Category Archives: Bash - Page 2

Mail 550 filter

Posted by on September 25, 2013 No comments

If you make a project with huge amount of email notification, you MUST control number of 550 reply from mail servers. Because if you skip this step, and continue sending to deleted mail boxes, big mail providers such as gmail.com, mail.ru, mail.ua, etc. will ban you domain at 0.5 – 1% “user unknown” reply.
So mail.log parsing is only solution.
In our project we add bad email addresses to database table (we use postgress)

1. make database replace rule, if email already added, (email is primary key) it is fastest way to prevent errors on INSERT duplicate email addresses.
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How to capture bad email addresses in mass mail.

Posted by on April 16, 2013 No comments

We have huge project with a great number of registered users. They receive notification via email, when actions occur. (new comment, gift, some other activity). Project targeting – Russia and former USSR In Russia some free email hosting providers like mail.ru delete user account after 2-3 years of inactivity.
So we have now 2-3000000 users with bad email address.
How to find them and remove from mailing list:

According to RFC 5321 (smtp rfc) in case of wrong email in rcpt to, server should return 550 no such user.
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Mysql check auto_increment values

Posted by on January 10, 2013 No comments

We get old project, with braindead architecture.
Database structure provides surprises regularly. Yesterday we had a problem with maximum integer value reached at one column.

‘id’ at one table was auto_increment and “INT” not UNSIGNED INT or BIG INT, so after reaching id value 2147483647 application stop working, I change type to UNSIGNED BIGINT.

ALTER TABLE ad_campaigns_rates MODIFY id BIGINT UNSIGNED  not null auto_increment, AUTO_INCREMENT = 2147483648;

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How to check if zabbix agent insstalled at all infrastructure hosts

Posted by on October 2, 2012 No comments

We use LXC containers at PH hosts.
containers named like:
rolename$RoleVersion-$InstanceNumber

For example
at host sXX2
appserver1-1
db1-1
db1-2
zabbix3-1

We need to check, if zabbix agents are installed at all infrastructure. One way – user fabric, Luke, as all 80 level DevOps do, or use ssh as all 40 level DevOps do.
Sorry for a little bit 🙂 “hindi” code 🙂 no review was done 🙂
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How to install unassigned packages ubuntu/debian

Posted by on October 1, 2012 No comments

We start chef deployment…
Chef deserve additional Huge article, but let`s start:

  echo "deb http://apt.opscode.com/ `lsb_release -cs`-0.10 main" | sudo tee /etc/apt/sources.list.d/opscode.list
  aptitude update
  aptitude -o Aptitude::CmdLine::Ignore-Trust-Violations=true install opscode-keyring
  aptitude -y -o Aptitude::CmdLine::Ignore-Trust-Violations=true install chef