Various Tech.

Change MySQL user's password in bulk Sometimes we need to change the password of mysql users at bulk. Lets say your company has fired a group of peoples or dissolved a project. This requirement can be supplied as : We can achieve the same by changing the password field in mysql.user table. Password() is a predifined method in mysql which generates encrypted value of a certain string. host update mysql.user set password = PASSWORD("passwd") where host IN (<Comma separated list of HostName/IP>); user update mysql.user set password = PASSWORD("passwd") where user IN (<Comma separated list of ‘user’@’host’>);

nodejs-akamai-page.MD Overview In almost every blog when people talk about deploying something on K8S they use node mostly because setting up http server is not that easy. I wish that it could be this easy for our case, (which it wasn’t). Manly because the way we wanted the application to work, plans for SEO and multiple data pipelines for business including Amplitude for client and Pubsub for application and business metrics. Making all these calls from nodejs was easy for developers just 1 more promise. Everything went smoothly as long as functional testing was required. We were ready to launch and somebody from SRE/Devops team asked: “Have you done load testing?” . Everything was superb up to this point where load testing results are required to make service live. Load Testing We started to put load to our services using apache benchmark. Very soon we realised our application is not scaling as much as we expected. To our surprise application was able to handle only 3 requ...

Allowing users to have ssh access Hi Readers, It is one of the tasks we need to complete in order to allow users to log-in into your server without compromising your security. We are going to accomplish the following tasks, 1.) Allow the users for given domain only 2.) Must allow access to a given domain 3.) Block access for a specific domain. These questions are asked in RedHat certification examination RHCE6 We are going to complete the above mention task using iptables To give proper example we are taking 192.168.20.0/255.255.255.0 as our domain and 192.168.21.0/255.255.255.0 as other domain. Assuming that your system is a fresh installation we can remove all rules previously applied. # iptables -F  The above mention command will flush all the previously applied rules. Insert a rule in your input chain by below mention command, # iptables -I INPUT -s <ip of your domain>/<subnet mask> -p <protocal tcp/udp> --dport <port> -...

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 sub Mail_Mailer { my $destination_directory = '/data/' ; my $from_address = "abc@gmail.com" ; my $to_address = "abc@gmail.com" ; my $subject = "SOFT DATA " ; my $body = "Dear Sir\nPlease find the complete set of data on sftp\n." ; my $cc = "test@gmail.com" ; opendir (DES, $destination_directory ); my @files = readdir (DES); close (DES); my @mail_sent_file = @file ; foreach my $mail_file_names ( @mail_sent_file ) { $body = $ {body} . "\n" . $mail_file_names . "\n" ; } $body = $ {body} . "\nRegards\nreportsadmin." ; my $mailer = Mail:: Mailer -> new ( "sendmail" ) or die ; $mailer -> open ( { From => $from_address , To => $t...

Start mysql in Ubuntu without having root privilege:- If you want to use mysql in Ubutu you can use following command which will use a root level privilege   $ mysql -u root -p Enter password: Welcome to the MySQL monitor.  Commands end with ; or \g. Your MySQL connection id is 147 Server version: 5.1.49-1ubuntu8.1-log (Ubuntu) When it demands to enter the password fill it with 'root' and hopefully you'll get logged in .   Last_insert_id():- (with no argument) returns the first automatically generated value that was set for an AUTO_INCREMENT column by the most recently executed INSERT statement to affect such a column. For example, after inserting a row that generates an AUTO_INCREMENT value, you can get the value like this:   mysql> SELECT LAST_INSERT_ID(); Database():- Database() method returns the current selected database and you can use it in your communication and your queries. The syntax is :   mysql>select Database (); User():- It a...