For a group project in one of my university IT classes, each group is given 3 servers and the professor wants us to get an Apache CloudStack environment running using those three. While initially vague on instructions, he later informed us that we should install the ESXi hypervisor on all 3 of our servers and go from there.
We first installed ESXi on all 3 of our servers. Then we installed vCenter server on one of them in order to combine all the computing resources by adding each as a host in a cluster before we start setting up CloudStack. What we are about to do next is install the CloudStack Management server on a VM created in vCenter server.
I was reading the CloudStack documentation before we start the installation which is where my question stems from. The documentation mentions that a host should not have any running VMs on them before getting added to CloudStack. Here is the exact text:
Ideally clusters that will be managed by CloudStack should not contain any other VMs. Do not run the management server or vCenter on the cluster that is designated for CloudStack use. Create a separate cluster for use of CloudStack and make sure that they are no VMs in this cluster.
So my question is, does that include the management server VM? If it does, would that mean we have to make a separate cluster for just the host server that contains the management server? Cause if that's the case, we can't use any of the other resources on that server that is running the management server. Or does it mean that you can but it's just not recommended?
On top of that, the documentation also mentions the following:
Put all target ESXi hypervisors in dedicated clusters in a separate Datacenter in vCenter.
So would I have to put the ESXi host containing vCenter Server and CloudStack Management Server in both a separate datacenter and cluster?
I am new to Vmware APIs, is there some way to use Rest/Soap APIs to deploy a VM on a given IP of either an ESXi Server or a Vcentre Server?
I know there exists CreateVM_Task in VSphere Web Services SDK but how to use it for an ESXi Server on a remote location?
Theoretically, you run the sample the exact same way. However you authenticate to the ESXi host directly instead of the vCenter server.
Now that I think about it, you'll probably also have to remove the datacenter parameter since hosts don't contain datacenter objects.
I installed FREEIPA on ubuntu 16 and set the hostname and update the /etc/hosts file as well, and Installed FREEIPA successfully but could not able to access "https://ipa.example.com" on the browser.
Note:-
This VM is on the Google Platform and part of private DNS
error:-DNS_PROBE_FINISHED_NXDOMAIN
If you're using freeipa you are probably going to authenticate multiple machines against it.
Modifying /etc/hosts is a temporary solution that's not going to work on large environment: you need a dns server to answer when a server asks for ipa.example.com moreover you need dns to manage priority between multiple ipa servers if need high availability and resilience.
What are the exact differences between EC2, Beanstalk and LightSail in AWS?
What are good real time scenarios in which I should use these services?
They are all based on EC2, the compute service from AWS allowing you to create EC2 instances (virtual machines in the cloud).
Lightsail is packaged in a similar way than Virtual Private Server, making it easy for anyone to start with their own server. It has a simplified management console and many options are tuned with default values that maximize availability and security.
Elastic Beanstalk is a service for application developers that provisions an EC2 instance and a load balancer automatically. It creates the EC2 instance, it installs an execution environment on these machines and will deploy your application for you (Elastic Beanstalk support Java, Node, Python, Docker and many others)
Behind the scenes, Elastic Beanstalk creates regular EC2 instances that you will see in your AWS Console.
And EC2 is the bare service that allows the other to be possible. If you choose to create an EC2 instance, you will have to choose your operating system, manage your ssh key, install your application runtime and configure security settings by yourself. You have full control of that virtual machine.
In simple terms:
EC2 - virtual host or an image. which you can use it to install apps and have a machine to do whatever you like.
Lightsail - is similar but more user friendly management option and good for small applications.
Beanstalk - an orchestration tool, which does all the work to create an EC2, install application, software and give you freedom from manual tasks in creating an environment.
More details at - https://stackshare.io/stackups/amazon-ec2-vs-amazon-lightsail-vs-aws-elastic-beanstalk
I don't know if my scenario is typical in any way, but here are the differences that were critical for me. I'm happier EC2 than EB:
EC2:
just a remote linux machine with shell (command line) access
tracable application-level errors, easy to see what is wrong with your application
you can use AWS web console panel or AWS command line tool to manage
you will need repeated steps if you want to reproduce same environment
some effort to get proper shell access (eg fix security rule to your IP only)
no load balancer provided by default
Elastic Beanstalk
a service that creates a EC2 instance with a programming language of your choice (eg Python, PHP, etc)
runs one application on that machine (for python - application.py)
upload applications as .zip file, extra effort needed to use your git source
need to get used to environment vs applications mental model
application level errors hidden deep in the server logs, logs downloaded in separate menu
can be managed by web console, but also needs another CLI tool in addition to AWS CLI (you end up installing two CLI tools)
provides load balancer and other server-level services, takes away the manual setup part
great for scaling stable appications, not so much for trial-and-see experimentaion
probably more expensive than just an EC2 instance
Amazon EC2 is a virtual host, in other words, it is a server where you can SSH configure your application, install dependencies and so on, like in your local machine. EC2 has a dozen of AMI (Amazon Machine Image: it is some kind of operating system of your EC2 server, for instance, you can have EC2 running on Linux based OS or in windows OS). To summarize, it is a great idea if you need a machine in your hands.
Amazon Lightsail is a simple tool that you can deploy and manage application with small management of servers. You can find it very practical if your application is small, For instance, it will perfectly fit your application if you use Wordpress or other CMS.
AWS Elastic Beanstalk is an orchestration tool. You can manage your application within that service, it is more elevated then AWS Light Sail.
If you still do not understand the differences, you can take a look at each service overview.
There is also an answer in Quora
I have spent only 10 mins on these technologies but here is my first take.
EC2 - a baremetal service. It gives you a server with an OS. That is it. There is nothing else installed on it. So if you need a webserver (nginx) or python, you'll need to do it yourself.
Beanstalk - helps you deploy your applications. Say you have a python/flask application which you want to run on a server. Traditionally you'll have to build the app, move the deployable package to another machine where a web server should be installed, then move the package into some directory in the web server. Beanstalk does all this for you automatically.
LightSail - I haven't tried it but it seem to be an even simpler option to create a server with pre-installed os/software.
In summary, these seem to make application deployment more easier by pre-configuring the server/EC2s with the required software packages and security policies (eg. port nos. etc.).
I am not an expert so I could be wrong.
When connecting to my AWS RDS from my AWS machine it works great, but when trying to connect from my local machine - it takes a lot of time.
It is slow when executing some queries(for some it takes longer than others).
Slow means more than 5 seconds for a query that takes less than 1 second on my production server.
My production server & RDS are in N.virginia (USA) while I am in Israel.
When uploading my project to the production server it works fast (less than a second for the query), but when working from my local network it takes more than 5 seconds!
I was looking for an answer all over the web with no success.
For local development consider setting up a development database on your workstation. You can install the database on your machine for development and configure your project to connect to it instead of production. This is generally a considered a best practice anyway.
Another consideration is to setup a database closer to your region. Check this page for services in your area.