How to Upload Files on Google Drive from Linux Console

Follow below steps to use google drive from linux termial

Download google drive version for linux
wget https://docs.google.com/uc?id=0B3X9GlR6EmbnWksyTEtCM0VfaFE&export=download

yum install wget
wget https://docs.google.com/uc?id=0B3X9GlR6EmbnWksyTEtCM0VfaFE&export=download

You will see a file like above. Rename it with gdrive
mv uc\?id\=0B3X9GlR6EmbnWksyTEtCM0VfaFE gdrive

chmod +x gdrive

install gdrive /usr/local/bin/gdrive

Run below command to check

[root@bhagwat home]# gdrive list
Authentication needed
Go to the following url in your browser:
https://accounts.google.com/o/oauth2/auth?access_type=offline&client_id=367116221053-7n0vf5akejinrecpdoe99eg.apps.googleusercontent.com&redirect_uri=urn%3Aiet%3Awg%3oau%3A2.0%3Asponse_type=code&scope=https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fdrive&state=state

Enter verification code:

Just copy the above url & paster in your browser. Copy verification code here & you are done. Now you can use your google drive directly from terminal.

Upload any file with below command
[root@bhagwat home]# gdrive upload my_photos.zip

Use gdrive help command for more options
[root@bhagwat home]# gdrive help

Find files with specific extensions in current directory

Find files with specific extensions in current directory (you can add multiple extensions as per syntax

find . -type f \( -name "*.sh" -o -name "*.txt" \)
find /home/bhsingh/ -type f \( -name "*.png" -o -name "*.jpg" -o -name "*.deb" -o -name ".pdf" \)

Find file & redirec the result to a file

find /home/www/html -type f \( -name "*.php"\) -print0 | xargs -0 stat --format '%Z :%z %n' | sort -nr > /home/bhsingh/php_files.txt
find / -type f -print0 | xargs -0 stat --format '%Z :%z %n' | sort -nr > /root/all_files.txt

Not able to install googleads-php-lib on Centos

[bhagwat@server1 googleads-php-lib-25.1.0]$ php composer.phar require googleads/googleads-php-lib

Using version ^25.1 for googleads/googleads-php-lib
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

Problem 1
- The requested package googleads/googleads-php-lib No version set (parsed as 1.0.0) is satisfiable by googleads/googleads-php-lib[No version set (parsed as 1.0.0)] but these conflict with your requirements or minimum-stability.


Solution

Issue was resolved after upgrading composer with below command

php composer.phar update

(Composer seems not to be able to detect the version of the library and thus cannot install the library of v25.1 as requested.)

Test hard disk performace on Linux Server

Performance testing was done on /dev/sda drive with cache enable & disable mode of hard drive

cache enable/disable syntax is below
hdparm -W(value) /dec/sda

Value 0 means cache disable
Value 1 means cache enable

One gigabyte was written for the test, first with the cache activated (hdparm -W1 /dev/sda):

root@bhagwat~# dd if=/dev/zero of=/root/testfile bs=1G count=1 oflag=direct
1+0 records in
1+0 records out
1073741824 bytes (1.1 GB) copied, 32.474 s, 33.1 MB/s
root@bhagwat~#


Then, with the cache deactivated (hdparm -W0 /dev/sda):

root@bhagwat~# dd if=/dev/zero of=/root/testfile bs=1G count=1 oflag=direct   
1+0 records in
1+0 records out
1073741824 bytes (1.1 GB) copied, 123.37 s, 8.7 MB/s

Cron need to run on every Monday of the Month

Need to add a cron entry which should execute on every Monday of month.
Or
You can use it for any other day (changing "Mon" with other days")


00 04 1-7 * * [ "$(date '+\%a')" == "Mon" ] && perl /home/bhagwat/cron/my_script.pl
00 04 8-15 * * [ "$(date '+\%a')" == "Mon" ] && perl /home/bhagwat/cron/my_script.pl
00 04 24-31 * * [ "$(date '+\%a')" == "Mon" ] && perl /home/bhagwat/cron/my_script.pl

Find top 10 directroy by size in linux

Find top 10 directroy by size in linux



Simply run below command to display the results

du -hs * | sort -rh | head -10


In few systems the "h" extenion is not working. They can use below command instead

du -s * | sort -rn | awk '{print int($1 / 1024) "M\t"$2}' | head -10

If data is in GBs then there is a little modification in command

du -s * | sort -rn | awk '{print int($1/1024/1024 ) "G\t"$2}' | head -10

Switch one user with other user without password

Switch one user with other user without password (sudoers entry)

