
Enter password:
LOAD DATA FROM MASTER;
quit;

If you have phpMyAdmin installed on the slave you can now check if all tables/data from the master exampledb is also available on the slave exampledb.

mysql -u root -p
Enter password:
SLAVE STOP;

In the next command (still on the MySQL shell) you have to replace the values appropriately:

CHANGE MASTER TO MASTER_HOST=’192.168.0.100′, MASTER_USER=’slave_user’, MASTER_PASSWORD=’<some_password>‘, MASTER_LOG_FILE=’mysql-bin.006′, MASTER_LOG_POS=183;

• MASTER_HOST is the IP address or hostname of the master (in this example it is 192.168.0.100).
• MASTER_USER is the user we granted replication privileges on the master.
• MASTER_PASSWORD is the password of MASTER_USER on the master.
• MASTER_LOG_FILE is the file MySQL gave back when you ran SHOW MASTER STATUS; on the master.
• MASTER_LOG_POS is the position MySQL gave back when you ran SHOW MASTER STATUS; on the master.

Now all that is left to do is start the slave. Still on the MySQL shell we run

START SLAVE;
quit;

That’s it! Now whenever exampledb is updated on the master, all changes will be replicated to exampledb on the slave. Test it!

The configuration file supports options for multiple programs. Each program has its own directive, which is a keyword in square brackets, such as [mysqld] or [client]. Here is a sample configuration file from a production system:

# The following options will be passed to all MySQL clients

[client]

port = 3306

socket = /var/lib/mysql/mysql.sock

[mysqld]

#this will prevent mysql from starting

port = 3306

socket = /var/lib/mysql/mysql.sock

datadir =/var/lib/mysql

log_slow_queries = /var/log/mysql/mysqld_slow-queries.log

long_query_time = 4

max_connections=200

max_connect_errors = 400

wait_timeout=7200

connect_timeout=10

key_buffer = 512M

tmp_table_size = 32M

max_heap_table_size = 32M

max_allowed_packet = 32M

table_cache = 1800

join_buffer_size = 8M

sort_buffer_size = 16M

read_buffer_size = 8M

read_rnd_buffer_size = 524288

myisam_sort_buffer_size = 256M

thread_cache_size = 384

bulk_insert_buffer_size = 8M

query_cache_limit = 4M

query_cache_size = 128M

query_cache_type = 1

362

MySQL Server Tuning 10

query_prealloc_size = 65536

query_alloc_block_size = 131072

# Try number of CPU’s*2 for thread_concurrency

thread_concurrency = 4

#innodb configuration

innodb_data_home_dir = /mysql/data

innodb_data_file_path=ibdata1:200M:autoextend

innodb_log_group_home_dir = /mysql/data/data

innodb_log_arch_dir = /mysql/data/data

innodb_buffer_pool_size = 24576M

innodb_additional_mem_pool_size = 32M

innodb_log_file_size = 1024M

innodb_log_files_in_group = 2

innodb_log_buffer_size = 16M

innodb_flush_log_at_trx_commit = 1

innodb_lock_wait_timeout = 120

sync-binlog = 1

innodb_support_xa = 0

innodb_thread_concurrency = 128

innodb_file_per_table

# binary logging is required for replication

log-bin=mysql-bin

max_binlog_size = 1024M

server-id = 4

slave-skip-errors = 1062

expire-logs-days = 7

[mysqldump]

quick

max_allowed_packet = 16M

[mysql.server]

user=mysql

group=mysql

basedir=/var/lib

[mysqld_safe]

nice = -5

open_files_limit = 8192

log-error=/var/log/mysql/mysqld.log

pid-file=/var/run/mysqld/mysqld.pid

RAID
(Redundant Array of Independent Disks)

Raid 0 (zero): Only One Copy of Data spread out into Multiple Disks. if One copy Lost all the Data is Lost.

Raid 1 : Two Disks Mirrored if one fails Other will Pickup.

Raid 5: Combines Three of more Disks.  Storage Capacity is Reduced by One Disk.

Raid 10: Combination of Raid 1 and 0 Storage Capacity – 50% Mirrored.

Linux:

LVM: Logical Volume Manager: Which will Separate Log Files on a Different Server.

File System

EXT 2: Good Perfoermance & Slower Crash Recovery.

EXT 3:  Good Performance over EXT2 Filer System.

IBM JFS:  Fast Recovery After a file System Failure.

Tuning MYSQL Server

Show Innodb Status: Which will show all the Status Information of Tables, Queries, Locks, Memory Usage, Memory Dumps, Cache, Flushed Transactions, Thread information Etc.

