Closed. This question is opinion-based. It is not currently accepting answers.
Want to improve this question? Update the question so it can be answered with facts and citations by editing this post.
Closed 3 years ago.
Improve this question
Currently moving to Amazon EC2 from another VPS provider. We have your typical web server / database server needs. Web servers in front of our database servers. Database servers are not directly accessible from the Internet.
I am wondering if there is any reason to put these servers into an AWS Virtual Private Cloud (VPC) instead of just creating the instances and using security groups to firewall them off.
We are not doing anything fancy just a typical web app.
Any reason to use a VPC or not using a VPC?
Thanks.
NOTE: New accounts in AWS launch with a "default VPC" enabled immediately, and make "EC2-Classic" unavailable. As such, this question and answer makes less sense now than they did in August 2012. I'm leaving the answer as-is because it helps frame differences between "EC2-Classic" and the VPC product line. Please see Amazon's FAQ for more details.
Yes. If you're security conscious, a heavy CloudFormation user, or want complete control over autoscaling (as opposed to Beanstalk, which abstracts certain facets of it but still gives you complete access to the scaling parameters), use a VPC. This blog post does a great job summarizing both the pros and cons. Some highlights from the blog post (written by kiip.me):
What’s Wrong with EC2?
All nodes are internet addressable. This doesn’t make much sense for nodes which have no reason to exist on the global internet. For example: a database node should not have any public internet hostname/IP.
All nodes are on a shared network, and are addressable to each other. That means an EC2 node launched by a user “Bob” can access any of EC2 nodes launched by a user “Fred.” Note that by default, the security groups disallow this, but its quite easy to undo this protection, especially when using custom security groups.
No public vs private interface. Even if you wanted to disable all traffic on the public hostname, you can’t. At the network interface level each EC2 instance only has one network interface. Public hostnames and Elastic IPs are routed onto the “private” network.
What's Great About the VPC
First and foremost, VPC provides an incredible amount of security compared to EC2. Nodes launched within a VPC aren’t addressable via the global internet, by EC2, or by any other VPC. This doesn’t mean you can forget about security, but it provides a much saner starting point versus EC2. Additionally, it makes firewall rules much easier, since private nodes can simply say “allow any traffic from our private network.” Our time from launching a node to having a fully running web server has gone from 20 minutes down to around 5 minutes, solely due to the time saved in avoiding propagating firewall changes around.
DHCP option sets let you specify the domain name, DNS servers, NTP servers, etc. that new nodes will use when they’re launched within the VPC. This makes implementing custom DNS much easier. In EC2 you have to spin up a new node, modify DNS configuration, then restart networking services in order to gain the same effect. We run our own DNS server at Kiip for internal node resolution, and DHCP option sets make that painless (it just makes much more sense to type east-web-001 into your browser instead of 10.101.84.22).
And finally, VPC simply provides a much more realistic server environment. While VPC is a unique product to AWS and appears to “lock you in” to AWS, the model that VPC takes is more akin to if you decided to start running your own dedicated hardware. Having this knowledge beforehand and building up the real world experience surrounding it will be invaluable in case you need to move to your own hardware.
The post also lists some difficulties with the VPC, all of which more or less relate to routing: Getting an internet gateway or NAT instance out of the VPC, communicating between VPCs, setting up a VPN to your datacenter. These can be quite frustrating at times, and the learning curve isn't trivial. All the same, the security advantages alone are probably worth the move, and Amazon support (if you're willing to pay for it) is extremely helpful when it comes to VPC configuration.
Currently VPC has some useful advantages over EC2, such as:
multiple NICs per instance
multiple IP's per NIC
'deny'-rules in security-groups
DHCP options
predictable internal IP ranges
moving NICs and internal IPs between instances
VPN
Presumably Amazon will upgrade EC2 with some of those features as well, but currently they're VPC-only.
VPCs are useful if your app needs to access servers outside of EC2, e.g. if you have a common service that's hosted in your own physical data center and not accessible via the internet. If you're going to put all of your web and DB servers on EC2, there's no reason to use VPC.
Right now VPC is the only way to have internal load balancers
If you choose RDS to provide your database services, you can configure DB Security Groups to allow database connections from a given EC2 Security Groups, then even if you have dynamic IP addresses in your EC2 cluster, the RDS will automatically create the firewall rules to allow connections only from your instances, reducing the benefit of a VPS in this case.