You need to allow one user to run switch user & work as other user

Add below entry in sudoers file

user1 ALL= NOPASSWD: /bin/su user2


Now user1 can switch as user2 with below command

sudo su user2

Common Mysql Problems & Solutions

Here are few common Mysql Replication Errors & their solutions

Problem - 1   

Last_Errno: 1594
Relay log read failure: Could not parse relay log event entry. The possible reasons are: the master's binary log is corrupted (you can check this by running 'mysqlbinlog' on the binary log), the slave's relay log is corrupted (you can check this by running 'mysqlbinlog' on the relay log), a network problem, or a bug in the master's or slave's MySQL code. If you want to check the master's binary log or slave's relay log, you will be able to know their names by issuing 'SHOW SLAVE STATUS' on this slave.

Solution

Run Show slave status & Check these 2 positions
Relay_Master_Log_File: db1-bin.002183
Exec_Master_Log_Pos: 9866809

Stop Slave & Reset the same & provide the position you have noted earlier
mysql> stop slave;
mysql> reset slave;
mysql> change master to master_log_file='db1-bin.002183', master_log_pos=9866809;
mysql> start slave;

It's done now. Let the slave recover it's data with Master

#####################################

PROBLEM - 2

ERROR 1872 (HY000): Slave failed to initialize relay log info structure from the repository




This error comes when you are creating new Mysql slave & just started the replication with Master

Solition:

Reset slave;
Stop Mysql
Delete mysqld-relay-bin.index in Mysql folder
Start Mysql
Run Change Master to Master command
Start Slave;


#################################

PROBLEM - 3

Last_SQL_Errno: 1305
Last_SQL_Error: Error 'FUNCTION DB.SPLIT_STR does not exist' on query. Default database: 'DB'. Query: 'insert into tablename(folderid, subuid, company, title, summary, descr, keyskills, job_type, minsal, maxsal, minsal_channel,

Solution -
It is related with functions as the above function is not available at slave server
 
Take backup of functions of DB from destination server
mysqldump -u root -p --routines --no-create-info --no-data --no-create-db --skip-opt  DBName > /home/bhagwat/functions.sql

Restore with below command on Slave
mysql --defaults-file=/root/.my.cnf.root DBNAME < /home/bhsingh/functions.sql


##############################

Problem - 4

ERROR 1235 (42000) at line 21: This version of MySQL doesn't yet support 'multiple triggers with the same action time and event for one table'

Solution -
Add --skip-triggers in command & take backup of functions

mysqldump --defaults-file=/root/.my.cnf.root --routines --no-create-info --no-data --no-create-db --skip-opt --skip-triggers bazooka > /home/bhsingh/bazooka1.sql

##############################

Problem - 5

Last_SQL_Error: Error 'Out of resources when opening file


Solution:

Increase Open files limit on server to fix this  issue

Check current limit with below command
[root@server ~]# mysql -u root -p -e 'show variables;' | grep open
have_openssl    DISABLED
innodb_open_files    300
open_files_limit    8000
table_open_cache    2048


Increase the same with below command

[root@server ~]# cat /etc/security/limits.conf |grep mysql
mysql         soft      nofile     12000
mysql         hard      nofile     16000

For Immediate effect change in below file
 vim /etc/security/limits.d/90-nproc.conf
*          soft    nproc     1024
mysql      soft    nofile    12000
mysql      hard    nproc     16000
root       soft    nproc     unlimited

##########################

Password Protect file in vim text editor

Password protecting file in vim text editor
add +X before any file name & it will prompt you to enter a password

Example
vim +X filename

Now next time it will ask for the password while opening the file

If you don't want the password you can simply remove the same with below stpes
Open you file & press Esc

:set key=
then, save the file

Check public ip address from Linux Command Console

Check public ip address from Linux Command Console

Use below command to check Public IP from linux command console

curl ipecho.net/plain
or
host myip.opendns.com resolver1.opendns.com
or
dig TXT +short o-o.myaddr.l.google.com @ns1.google.com

Print Date/Time with command history

Execute below command on console

export HISTTIMEFORMAT='%F %T'

or make it permanant with entry in your .bashrc file
vim ~/.bashrc

enter this line
export HISTTIMEFORMAT='%F %T'

Apply the changes with below command 
source ~/.bashrc

This trick is also useful when you are trying to check execution time of any command in history.

You can simply run it once on console & check the history. It will removed once you logout from the current session