We are moving from one server architecture to two servers, web and DB.
The two new servers are VMs on one physical box. The VMs have a private virtual network setup so they can talk to each other directly with local IP without going through any other switches in the data center but their virtual switch. Pinging one VM from the other is less < 1ms.
We have two applications running on these servers, one is built in c#.NET and the other one is in PHP.
.NET application has no issues with the two VMs setup.
PHP, however, has a latency of about 400ms more compared to the application running on a server with application and db residing on that server.
To make sure the queries in the db are not a problem, we installed the application on the db VM to run it locally, and it was running at the same speed as on our previous server. So queries are not a problem.
Any ideas what could be causing the issue???
I have started making a website and was hosting on Hostgator but I am going to move it to Amazon web services before launch. There is a small problem that I previously just uploaded my files to the relevant location to Hostgator and it has all just worked. I have no experience in setting up from scratch a production worthy server setup and I need to know how. I did setup the basic lamp stack on the EC2 instance, however, I keep reading that when the EC2 instance does down it will take all the data with it and I can not have that happen. I have also read then when it dies it wont do anything and you have to start up the apache server again it is not automatic. I need it to be reliable and have the data independent so it will not crash, burn and die if the server goes. I have worked out that I will need S3 for static things such as my PDF's and images as well as using the RDS for my MYSQL database. My domain name is registered elsewhere so I believe I need to use route 53 as well.I want to use AWS for a few reasons reasons, firstly as it can scale which is really important but not sure if this is built in or it requires customization. I have been told that it is very secure the EC2 and the last reason is that I can debug my php code. The debug reason is that I have an error that only appears on the Hostgator server not my local lamp stack and I can't debug it there so I should be able to when I move to EC2.
I have done a lot of looking around online and I can't find anything comprehensive about what to setup. I have been reading (some of you may think otherwise). However, I am so overwhelmed by the amount of information there is as it is either far to complicated discussing some theory that I do not care about or to easy and does not discuss how to use anything other then a generic install of a LAMP stack on the EC2 with out using the other services.
I have seen http://bitnami.com/stack/lamp/cloud/amazon but do not think this is what I want as again the EC2 has a mysql database and I am not using the RDS
If someone can point me in the direction of a comprehensive guide to setting up a slid LAMP stack on AWS (mabey even a book has been written) that would be great as I found the amazon docs did not go into much detail and told me how to do things but not why I should do them and what purpose they had.
Thanks
I'll start with answering your q's first, and as you are a newbie I would suggest don't pressurize to learn all of AWS, you can keep migrating slowly and keep discovering the magic of cloud.
Q.
when the EC2 instance does down it will take all the data with it and
I can not have that happen. I have also read then when it dies it wont
do anything and you have to start up the apache server again it is not
automatic?
A. When an EC2 instance goes down (down could mean shutdown manual by you or Down means AWS network is down, or instances are having some other issues) only the data on "ephemeral data" or you can say data on RAM or sessions will get lost, whatever is on disk will remain on disk, And the instance will be available as soon as problem is resolved.
Apache will start itself when an instance restarts, and remains up until you manually shut it down or some other issue.
Q. I will need S3 for static things such as my PDF's and images as
well as using the RDS for my MYSQL database?
A. Its a good practice to keep static stuff on s3, but not a necessary thing to do, you can set up a ftp or manage your static content like you were used to, like keeping it on a folder of your website.
You don't necessarily need RDS to have a mysql database, I have a process running on aws with around 40 mil transactions a day, and I do it on a normal mysql at an ec2 instance.
however having RDS gets rid from the daily backup and index maintenance hustles.
Q. My domain name is registered elsewhere so I believe I need to use
route 53 as well ?
A. Again not a necessary thing, you can just go to your domain manager and change the A-name or C-name records (with static public ip of ec2) and give a static public ip to your ec2 instance or Elastic load balancer and you'll be up and running in no time.
Q. I want to use AWS for a few reasons reasons, firstly as it can
scale which is really important but not sure if this is built in or it
requires customization.
A. It can scale really well, but depends how do you want it to scale, and its highly customizable.
there are 2 kinds of scaling
vertical - you change your instance type from one type to another to get better disk / cpu or RAM or better network performance, but this will need you to stop your ec2 instance and change its type, that means there will be downtime of around 10 minutes while you do so.
horizontal - you can put your website (ec2 based) behind a load balancer (ELB - elastic load balancer) and add/remove more instances to/from it as and when you deemed suitable, or you can also have an auto scaling policy to help you do it automatically depending up on the load at your web server.
Security? - you can be very well assured its very well secure, and so much secure that I can bet my life on a secure ec2 instance, i can swear by linux thor that it works and it works like a charm.
Debugging? - I suggest you do debugging by classic means, make logs of errors and all, just treat ec2 like a normal machine and learn slowly the tricks of trade.
Now lets setup a basic solid LAMP stack for ourselves, I am assuming that you have a ready ubuntu instance, and you can ssh to it, in case you haven't been able to make one - see this.
basically.
1. create security groups - This is your firewall, makes sure which ports are open, and also makes sure which ec2 instances can talk amongst themselves.