VPS in the other hand is great when your EC2 instances have to access your local network, then you can establish a VPN connection between your VPS and your local network, controlling the IP range, sub networks, routes and outgoing firewall rules, which I think is not what you are looking for.
I would also highly recommend trying the Elastic Beanstalk, which will provide a console that makes easy to setup your EC2 cluster for PHP, Java and .Net applications, enabling Auto Scaling, Elastic Load Balancer and Automatic Application Versioning, allowing easy rollback from bad deployments.
You have raised a good concern here.
I would like to focus on the viability in terms of cost...
What about the cost factor?
I think You will be paying for that server per hour. Even if you pick $20-$50 dollars a month instance it will be something you will pay the rest of your server life. The VPN server is something you can easily set on old hardware very cheap and even free for open source solution.
Adding VPN to existing AWS servers park make sense, setting a solo VPN server on AWS doesn't. I don't think it is the best cost-effective option but that just my opinion.
Thanks,
Alisa
Related
I'm just looking for advice, I can do most of my own research, but I'm not sure where to start. Here's the situation:
I want to be able to deploy 3 vms that have 2 nic's a piece. 1 nic will have a standard IP that AWS provides. The second nic will have a pre-configured internal static IP. Let's say, 192.168.0.100, 101, and 102. That way each vm can talk to each other automatically without needing to know what the external IP is. The purpose of this is so that I can have a small cluster already configured and I won't have to do a lot of work every time I deploy the cluster.
I want this to be repeatable. Let's say I want this for a classroom. Each student has the identical set of clustered VMs. All they need to do is power them on and start working.
So, I think I can do this with Terreform. I don't know if AWS has it's own tooling that can do this also. If it has, I haven't been able to find it yet.
Any suggestions would be greatly appreciated!
In general, every VM gets a private IP, if the VM is public you can assign a public IP which makes the VM accessible from external and also provides internet access, this is be done by source/destination NAT.
https://docs.aws.amazon.com/vpc/latest/userguide/VPC_Internet_Gateway.html
As long as they are part of you VPC CIDR and available you can specify the IP addresses on instance launch. This can be done via AWS Console, API, CLI, CloudFormation and also with Terraform. The AWS native tools for doing it at scale / repeatable is CloudFormation or maybe also a script that runs AWS CLI commands would work.
https://awscli.amazonaws.com/v2/documentation/api/latest/reference/opsworks/create-instance.html
https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-ec2-network-interface-privateipspec.html
I'm working for a client that has a simple enough problem:
They have EC2s in two different Regions/VPCs that are hosting microservices. Up to this point all EC2s only needed to communicate with EC2 instances that were in the same subnet, but now we need to provision our infrastructure so that specific ec2s in VPC A's public subnet can call specific ec2s in VPC B's public subnet (and vice versa). Communications would be calling restful APIs over over HTTPS/TLS 2.0
This is nothing revolutionary but IT moves slowly and I want to create a Terraform proof of concept that:
Creates two VPCs
Creates a public subnet in each
Creates an EC2 in each
Installs httpd in the EC2 along with a Cert to use SSL/TLS
Creates the proper security groups so that only IPs associated with the specific instance can call the relevant service
There is no containerization at this client, just individual EC2s for each app with 1 or 2 backups to distribute the load. I'm working with terraform so I can submit different ideas to them for consideration, such as using VPC Peering, Elastic IPs, NAT Gateways, etc.
I can see how to use Terraform to make these infrastructural changes, but I'm not sure how to create EC2s that install a server that can use a temp cert to demonstrate HTTPS traffic. I see a tech called Packer, but was also thinking I should just create a custom AMI that does this.
What would the best solution be? This doesn't have to be production-ready so I'm favoring creating a fast stable proof-of-concept.
I would use the EC2 user_data option in Terraform to install httpd and create your SSL cert. Packer is great if you want to create AMIs to spin up, but since this is an POC and you are not doing any complex configuration that would take long to perform, I would just use user_data.
I want to use the Amazon Web Service free micro-instance for my different projects for testing and personal purpose. But I required some static-public IP on which I can run my server.