SHOW VARIABLES: Displays all variables and the usage    ex: Show Global Variables Like ‘%tmp%/’

By default, SHOW STATUS will show SESSION variables. This may or may not be your intention, so to avoid confusion, always specify GLOBAL or SESSION as a keyword.

mysql> SHOW GLOBAL STATUS LIKE ’%tmp%’;

+————————-+———+

| Variable_name | Value |

+————————-+———+

| Created_tmp_disk_tables | 2744623 |

| Created_tmp_files | 147344 |

| Created_tmp_tables | 5003238 |

+————————-+———+

The SHOW VARIABLES can be used to determine the values of system variables. This is a very useful command when tuning a server. As with the SHOW STATUS command, it can use the LIKE modifier, and you should always specify GLOBAL or SESSION to avoid possible confusion.

If you wanted to see the global settings for temporary tables:

mysql> SHOW GLOBAL VARIABLES LIKE ’%tmp\_%’;

+——————-+———-+

| Variable_name | Value |

+——————-+———-+

| max_tmp_tables | 32 |

| tmp_table_size | 33554432 |

+——————-+———-+

“max_tmp_tables”,”32″

“slave_load_tmpdir”,”/tmp”

“tmp_table_size”,”16777216″

“tmpdir”,”/tmp”

INNODB Performance Tuning  Parameters

INNODB_BUFFER_POOL_SIZE : 70-80% memory can be allocated to Buffer Pool size, Set it to 12gb on a 16gb box.

INNODB_LOG_FILE_SIZE:  This Depends on your Recovery Speed but 256mb Seems to be a good balance between Reasonable Recovery and Good Time Performance.

INNODB_LOG_BUFFER_SIZE: This can be Set to the

INNODB_FLUSH_LOG_AT_TRX_COMMAND: Works good before Server Crashes.

INNODB_THREAD_CONCURRENCY: 8

INNODB_FLUSH_METHOD: O-Direct

INNODB_FILE_PER_TABLE:

Transaction Isolation: Read Committed: This Option has some performance Benefits especially in locking in 5.0 and Even more to come with MySQL 5.1 and Row Level Application

Application Tuning for INNODB:

ERROR log:  Sql Daemon Start Stop, Critical Errors will be Logged in this Error Log File

Binary Log: Update, Delete, Insert,  Statements will be logged to Binary Log file.

General Query Log:  All Select Queries, general data retrieval queries will be recorded.

Slow Query Log:  Queries which are running slow and can be logged in to the file.

To activate the query log, simply place:
log-slow-queries = [slow_query_log_filename]
in your configuration file (my.cnf or my.ini), slow_query_log_filename being the optional filename for your log file. If you don’t supply a filename, the default name will be used, which is the name of the host machine, with -slow.log being appended.

The slow query log logs all queries that take longer than long_query_time, which is usually 10 seconds by default (more than long enough for a self-respecting query to complete). You can alter the long_query_time in the configuration file. The following example sets the time to 5 seconds:
set-variable = long_query_time = 5
The slow query log can also optionally log all queries that don’t use an index by placing the following in the configuration file:

log-long-format

s of MySQL 5.1.6, the destination can be a file or a table, or both
mysqld with the --log-slow-queries[=file_name] option to enable the slow query log, and optionally use --log-output to specify the log destination (as described in Section 5.2.1, “Selecting General Query and Slow Query Log Output Destinations”).

Tee:  Turns on MYSQL Logging  to a specified file. ex: Tee / Filename,
NoTee:  Will stop logging mysql.

Memory Storage Engine Configuration

max_heap_table_size: The Maximum size of memory tables is limited by the system variable, it has a default value of 16 mega bytes.

Init_File: This can be used to specify a file to use to populate a memory table  when mysqld starts, for ex: the file may contain LOAD DATA INFILE Command.

Maria Storage Engine is a Crash Safe Version of MYISAM.

Overall MySQL Server Options

 

Overall MySQL Server Options

Option Name Global or

memlock Global
Locks the mysqld daemon into server memory. While this can improve performance if the server runs out of RAM, the mysqld daemon will crash.

sort_buffer_size = buffer_size
Session Determines the amount of system memory allocated for SQL sorts. If this size is exceeded, the server will use hard drive space for sorting data.

thread_cache_size = num_of_threads
Global mysqld creates a cache of unused connection threads rather than destroying threads and creating new ones as need.

thread_concurrency = N Global
Only use on Solaris systems. This should typically be set to twice the number of CPUs. It should be tested carefully before using in production.

tmp_table_size Global
Both this and the max_heap_table_size setting are used to determine the maximum size allowed of an in-memory temporary table before it is converted to a MyISAM table. The smallest value for these two settings is the one utilized.

