PHP.TO.START 2013 - Scalabilità ed alta disponibilità con PHP e sistemi cloud

Durante il corso della presentazione sarà mostrato come realizzare un'infrastruttura scalabile che ruoti intorno a PHP come strumento centrale di business col fine di realizzare un'infrastruttura distribuita geograficamente che permetta scalabilità ed alta disponibilità grazie alle nuove tecnologie di Cloud Computing. La presentazione prevede di far capire l'intero processo di deploy e come il PHP è fondamentale per restare agili nonostante un'infrastruttura complessa.

1. PHP & Cloud Computing PHPTOSTART 2013 Walter Dal Mut - @walterdalmut - @corleycloud
2. Whoami • Walter Dal Mut • Startupper • Corley S.r.l. • http://www.corley.it/ • UpCloo Ltd. • http://www.upcloo.com/ • Electronic Engineer • Polytechnic of Turin • Social • @walterdalmut - @corleycloud - @upcloo • Websites • walterdalmut.com – corley.it – upcloo.com Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo • Corley S.r.l. • Scalable CMS • www.xitecms.it • Load and Stress tests • www.corley.it • Consultancy • PHP • AWS • Distributed Systems • Scalable Systems
3. AWS - Application Management Solutions Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
4. Why scalability Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo Source Jeff Barr AWS slideshare.net/…
5. Also daily… Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
6. Provision with fixed hardware Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
7. Thanks to Cloud Computing Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
8. Are you wasting monies? Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
9. Scalability effects on your business • Scale capacity on demand • Turn fixed costs into variable costs • Always available • Rock-solid reliability • Cost-effective • Reduce time to market • Focus on product and core competencies Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
10. Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
11. Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
12. Scalable PHP environments – Initial Step Web Instance MySQL 89.30.31.32/32 Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
13. Scalable PHP environments – autoscaling Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo Elastic Load Balancer Web Instance MySQL
14. Scalable PHP environments – autoscaling Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo Elastic Load Balancer Web Instance MySQL Web Instance
15. Scalable PHP environments – autoscaling Elastic Load Balancer Web Instance MySQL Web Instance Web Instance MySQL Read Replica Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
16. AWS (Elastic) Load Balancer • You can distribute incoming traffic across your web instances • When it detects unhealthy load-balanced web instances, it no longer routes traffic to those web instances and spreads the load across the remaining healthy web instances. • Elastic? • automatically scales its request handling capacity in response to incoming application traffic. Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
17. Autoscaling • Scale out web instances seamlessly and automatically when demand increases • Replace unhealthy or unreachable instances to maintain higher availability of your applications. • Scale dynamically based on your Cloud Watch metrics, or predictably according to a schedule that you define.. • Run on-demand or spot instances Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
18. Metrics and Autoscaling EC2 Instance CloudWatch Autoscaling Scaling rules Elastic Load Balancer Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
19. Metrics and Autoscaling Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo EC2 Instance CloudWatch Autoscaling Scaling rules Alarms Elastic Load Balancer EC2 Instance
20. Metrics and Autoscaling Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo EC2 Instance CloudWatch Autoscaling Scaling rules Elastic Load Balancer EC2 Instance
21. Metrics and Autoscaling Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo EC2 Instance CloudWatch Autoscaling Scaling rules Alarms Elastic Load Balancer EC2 Instance
22. Metrics and Autoscaling Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo EC2 Instance CloudWatch Autoscaling Scaling rules Elastic Load Balancer
23. Scale with metrics, scheduled or both? • How to scale? It depends by your application • Scheduled scale operations are useful when you have predictable spikes • Metrics when you have heavy spike application and you need to adjust your infrastructure automatically • Mix previous in mixed scenarios • Which metric use in order to scale? • It depends by your application design • CPU heavy scale on CPU load metric • Network heavy scale on network load metric • Etc. • Remember that applications don’t consume only CPU but also other resources Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
24. We have to discuss about: • Session Management • If we open and close servers runtime we have to maintain PHP sessions in order to handle user logins and other application features related to the end user session. • Database connections • All MySQL connectors (PDO, MySQLi, [mysql_*]) handle just one connection… No “x” RDB connection at the same time • Software maintenance • How we can ran the same application version on all our infrastructure? • What about logs? How we can collect VM logs in order to centralize the log management? Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
25. Session Management • Fortunately with PHP you can use different strategies to centralize sessions • Memcache/Memcached (AWS ElastiCache) • Redis • DynamoDB (AWS) • Etc. • We can modify the session_handler in order to use a different storage (php.ini, your application bootstrap, etc.) session.save_handler = memcache session.save_path = “tcp://1.cache.group.domain.tld:11211” Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
