Amazon Elastic Compute Cloud (EC2) provides self-service, on-demand, pay-for-what-you-use computing infrastructure resources.

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105
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Why do I get “Permission denied (publickey)” when trying to SSH from local Ubuntu to a Amazon EC2 server?

I have an instance of an application running in the cloud on Amazon EC2 instance, and I need to connect it from my local Ubuntu. It works fine on one of local ubuntu and also laptop. I got message ...
72
votes
4answers
12k views

Why is TCP accept() performance so bad under Xen?

The rate at which my server can accept() new incoming TCP connections is really bad under Xen. The same test on bare metal hardware shows 3-5x speed ups. How come this is so bad under Xen? Can you ...
61
votes
5answers
37k views

How to change an EC2 instance's security group

I have created a new EC2 instance. It got assigned the default security group. I want to change that security group. How?
44
votes
2answers
9k views

Amazon EC2 terminology - AMI vs. EBS vs. Snapshot vs. Volume

I have been poking around Amazon EC2, and am a little confused on some of the terminology. Specifically with regard to AMI, snapshots and volumes, and an EBS Please correct me if I am wrong, or fill ...
43
votes
3answers
47k views

How to delete Instances in Amazon EC2 ? Change Pair Key?

How to remove Instances ? I test some Instances and now I terminate it. So, I want to remove it. I can't find delete or remove action. I just found terminate. How to change the pair key ? I don't ...
35
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4answers
13k views

Why don't EC2 ubuntu images have swap?

I started a couple servers on EC2 and they don't have swap. Am I doing something wrong or is it that the machines just don't have any?
30
votes
6answers
18k views

How to add a security group to a running EC2 Instance?

I have an Amazon EC2 instance running and I will like to add another security group to that instance and then remove the current security group from that instance. Is this possible?
29
votes
3answers
18k views

What's best practice for communication between Amazon EC2 instances?

I've been setting up Amazon EC2 instances for an upcoming project. They are all micro instances, running Ubuntu Server 64bit. Here's what I've setup so far: Web Server -- Apache Database Server ...
29
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8answers
4k views

How are admins managing their EC2 EBS's and Snapshots?

My company is moving our hosting to Amazon and I'm working though all the migration issues. It has been quite a challenge transitioning from physical hardware to transient virtual machines. One of ...
27
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3answers
13k views

Do I need to run ntpd in my EC2 instance?

I'm working on getting some servers running in the EC2 environment and I'm noticing some errors with ntpd trying to sync (using CentOS). I was reading on this site and the impression I get is that I ...
23
votes
1answer
10k views

EC2: is an instance's public DNS stable? Can I rely on it not changing?

I'm new to Amazon EC2. I've launched my first instance, and am using it as a web server. I see that it has a public DNS (a public URL), e.g.: ec2-123-45-6-789.compute-1.amazonaws.com I can ...
22
votes
5answers
2k views

Amazon EC2 Data Persistence

According to the Amazon EC2 FAQ, when an instance is terminated the data is gone. What steps can I take to preserve data in the event my instance is rebooted? I've been looking into EBS and S3 - would ...
21
votes
1answer
3k views

Python CGI on Amazon AWS EC2 micro-instance — a how-to!

How can you make an EC2 micro instance serve CGI scripts from lighthttpd? For instance Python CGI? Well, it took half a day, but I have gotten Python cgi running on a free Amazon AWS EC2 ...
19
votes
6answers
16k views

Amazon Linux vs. Ubuntu for Amazon EC2

I'm setting up my first website on Amazon EC2, and I'm trying to decide which distro to use. I've used Redhat and CentOS in the past, but I have no bias towards any system, I just want to use whatever ...
18
votes
4answers
19k views

How can I prevent a DDOS attack on Amazon EC2?

One of the servers I use is hosted on the Amazon EC2 cloud. Every few months we appear to have a DDOS attack on this sever. This slows the server down incredibly. After around 30 minutes, and ...
18
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2answers
2k views

Is there a Windows equivalent of Unix 'CPU steal time'?