MOCA (MYSQL Optimal Configuration Architechture)

1)  /opt/Mysql/5.1.33           -------------- Software Installed at this Location
2) db01/mysql/mysql01/data --------  Data Directory
Db01/mysql/mysql01/binlogs    ------------- binary logs directory
Db01/mysql/mysql01/admin       ------------ main administration

 

Db01/mysql/mysql01/Backups   ————  Backups
Db01/mysql/mysql01/Trans        ————  Transaction Data Files
Db01/mysql/mysql01/TransLogs  ———-   Trans Log Files.

Backup Strategies and Backup Procedures.

Logical Backup: Taking Backup Online While Database is Running.

Physical Backup: Taking Backup of Database Files or Disk Partitions: Occupies More Space.

Full Backup: Taking Full Backup of Database.

Incremental Backup: Taking Backups of the Database Since the last Backup.  You may take first full Backup and take Incremental Backups to Save Time. Once a Week full backup might be necessary.

Consistent Backup: Taking Backup at an Exact Moment of Time, A Backup Process may take time to Complete
HOT Backup: Taking Backup while Database is Running.
Cold Backup: Taking Backup While Database is Offline.
Point-in-Time-Restore: Restoring Backup for Certain Time and Date.

REPLICATION – - Configuring Slave Backup Server.

Restore Database and Execute a CHANGE MASTER Command to configure the Slave.

LOAD DATA FROM Master – Master to Slave.
Grant Replication Slave on *.* to ‘Slave’ @ ‘Slave-host’ Identified by ‘Password’ ;

2) Edit My.cnf   Configuration file and add the below line

[mysqld]
Server-Id  =  1
Log – bin = Slave_log

Show Master Status;

Partition PO Values Less than (To_Days (‘2009-01-01)),
Partition PO Values Less than (To_Days (‘2009-02-01)),
Partition PO Values Less than (To_Days (‘2009-03-01)),
Partition PO Values Less than (To_Days (‘2009-04-01)),
Partition PO Values Less than (To_Days (‘2009-05-01)),
Partition PO Values Less than MAXVALUE.

Binlog
Partition
CSV
MEMORY
InnoDB
MyISAM
MRG_MYISAM
ndbcluster – DISABLED – needs to be downloaded and Installed in order to work.

INNODB Row Level Locking

Create the Repository (don’t import any of your working copies or anything.. just the clean repository).

to Create a Repository issue the below command.

svnadmin create –fs-type fsfs /srv/svn/repos

if your Svn Backup is saved in .tgz format i.e., backup.tgz then unzip it first using the command

tar -xvzf filename.gz

for ex: tar -xvzf 030001.tgz will unzip the file in your given location with a dumpfile as saved previously by the command script.

then run the below script to restore the Repository from Backup.

svnadmin load <

ex: #svnadmin load /srv/svn/repos < /home/sree/Desktop/030001/dumpfile.txt

then the dumping process will start and dump all the revisions inside the Selected Folder.

check your repository before updating or committing any of your new files.

here are some of the external bash commands if you need for your directory removal with some content in it.

ex: rm -rf repos (will delete main folder and sub folders inside)

if you have any issues please leave a comment.

to set the Cron Job for SVN use the below commands

#crontab -l will list out all the cron jobs

#crontab -e    will edit the cron job file in VI Editor.

“MAILTO=chava.sree@gmail.com”
0 3 * * * /srv/svn/backup/inc_backup.sh

will do incremental backups everyday.

this is the Reference URL  http://www.cyberciti.biz/faq/how-do-i-add-jobs-to-cron-under-linux-or-unix-oses/

Thanks
Sree.

Issue:
Figured out Apache Server is not running when i run the command “service httpd status” until then i am running http://localhost/ in the browser which is working fine and unable to run any other programs

and when i used this command “# service httpd status: i got the below message

[root@hirodexdbserver ~]# service httpd status
httpd dead but subsys locked

i thought it might be some locks issue and restarted the server

#service httpd restart – i got the below error again.
**********************
[root@hirodexdbserver ~]# service httpd restart
Stopping httpd: [FAILED]
Starting httpd: (98)Address already in use: make_sock: could not bind to address [::]:80
(98)Address already in use: make_sock: could not bind to address 0.0.0.0:80
no listening sockets available, shutting down
Unable to open logs
[FAILED]
You have mail in /var/spool/mail/root
[root@hirodexdbserver ~]# service httpd restart
**********************

Steps to Resolve the Issue
——————————–
after figuring out and looking at my httpd.conf file and make sure the pid file is pointing to the right file

PidFile run/httpd.pid

and change the path here to
go to /etc/rc.d/init.d/httpd open this file
and find the below line.

pidfile=${PIDFILE-/var/run/httpd/httpd.pid}

to:
pidfile=${PIDFILE-/var/run/httpd.pid}

Restart the Apache Server

# service httpd restart
Stopping httpd: [ OK ]
Starting httpd: [ OK ]

which should give you the above status.

hope this helps.