26. MySQL – Master/Slave? • Master/Slave is a model of communication where one device or process has unidirectional control over one or more other devices • MySQL can scales out all your read (SELECT) operations on different slave servers. • AWS RDS (Relational Database Service) helps you to create read replicas directly in AWS web console with a couple of clicks! Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
27. PHP Application MySQL READ Replicas MASTER SLAVE 1 SLAVE 2 Application SELECT ONLY SELECT ONLY INSERT/UPDATE/ DELETE/SELECT Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
28. Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
29. Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
30. Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
31. MySQL Native Driver • MySQL native driver? • Available from PHP >= 5.3 • You have to compile your PHP with “mysqlnd” support • --with-mysqli=mysqlnd --with-pdo=mysqlnd --with-mysql=mysqlnd • Delegate to “mysqlnd_ms” the master/slave management • http://php.net/manual/en/book.mysqlnd.php Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
32. Create the mysqlnd_ms configuration file { "myapp": { "master": { "master_0": { "host": "localhost", "port": "3306" } }, "slave": { "slave_0": { "host": "192.168.2.27", "port": "3306" } } } } The simple JSON configuration is divided in two main section • Master • Slaves “myapp” is the hostname that we use instead the real mysql host address. Eg. • mysql_connect(“myapp”, “user”, “passwd”); • new Mysqli(“myapp”, “user”, “passwd”); • new PDO(“mysql:dbname=testdb;host=my app”); Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
33. Maintain softwares Elastic Load Balancer Web Instance Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
34. Maintain softwares Elastic Load Balancer Web Instance Web Instance Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
35. Maintain softwares Elastic Load Balancer Web Instance Web Instance Web Instance Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
36. Maintain softwares Elastic Load Balancer Web Instance Web Instance Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
37. Maintain softwares Elastic Load Balancer Web Instance Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
38. How we can stay fresh? • If servers starts and stops continuously we have to find solutions to stay updated also on software • When a server starts, it has to create a valid environment in order to provides web pages. Strategies? • Compile and bundle all softwares in one instance image • It is very simple but all software becomes old very quickly and when you have to release an update you have to compile a new image and update all load balancers configurations. It is a long and complex operation • Use EC2_USER_DATA feature provided by AWS • You can run a shell script when your instances bootstraps. It is more flexible because you can create a skeleton (PHP + libraries) and download all software runtime during the boot operation • Typically you will use both in conjunction Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
39. Cool Up/Down – Inhibits alarms Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
40. Scales in action Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
41. Run commands on multiple servers • If you ran many servers execute commands could be hard. You can use tools to run commands on a server list • Capistrano (Ruby) • https://github.com/capistrano/capistrano • Fabric (Python) • https://github.com/fabric/fabric • Use CLOTH for AWS EC2 instances • https://github.com/garethr/cloth • Chef • Puppet • Etc… Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
42. Fabric is very simple #! /usr/bin/env python from __future__ import with_statement from fabric.api import * from fabric.contrib.console import confirm from cloth.tasks import * env.user = "root" env.directory = '/mnt/wordpress' env.key_filename = ['/home/walter/Amazon/wp- cms.pem'] @task def reload(): "Reload Apache configuration" run('/etc/init.d/apache2 reload') @task def tail(): "Tail Apache logs" run('tail /var/log/syslog') EC2 instances are dynamic with don’t know addresses, for that reason we can use tagging system to execute commands on a group of instances fab nodes:"^production.*" tail Execute the “tail” command on all instances with a name that starts with “production.” Eg. • production.web-1 • production.log • production.mongodb Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
43. Centralize all logs • We create and destroy instances thanks to alarms but when we close an instance we lose immediately all instance/application logs • How we can manage logs? • The simplest way is to use Rsyslog clusters • Rsyslog is an opensource software that forwarding log messages in an IP network • Rsyslog implement the basic syslog protol • That means that we can configure apache logs to “syslog” instead using normal text files. • In this way we can collect all logs in one group of VM and work on these files later thanks to other technologies Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
44. Log management • Collecting logs is not the latest operation because you have to analyse and reduce information • Move logs to S3 bucket – Time based • Analyze logs with Hadoop • Map Reduce on the cloud with Elastic Map Reduce service (EMR) • Use script languages on top of Hadoop in order to simply the log analysis • HIVE – Data Warehouse infrastructure (data summarization) • Pig – High level platform for creating MapReduce program Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
45. Cloud Conference 2013 – 18 April • www.cloudconf.it • @_CloudConf_ • https://www.facebook.com/pages/Cloud-Conf-Italia/140265592804313?ref=hl • Data analysis • Hadoop – MapReduce Framework • Apache Pig – MapReduce Scripting Language for Hadoop • Apache Hive – Data Warehouse System for Hadoop PUG User Coupon Code: pug-user Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo
46. Thanks for listening Any questions? Walter Dal Mut walter.dalmut@gmail.com @walterdalmut @corleycloud @upcloo