Is that possible? From where I can buy just IP and use it with my AWS?
EC2 Elastic IP Addresses
Elastic IPs are tied to an account, not an instance.
You need to look at AWS VPC for this.
Whilst VPC is free outside of the usual instance pricing, it doesn't work with Micro instances (the cheapest ones).
When not using VPC, you're assigned IP addresses through DHCP. When the DHCP lease expires, or you restart, your IP is released back to the pool.
VPC lets you use private IP addressing, you can use it with Elastic IPs and is much easier to integrate with a physical infrastructure setup.
If you're only testing/investigating AWS and have little or no budget to use anything other than a Micro instance, I'd just suck it up and deal with the changing of IPs.
If you've got a budget that lets you use instances other than Micro, then go for VPC.
Also, if you're doing more than testing/investigating I'd recommend starting with VPC straight away as trying to migrate from a non VPC to a VPC infrastructure is a massive PITA.
For every AWS account, 5 free elastic ips are provided. You have to just allocate them to required instance. But make sure that the allocate address(newly created elastic ip) in in use, because you will billed if the Elastic ip is not in use.
Looks like they have configured ARP statically so you can only use the IP address on an instance that was bound to that instance through the EC2 management console.
I just configured one of my instances to use a static IP address other than the one assigned through the management console and rebooted the instance.
I'm still receiving ARP responses on the old address but not receiving ARP responses on the new address at all.
Unfortunately for me, I have a not responding instance (NFS File Server) stuck in a stopping state while I attempt to terminate it.
The IP Address bound to that instance cannot be re-assigned to a replacement instance so now I have to reconfigure
On the whole pricing delima: When you come to think of it, there is a limited amount of static IPs so there must some pricing (supply and demand). This pricing is two fold: 1) for upto a limited number (5 per account) you don't have to pay. 2) if you created one you need to use it if you don't you'll be billed (to prevent every user to get 5 static IPs)
I sell a product that runs on Amazon EC2. A company now wants to purchase and install it within their perimeter... This also implies the use of a VPN connection to the EC2 datacenter.
I want to test my product using Amazon VPN (VPC) before handing over the code. Must I change my code to make it work across VPC? If I run on Windows, then wants the quickest and easiest desktop VPN client avaialable that will allow me to connect across VPN to the Amazon datacenter?
Make sure you setup NAT servers and set your routes in the AWS console. Your client can have some security infrastructure for extending their data center to the cloud - firewall rules at the VPC level etc. Disable firewall rules on the server you deploy to since your VPC already takes care of this. As root execute the following command. service iptables stop (you probably already know this I am guessing)
Is it important for your app to run across VPCs?
Depending on how large the company you are selling to is, their security team may give them the run around to have VPC to VPC communication. Is it important for your software to span across VPCs?
I'm trying to create a personal/professional website within a college-domain. From the university I've requested a static-IP address which is directed to a website-name "http://lastname.someuniversity.edu". I would like to setup an Amazon EC2 instance to host a website.
I know how to create/administer the website on the EC2 instance I just don't know how to get the EC2 instance to talk to the university (and vice-versa). The IT person at the university wasn't terribly helpful.
i know how to setup a local machine to run as the webserver just not how to get the Amazon EC2 instance to 'sit inside" the university.
Thanks for the help,
Will
If you want the Amazon EC2 instance "to sit inside your university" you may want to establish a VPN connection by using the Amazon Virtual Private Cloud service.
This service is still in beta, but it has been publicly available for about a year. A connection currently costs $0.05 per hour (circa $36.5 per month) and you also pay for data transfer.
Check out Amazon Virtual Private Clouds. I think it is exactly what you are asking for.
You will need to work with your "IT person" to setup a VPN connection between your premises and the EC2 cloud. In practice you will likely need to:
1) Define a subnet for your EC2 connections (ie. 10.10.10.x).
2) Build a VPN tunnel between your university and Amazon (Virtual Private Cloud).
3) Enable any routing or firewall changes at the university.
You know you've got it working when you can 'ping' the EC2 host from within your premises.
BTW, I have recently released a new service that specifically runs on Amazon EC2. About 20% of people are now asking for VPC in order to use our service (Virtual Lab Management), and so I can attest that it's a solution that has raised interest in a lot of large organizations.