Thanks

echo “+++ Backing up subversion repositories”
NOW=`date +”%OH%M%S”`
cd backup
mkdir -p $NOW
svnadmin dump /srv/svn/repos > $NOW/dumpfile.txt
tar cfpz $NOW.tgz $NOW .
rm -rf $NOW
echo “+++ Svn Backup Successfully Completed. Thank you”

http://bash.cyberciti.biz/backup/copy-all-local-files-to-remote-ftp-server-2/

# Subversion Repositories backup script

# Please start configuring here
svnbasedir=”/srv/svn”
svnfullbkdir=”/srv/svn/backups/full” #Don’t put a trailing slash!
logfile=”/srv/svn/backups/log.txt”
tmpdir=”/tmp”

# dont change below

#check if log file exists
touch ${logfile}
#redirect stdout and stderr to the logfile
mkdir -p $(dirname ${logfile})
exec >> ${logfile}
exec 2>&1

echo “+++ Backing up subversion repositories”
#Looks for dirs containing a file “format”, that’s not in the /db/ directory.
#This seems to match the root of a SVN repo. YMMV
repos=$(find $svnbasedir -name format -a \! -path ‘*/db/*’ -printf ‘%h\n’)

#Make sure that our backup location exists
mkdir -p ${svnfullbkdir}

for repo in $repos ; do
subpath=$(echo ${repo} | sed -e “s#${svnbasedir}/##”)
name=$(basename $subpath)
subpath=$(dirname $subpath)
echo ” $repo”
lastrev=$(svnlook youngest ${repo})

mkdir -p ${svnfullbkdir}/${subpath}
svnadmin dump -q ${repo} > ${svnfullbkdir}/${name}.dump
echo “Dumping ${repo} to ${name}.dump \n”

done

RESTORE

#!/bin/sh
# Subversion Repositories backup script

# Please start configuring here

svnbasedir=”/svn/svn”
svnfullbkdir=”/tmp/svn-dump” #Don’t put a trailing slash!
svnincbkdir=”/subversion/backup/incremental”
logfile=”/subversion/backup/log.txt”
tmpdir=”/tmp”

# dont change below

touch ${logfile}
#redirect stdout and stderr to the logfile
mkdir -p $(dirname ${logfile})
exec >> ${logfile}
exec 2>&1

echo “+++ Restoring subversion repositories “
#Looks for subversion backup dumps taken before
repos=$(find $svnfullbkdir -name ‘*.dump’ )

mkdir -p ${svnbasedir}

for repo in $repos ; do

dirname=${repo%.dump}
name=$(basename $dirname)
$curpath = “/svn/svn/”.${name}
echo ” creating reposity ${name} at ${curpath} “
svnadmin create /svn/svn/${name}

echo ” loading ${repo} “
svnadmin load -q /svn/svn/${name} < ${repo}

done

***** ANOTHER WAY OF BACKUP ***********

http://www.linuxquestions.org/questions/linux-server-73/svn-server-backup-574111/

incremental backup..

# svnadmin dump –incremental /srv/svn/repos | gzip -c > /srv/svn/dumped.gz

Actual Code

#!/bin/bash

NOW=`perl -e ‘print time;’`
cd /var/backup/svn
mkdir $NOW
svnadmin dump /opt/repositories.svn/CC > $NOW/dumpfile.txt
tar cfpz $NOW.tgz $NOW
rm -rf $NOW

…then follow that up with another cronjob that does this:

CRON JOB

45 3 * * * for i in `find /var/backup -type f -mtime +2` ; do rm -f $i ; done

The first cronjob does a full dump of the svn database and then zips it. (We are paranoid, we only do full dumps of databases and database-like applications.) Later on after that’s complete, the nightly backup process runs and the full dump is taken as part of a daily backup to tape. The second cronjob deletes anything it finds in the /var/backup tree that’s older than two days. That way I know I have two days of backups on disk, and I can restore the full database from any day I have tape for.

How to Add a script to Cron Job.
——————————–

Physicians, attorneys, accountants, engineers, realtors, and many other professionals have written guidelines designed to discourage misconduct and illegal activity, and to promote the ethical conduct of its members. In fact, according to the Sarbanes-Oxley act, all public companies in the United States are required to create and follow their own code of conduct.

if, as a DBA, you
identify criminal
behavior within
your organization,
what do you do?

However, despite the fact that DBAs are essentially protectors of an organization’s knowledge, and privy to much confidential information, there are no clearly-defined set of rules, values, standards, and guidelines to help govern and guide their behavior.