2. Create an ec2 instance - make any ubuntu instance.
And access your instance using ssh - ssh is basically secure terminal connection to your ec2 machine which is secured by a key file (pem file) and whoever has it can access your machine's data, so keep it very very secure, and you can't afford to lose it.
3. install LAMP using - Tasksel utility
4. setup a public ip for yourself ( costs a dollar per month) - you can use this ip to redirect your www.example.com traffic using domain manager of your DNS provider - godaddy or someone alike i suppose.
I think this will be it to make you start with AWS.
Just to be safe that you have a copy of your data make an AMI of your ec2 instance with all the data on it. AMI is the image from which you can make a similar or better instance in 10 minutes flat (or even lesser).
You wil pay for - instance type you chose, public IP, traffic if its beyond a level (usually very very cheap), and disk usage (8 gb is the default disk), and AMI volume.
Have fun with AWS.
To retain data between during the down time, make sure you use EBS storage. Its default now a days. In the past, before EBS, instance storage was default and you would lose data once server is down, but with the EBS storage, data is retained during the shutdown.
You can go one of the follow two routes depending upon your needs.
1. Use AWS ElasticBeanStalk (http://aws.amazon.com/elasticbeanstalk/) if you do not need to install anything additional Its super easy and its similar to Google Apps and you can deploy your app quickly. You do not get server, but a server to deploy your app. You have to use RDS for database and S3 for storage. You can not store locally on the server where you are running.
Use EC2 server with static IP address. You can get pre-configured LAMP stacks from market place. I use bitnami cloud stacks for AWS that comes pre-configured with LAMP and many other apps. Just use their free account to create micro instance for your PHP and select a server and you are good to go. http://bitnami.com/cloud
You do not need to use Route 53 unless you need to manage DNS programatically. You can just point your server to EC2 server by adding entry in your DNS (godaddy or whoever is your domain name provider).
Bitnami service also allow scheduled backups, but if you are not storing anything locally, you do not need frequent backups.
Make sure you use Multi-AZ option in RDS which is more reliable. When you provision a Multi-AZ DB Instance, Amazon RDS automatically creates a primary DB Instance and synchronously replicates the data to a standby instance in a different Availability Zone (AZ). Also, Amazon RDS automatically patches the database software and backs up your database, storing the backups for a user-defined retention period and enabling point-in-time recovery, up to last 5 minutes.
I hope this helps.
You should be using dynamo DB (http://aws.amazon.com/dynamodb/pricing/) in with LAMP without Mysql for storage. Having a Samebox database can almost never give you reliability. So you will not loose your data what ever your Application box goes through. You can even read our application config from dynamo DB.
http://aws.amazon.com/documentation/dynamodb/
http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/SettingUpTestingSDKPHP.html
Do I need to use EC2 with DynamoDB?
You wont loose data when server is down. Just make sure your select EBS volume, and not Instance.
You can get ready-made server from AWS market place. I used the following for my projects, but there are many other pre-configured servers available.
https://aws.amazon.com/marketplace/pp/B007IN7GJA/ref=srh_res_product_title?ie=UTF8&sr=0-2&qid=1382655655469
This with RDS server is what you need. We use this all the time for production servers and never had any issues.
Here are two guides that look good to me:
http://shout.setfive.com/2013/04/05/amazon-aws-ec2-lamp-quickstart-guide-5-steps-in-10-minutes/
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/install-LAMP.html
If learning the Linux command line isn't your thing, you should consider going "up the stack" to a PaaS (Platform As A Service). They are things like Heroku, Google App Engine, and ElasticBeanStalk.
The trade-off between Infrastructure as a Service (IaaS like EC2) and a Platform as a Service (PaaS like Heroku):
- PasS is quicker to get started, less to learn. IaaS requires you to know the entire stack from the start (or hire/rent a sysadmin).
- PasS usually gets more expensive as you get bigger compared to IaaS (but it depends).
- PaaS has less control (you can't choose the language version, so you can't upgrade to get around a specific bug.)
- IaaS can literally do anything (it's just a Linux box)
- IaaS allows for more tuning (upgrade libraries to get features, switch to different instance type to trade off RAM for CPU, run HipHop for speed, add caching layers, etc)
You have a few choices:
Use only EC2. Install Apache+MySQL and your dynamic website on EC2. This will be very similar to setting it up on Hostgator except you are running a full server.
Use EC2 for "compute" (that is, the dynamic part of the site) and S3 for storage. This doesn't differ much from #1 above, except that you are using S3 for static file storage - which is great if you are expecting to host a lot of static content (multimedia, etc)
Set up your website using Amazon Elastic Beanstalk (which now supports PHP). However, if you go this route, you will need to host your database somewhere - which will likely be RDS.
I recommend going with #1. There is nothing wrong with that - yes, if EC2 goes down, it will take down your site with it, but to alleviate that, you can run two servers in two different regions (one in US East and one in US West) - I don't think two EC2 regions have ever gone down at the same time.