In this article, I define what a code of conduct is, explain how it can be useful to DBAs and the organizations they work for, and consider if and how it could be enforced. Finally, I offer my take on a “Code of Conduct” for the Exceptional DBA. Rather than be prescriptive, my goal is simply to offer advice to DBAs on how they might conduct themselves within the bounds of the professional responsibilities of their job.

What is a Code of Conduct?

Generally speaking, a code of conduct is a set of formal, written rules, policies, standards, guidelines, obligations, behaviors, expectations, and principles that are voluntarily adhered to by a group of people with similar goals, values, and responsibilities. While other definitions exist, this one will serve our purpose well enough, as we seek to define the standards of conduct to which a DBA should adhere, while carrying out their professional duties.

How Can a Code of Conduct be Useful to DBAs?

To many people, a “Code of Conduct” means one thing: more rules. Most DBAs, myself included, would consider themselves mature enough to make their own decisions and choices, and are naturally resistant to the idea of someone telling them what to do and how to do it.

If this is the case, then why have I written this article? Well, first, my intent is not to offer a set of rules that have to be followed but, instead, a set of guidelines that can be useful for DBAs who want to fully understand and appreciate the nature and scope of their duties and responsibilities. In other words, it is intended to be educational.

It’s a sad fact that
many organizations
don’t fully understand
and appreciate the
true role of a DBA.

At a fundamental level, most DBAs believe they understand what it means to behave “ethically”. In my experience, instances of willful negligence, or blatantly unethical behavior, are relatively scarce in our profession. However, there are many “grey” areas where a DBA, especially a less-experienced DBA, can find themselves unsure of where their responsibilities end, and how exactly they should respond to a potentially compromising situation.

For example if, as a DBA, you identify criminal behavior within your organization, what do you do? Hopefully, your answer would be that you’d report it. However, is that the end of your responsibilities? What if the company you work for does not respond appropriately? What further action should you take, if any?

It’s a sad fact that many organizations don’t fully understand and appreciate the true role of a DBA. In their attempts to save money, they sometimes cut corners that can directly affect the integrity of their data, and so unwittingly place the guardians of their data in a difficult dilemma. If you find yourself in this situation then, hopefully, this code of conduct may help convince your organization of the importance of the role of the DBA, and the need to employ experienced DBAs to safeguard their business data. For example, if you are having difficulty convincing your manager to adhere to government regulation that affects the data you manage, then referring the manager to this Code of Conduct might be useful.

Perhaps above all else, the “Exceptional DBA’s Code of Conduct” can be a source of pride to all of us who choose to adhere to it, and give us more confidence that we are doing the best we can at our jobs.

How Should a Code of Conduct be Implemented and Enforced?

Whenever the topic of a “code of conduct” is discussed, one of the first questions to be asked is: how can it be enforced? After all, if the code is not enforced in any way then, it is argued, who is it benefiting? There is no straightforward answer to the question of how to enforce such a code, or even if it should be enforced, rather than be voluntary.

One suggestion is that the code be enforced by an independent, professional organization, such as the ACM, AITP, or PASS. Anyone who fails to follow the established code of conduct could have their membership of the organization revoked. On the assumption that most businesses would regard membership of the organization a key requirement in their hiring process, then it could, in theory, prove an effective deterrent to malpractice.

Again, any DBA who fails
to follow the established
code could have their
certification rescinded.

Another suggestion is that organizations that offer DBA certifications, such as Microsoft, should enforce some code of conduct. Again, any DBA who fails to follow the established code could have their certification rescinded. Obviously, this would only be an effective measure for organizations that require certification as part of their terms of employment. On the other hand, if Microsoft were to attempt this, what about the Oracle and MySQL DBAs? Would they need a separate code that is tied to their certifications?

Another option is to have a DBA Code of Conduct enforced on a per-organization basis. After all, many organizations already require their employers to abide by a “code of conduct,” often in the form of an employee handbook. Such a code could be expanded to incorporate conduct specific to DBAs. On the other hand, if a company creates a separate code of conduct for DBAs, wouldn’t it also have to create different codes of conducts for other job titles? Again, this is not a great solution.

In light of the numerous complications of implementing and enforcing a DBA’s Code of Conduct, I suggest that following such a code, or not, is a personal choice on behalf of the individual DBA. As I noted earlier, I regard such as code as being primarily educational in nature, with the rewards for following it being a successful, rewarding, long-term, and satisfying career as a DBA. For those who choose not to follow it, well, who knows how their career will turn out? They might get lucky and survive over the long haul, but I doubt if they will ever fall into the Exceptional DBA category.

The Exceptional DBA’s Code of Conduct

This section contains my suggestions for the core items that should comprise “The Exceptional DBA’s Code of Conduct”. My focus is on providing general guidelines that will help any DBA become more successful in their career.

I won’t be so presumptuous as to imply that these guidelines are ideal or exhaustive, but they should hopefully get you thinking and be useful as a guide to you in your role as a DBA.

Protection and Disclosure of Data

1. DBAs shall never intentionally do anything that contributes to the corruption or loss of an organization’s data. While this should be a no-brainer, I am including the obvious, just to cover all the bases.
2. Above all else, the DBA is the guardian, or protector, of an organization’s data. The responsibilities of the DBA in this regard include but are not limited to:
   • Preventing data corruption (from applications, hardware, and people).
   • Provide high data availability, as defined by the organization’s policy. Develop, and regularly test, a disaster recovery plan to minimize unexpected downtime, as defined by the organization’s policy.
3. DBAs shall take all reasonable precautions to ensure that changes to a production server have no detrimental consequences. All proposed changes should be thoroughly tested on a test server prior to deployment to production.
4. DBAs shall proactively take all the necessary steps to ensure that data can only be accessed by authorized users. This may include, but is not limited to: SQL Server security, Windows Authentication security, encryption, SQL injection attack prevention, auditing, or other such security policies, as defined by their organization.
5. DBAs generally have full access to all the data in a database. This presents two important points:
   • DBAs shall only view data in a database if they need to access it to perform their job duties. For example, a DBA may need to access data to optimize a query or create a report. But if the DBA doesn’t need to access and view data for job-related tasks, then DBAs shall not snoop through the data for the sake of viewing it.
   • If, through the course of their required job duties, DBAs do view confidential data, DBAs shall not share any sensitive or confidential information with any unauthorized users.
6. DBAs shall provide full cooperation with both inside and outside audits, providing truthful and factual information
7. If the DBA learns that contractors, co-workers, or managers are making poor choices that could negatively affect the integrity or security of the organization’s data, then the DBA should notify the appropriate persons within their organization.
8. If a DBA discovers misuse of an organization’s data, then the DBA should report this behavior to the appropriate persons within their organization.
9. The DBA should maintain proper and complete documentation for all servers and processes for which he or she is responsible. The documentation should be of a form and standard that will allow a qualified peer to undertake the task, in the DBA’s absence. The DBA should never protect (hide) information from their organization that would prevent another person from easily taking over his or her position, should the need arise.

DBAs and the Law

1. Often, the data under the care of a DBA is subject to laws and regulations of one or more governing bodies. The DBA shall become familiar with these laws and regulations, and adhere to them.
2. The DBA shall enforce all software licensing agreement with vendors, and notify the proper people in the organization if any breech is discovered.
3. If the DBA becomes aware of illegal activity within their organization, the DBA shall notify the proper people in their organization, or the appropriate law enforcement agency.

Dealing With Third-Parties

1. DBAs shall not accept gifts or favors from vendors if the purpose of the gift or favor is to influence, or to reward, the DBA’s choice of purchasing goods and services from the vendor. More specifically:

• • The DBA shall proactively learn their organization’s policies about gifts, so they know what they can or cannot accept. For example, company policy might allow a vendor to take a DBA to dinner, or to receive a free gift at a conference or a user’s group meeting. On the other hand, an organization’s policy might limit the amount of the gift to a maximum value, such as $50.00.
  • The acceptance of a gift, even if allowed by the organization, should not influence the behavior of the DBA in regards to potential purchase of the vendor’s products and services.
  • Whenever a DBA purchases, or influences the purchase of goods or services, the DBA should only purchase those good or services because they are the ones that best meet the needs of the organization.

General Conduct

1. The DBA shall conduct himself, or herself, professionally in all relationships with the people they deal with on a daily basis, including managers, co-workers, vendors, and their “internal customers.” Favoritism and discrimination of any sort is to be avoided.
2. If a DBA makes a mistake, and all DBAs make a mistake at one time or another, the mistake should be fixed as soon as is practical, and the DBA should inform everyone who might be negatively affected by the mistake as soon as possible. In addition:
   • Mistakes should never be covered up.
   • DBAs should take full responsibility for all their decisions.
3. If a DBA has management responsibilities, the DBA should mentor those who need help accomplishing their objectives, and allow those with experience and enthusiasm to succeed and flourish within the environment he or she provides for them.
4. The DBA will do their job to the best of his or her ability, developing and implementing best practices as appropriate, to help ensure the smooth and successful operations of the organization’s databases.
5. IT technology changes quickly. It is the responsibility of the DBA to proactively keep up on all technical areas that directly affect his or her job.
6. If the DBA has agreed to a SLA (Service Level Agreement) for the servers under their care, then they will abide by those agreements. If they are not technically able to abide by the agreed upon SLA (for whatever reason), the DBA needs to contact the SLA owner and work out how to resolve the problem.
7. Occasionally, the DBA may find that there is no established policy with regard to a particular aspect of their duties. For example, perhaps an organization doesn’t have a policy that defines the desired level of uptime, or that defines who can access what data. In areas where policies should be established (to ensure the protection and integrity of the organization’s data), but are not established, the DBA shall proactively identify the areas of need, make recommendations, and present them to the organization’s management so they can make appropriate decisions.