UPDATE: If you are concerned about backup/restore and making sure your data is safe, I recommend the following (I do this with a site in production on EC2):
Put your website code into Git/SVN source control; and pull from there
Backup your MySQL database to Amazon S3 regularly (at least once a day) using mysqldump
I think you have some misconceptions.
If EC2 as a whole goes down (which is rare) then you do NOT lose your data. The site would simply be offline until Amazon restored services.
If your particular instance goes down due to a hardware issue, then you might lose data. This is no different than if your own server went belly up. The right answer is to simply make normal backups of your database and store it in S3 or some other location. Generally you will want to create and attach a second EBS volume to your DB server which has the DB files on it as well.
If you Terminate your instance then, yes you will lose everything on that. However Amazon has the ability to make terminating instances difficult so you don't do it accidentally.
Stopping your instance is like turning the computer off. The difference being that you can remotely turn it back on when you want. You can only stop EBS backed instances - which means that your data is safe while it is offline.
I would highly suggest that if you are uncomfortable with setting up and maintaining your own server that you should investigate fully managed hosting instead. EC2 is awesome, we've been on it for 2 years. However, we have a strong tech team that understands what it takes to run and manage servers.
I'm using Rackspace Cloud Servers. I have installed NGINX with PHP and Memcache.
When the Web server is approaching capacity, I plan to clone the server, and then add a load balancer on top of it i.e. two servers with one load balancer managing the traffic between the two. All this is done automatically using the Rackspace API.
However, I'm lost as to what is going to happen to Memcache. I now have two Memcache servers. So the cache will no longer work as expected being that there are now, essentially, two Memcache servers.
Is it possible to just install Memcache on a unique server and then have my main Web server access it, this way when I want to create a situation where there is a load-balancer i.e. two web servers, they would both be referencing the same Memcache server?
Yes, you can have a single Memcached server and all Memcache clients connect and use it (rather than local installs of Memcached). You can use two Memcached servers if the data inconsistency is acceptable and the cost of calculating any stored data twice is acceptable to you. It'll save you time in the short-term, but ultimately it will probably complicate things.
In relation to Rackspace, make sure you're using the private direct IP address Rackspace gives you to network across machines instead of the external WAN IP. This will be faster, more secure, and won't count against your bandwidth allocation.
We have our database servers separate from our webserver. The database servers are replicated (we know there is overhead here). Even with replication turned off however, performance for large number of queries in a PHP script is 4 times slower than our staging server that has the db and apache on the same machine. I realize that network latency and other issues with a network mean that there is no way they will be equal, but our productions servers are exponentially more powerful and our production network is all on gigabit switches. We have tuned MYSQL as best as we can but the performance marker is still at 4x slower. We are running over nginx with Apache proxies and replicated MYSQL dbs. UCarp is also running. What are some suggestions for areas to look for improving the performance? I would be happy with twice as slow on production.
It's difficult to do much more than stab in the dark given your description, but here's some starting points to try independently, which will hopefully narrow down the cause:
Move your staging DB to another host
Add your staging host to the production pool and remove the others
Profile your PHP script to ensure it's the queries causing the delay
Use an individual MySQL server rather than via your load balancer
Measure a single query to the production pool and the staging server from the MySQL client
Run netperf between your web server and your DB cluster
Profile the web server with [gb]prof
Profile a MySQL server receiving the query with [gb]prof
If none of these illuminate anything other than the expected degradation due to the remote host, then please provide a reproducible test case and your full MySQL config (with sensitive data redacted.) That will help someone more skilled in MySQL assist you ;)
Not every web request on a web site will (if properly designed) need a mysql connection. Most likely, if you are requiring a connection on every http request, your application will not scale and will start having issues very quickly.
Do more caching at app. server to request mysql less often. E.g. use
memcache.
Try to use persistent connections from application to your mysql servers.
Use mysql data compression.
Minify data (limit your selects, use column names instead of "*" in select statements)
Shamanic tuning:
Make sure, that nothing slows down network at mysql servers: big firewall rulesets, network filters, etc.
Add another (client inaccesible) network interface for app. server
and mysql server.
Tune network connection between app. server and mysql. Sometimes you
can win several ms by creating hardcoded network routes.
Don't think any of above would help - if network connection is slow, nothing of above will significantly speed it up.
I am currently planing a web application and I want to plan it to eventually run on a cluster later.
The cluster would be made of a php web cluster and a mysql cluster and a standalone storage unit (maybe a cluster of it I really don't know how that works :s)
I want to know if the code will be different than when php and mysql are on the same machine and what would be different?
The fact that the web and database servers are on different physical machines wouldn't change your code at all. The only place you'd need to change code is where you connect to the database - replacing the localhost reference with the IP address or hostname of the database server.
A clustered web server may need a different approach for storing sessions. If you got multiple webservers behind a load balancer, consequitive requests from the same session may end up on different servers. You should store the session data in a different place, like a central memcache.
Apart from a few of those issues, you should be fine regarding the web server.
As far as I know, MySQL and clustering are no friends. Although I wasn't really involved in the process, I know there has been a lot of trouble to get two database servers run together in our environment and even now they are not really clustered. They syncronize, but only one is actively used while the other is a fallback server.