It is impossible to provide advice to guide a DBA through every aspect of their duties and responsibilities as a DBA, and there are many “grey areas”. What does the DBA do when they notify the appropriate persons of an important issue that could negatively impact the organization’s data, and no action is taken to rectify the issue? Where do a DBA’s responsibilities end with regard to uncovering illegal activity within an organization? What does a DBA do when a cost-cutting measure means they feel they can’t fully adhere to their own code of conduct? These are all difficult question for any employee, not just a DBA.

If you, as a DBA, feel “pressured” to do something you are uncomfortable doing, then the best advice I can give is to talk to people. In most cases, the first step is to tell your manager, co-worker, project manager, or whoever is causing the problem, that you feel uncomfortable with their request, action or inaction, and explain why. If they don’t want to listen, your next option is to escalate the issue to their manager. You may, or may not, receive management support for your case. If not, then you have to decide to “give in,” or to find another job.

The key thing is that the DBA needs to keep cool and not take any rash action. Before making an important decision that could potentially hurt your career, talk over the issue with people you trust in order to get their feedback and input. Only take action once you have clearly and thoughtfully considered the consequences of your choices. This might mean keeping quiet and not making trouble, escalating the issue to higher levels of management, reporting a crime to an enforcement agency, or finding a new job.

Summary

My goal in suggesting an “Exceptional DBA’s Code of Conduct” is to provide advice and guidance for those DBAs wanting to learn more about what it takes to become an Exceptional DBA. Is the code complete or perfect? Of course not. Consider it a working, educational document; it is certainly not intended to be an absolute set of rules that every DBA must always follow.

My hope is that it serves as a useful guide to the DBAs looking to navigate the “grey areas” and as a foundation for all those entering the profession with ambitions to become Exceptional DBAs.

  ERROR 1418 (HY000) at line 253: This function has none of DETERMINISTIC, NO SQL, or READS SQL DATA in its declaration
               and binary logging is enabled (you *might* want to use the less safe log_bin_trust_function_creators variable)

for the above error just set the below parameters in my.ini (for windows) and my.cnf (in linux) files to edit and add the below text.

in windows to edit the my.ini file go here c:/program files/mysql/mysql version5.4/bin/my.ini

in linux to edit the my.cnf file go here /etc/mysql/bin/my.cnf and add the below line to your config file.

 log_bin_trust_function_creators=1

1. yum install subversion
2. yum install mod_dav_svn

Creating a User in Svn using the bash Command

1) htpasswd -cm users sam
2) htpasswd -cm users chava
3) htpasswd -cm users veera

Importing a Folder to Repository in Svn (to checkout for later use)

1) svn import -m "Initial Import" local-directory-projectX http://server-name/svn/projectX

2)

follow this link to install subversion Server 1.4 on Linux Server with Apache WebServer Running

http://www.yolinux.com/TUTORIALS/LinuxSubversionAndTracServer.html

Create a Subversion repository using the FSFS database format: (as root)

• mkdir /srv/svn/repos
• svnadmin create --fs-type fsfs /srv/svn/repos
• chown apache:apache -R /srv/svn/repos
  (The Apache web server running as user “apache” is the process owner which will be interfacing with the Subversion repository.)
• SELinux security attribute assignment: (Red Hat EL4+, Fedora 3+)
  restorecon -R /srv/svn/repos

Apache configuration file: /etc/httpd/conf.d/subversion.conf

• This example performs no authentication:
  

  LoadModule dav_svn_module modules/mod_dav_svn.so - Required for Apache interface LoadModule authz_svn_module modules/mod_authz_svn.so - Required for "per-directory" access control <Location /svn> - URL path in web browser after "http://domain.com/" DAV svn SVNPath /srv/svn/repos - Local path on server filesystem </Location>

• This example authenticates to a local Apache user password file: User logins and passwords have no connection to user accounts.
  

  LoadModule dav_svn_module modules/mod_dav_svn.so LoadModule authz_svn_module modules/mod_authz_svn.so <Location /svn> DAV svn SVNPath /srv/svn/repos AuthType Basic AuthName "Subversion Repository" AuthUserFile /etc/httpd/conf/userpw require valid-user </Location>

  Remove the line “require valid-user” to allow read-only access for unauthenticated users.

Importing Directory of Files Into Subversion:

Subversion Repository on Server File system:

• /srv/svn/repos

Import directory of files into Subversion:

• Local directory to import into Subversion:
  • projectX/trunk/...source code goes here...
  • projectX/branches
  • projectX/tags
• svn import -m "Initial Import" local-directory-projectX http://server-name/svn/projectX
  The import will create the new subdirectory branch “projectX” in the repository.

Alternate directory creation method: (repository exists but the directories need to be generated)

• svn mkdir -m"Initial creation of trunk directory" http://svn-server/svn/projectX/trunk
• svn mkdir -m"Initial creation of branches directory" http://svn-server/svn/projectX/branches
• svn mkdir -m"Initial creation of tags directory" http://svn-server/svn/projectX/tags

Browser view of a typical repository directory schema:

• http://svn-server/svn/projectX/trunk: For the “HEAD”
• http://svn-server/svn/projectX/branches: For branches or “forks” in the code.
• http://svn-server/svn/projectX/tags: For tags identifying snapshots of milestones or significant releases.

• /trunk : Contains the current development branch. New projects should be started here.
• /branches : A branch is just a special copy of the source tree within Subversion that started with a specific revision of the code. A branch is created by using “svn copy” of the trunk to a branch i.e. /branch/name_of_branch_1.0.
• /branches/personal : Personal branches are for doing some work which you don’t want to have interfere with the main trunk until it is working or better defined.
• /tags : This is a ethod of bookmarking or taking a “snapshot” of some work in progress.
• /releases : This is similar to “tags” except that this version of the code makes it to production. Names used here should match product release names. i.e. version_1.1

Avoiding false diffs due to “^M” in a cross platform environment:

The Microsoft development tools love to add a “^M” at the end of the line of every file they edit. This breaks UNIX shell script and causes many file difference tools to show a difference in a line of code. This can be avoided in a cross platform environment by telling Subversion that certain files (or all files) that no “^M”‘s should be appended at the end of a line. The trigger in fact removes the “^M” when the file is checked in. It can also be removed using the command dos2unix.

Import files to support no “^M” carriage returns at the end of lines:
(This sets file properties and creates a check-in trigger.)

• Remove “^M” from files: find local-directory -name "*.cpp" -exec dos2unix {} \;
• Upload directory of files into Subversion:
  svn import -m "Initial Import" local-directory http://server-name/svn/projectX
• Checkout files from repository: svn co http://server-name/svn/projectX/trunk
  This creates your local working directory under Subversion control.
• Set file properties such that “^M” are removed during check-in if added:
  find ./ -name "*.cpp" -exec svn propset svn:eol-style LF {} \;
• Apply property changes to repository: svn ci -m "Apply LF properties" local-directory

Note that the “propset” command must be used for new files added to the Subversion repository if they are to have these properties.

Users can also set this option in the file: $HOME/.subversion/config

..
...

[auto-props]
README = svn:eol-style=native
INSTALL = svn:eol-style=native
*.c = svn:eol-style=LF
*.cpp = svn:eol-style=LF
*.h = svn:eol-style=LF
*.dsp = svn:eol-style=CRLF
*.dsw = svn:eol-style=CRLF
*.sh = svn:eol-style=native;svn:executable
*.txt = svn:eol-style=LF
*.png = svn:mime-type=image/png
*.jpg = svn:mime-type=image/jpeg
Makefile = svn:eol-style=LF
*.html = svn:eol-style=LF
*.css = svn:eol-style=LF
*.java = svn:eol-style=LF
*.xml = svn:eol-style=LF
*.m4 = svn:eol-style=LF
*.pdf = svn:mime-type=application/pdf

...
..
Data repository dump:

Dump first entry to current:
 svnadmin dump /srv/svn/repos --revision 0:HEAD > repos.dump
Dump revision 625 to current:
 svnadmin dump /srv/svn/repos --revision 625:HEAD --incremental > repos-625.dump

*************************************************************************************************************


TROUBLESHOOTING SUBVERSION.
---------------------------

use the below path 

run the below commands first to make sure you are giving access to the repos folder.

use these vi commands to edit the file.

vi filename.

examples: http://www.cs.colostate.edu/helpdocs/vi.html

chown apache:apache -R /srv/svn/repos

restorecon -R /srv/svn/repos

edit this file and add the below script.

/etc/httpd/conf.d/svnserve.conf

enable these statements below

anon-access = read
auth-access = write

<Location /svn>
 DAV svn
 SVNPath /srv/svn/repos
 AuthType Basic
 AuthName "Subversion Repository"
 AuthUserFile /srv/svn/access/users
 require valid-user
</Location>