In order to assess performance monitoring accuracy on virtualization platforms, the CPU steal time has become an increasingly relevant metric - see EC2 monitoring: the case of stolen CPU for an ...
18
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3answers
7k views

How can I deploy a scalable, reliable haproxy cluster on Amazon EC2?

We need some more advanced functionality than ELB provides (mostly L7 inspection), but it's not obvious how to handle things like heartbeat and high availability with something like haproxy using EC2. ...
16
votes
2answers
1k views

In AWS, does an hour of usage get charged just for an instance being in the “running” state?

When AWS documentation and pricing refer to "usage" does this simply mean "if the instance is on" instead of "if the instance is on and doing work". E.g., if I had an EC2 instance running but it was ...
16
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2answers
2k views

Which AWS features are EBS backed?

I recently read an article AWS: The good, the bad and ugly, which mentioned that they've moved off of all EBS backed AWS features. What features are explicity (EBS backed EC2 instances) or implicitly ...
15
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4answers
2k views

Why does Amazon release private keys instead of public keys?

My brain is wrapped around the axle on public and private keys. When you create a cloud server (instance) on Amazon's EC2 service and then want to connect to it via SSH, Amazon requires you to ...
15
votes
2answers
4k views

Safe to Use an Amazon EBS Volume While Snapshot in Progress?

Is it safe to use an EBS volumne while a snapshot is being created? I've currently got a 100Gb EBS volume mounted. I am in the process of snapshotting it. Goodness it's slow!! It's going to end up ...
15
votes
1answer
7k views

How do I access the attached volume in Amazon EC2

I just attached another ebs volume to running instance. But how do I access the volume? I can't find the /dev/sda directory anywhere. Where should I look?
15
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6answers
15k views

Tons of TCP connections in TIME_WAIT state on windows 2008 - running on amazon AWS

OS: Windows Server 2008, SP2 (running on EC2 Amazon). Running web app using Apache httpd & tomcat server 6.02 and Web server has keep-alive settings. There are around 69,250 (http port 80) + ...
14
votes
5answers
4k views

Most long-running commands instantly killed on Amazon EC2 (Ubuntu 10.04)

When running any sort of long-running command in the terminal, the program instantly dies and the terminal outputs the text Killed. Any pointers? Maybe there is a log file with data explaining why ...
14
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4answers
3k views

Vagrant box most similar to Amazon EC2 instances

Are there any 'boxes' available to download for Vagrant that closely mirror the Linux version and packages available for Amazon EC2 instances? I am testing locally using Vagrant, currently using the ...
14
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5answers
3k views

Easiest way to automatically check EC2 disk space and be alerted if it is running low?

Running the Amazon Linux AMI. It seems that CloudWatch does not check for free disk space. I have a number of servers and ideally don't want to have to configure each one with a mail server, script to ...
13
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4answers
3k views

What is the “slash” after the IP?

In Amazon EC2, where I set "security groups", It says: Source: 0.0.0.0/0 And then it gives an example of: 192.168.2.0/24 What is "/24"? I know what port and IP is.
13
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4answers
13k views

How to download public key from Amazon AWS?

I have a running amazon ec2 linux instance associated with a keypair (p1) and I have downloaded the private key to my home desktop. Now at work, I created a keypair (p2) on my work desktop and ...
13
votes
3answers
16k views

Where does Amazon publish the range of IP addresses used for EC2 instances by region?

How can I keep updated of changes to the range of IP addresses that Amazon will use for EC2 instances. I want to add a range of IPs to my firewall settings to allow access to my 'ground based' mysql ...
13
votes
3answers
2k views

Some Linux systems become very slow when Redis is loading a big dataset

I received a report from a Redis user, and I'm not sure what to reply as I'm not an expert in the area of Linux and its scheduler, however we (as the Redis project) need to figure this kind of issues ...
12
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1answer
4k views

Delete Amazon EC2 terminated instance

I created an Amazon Free tier Usage Account. I launched two amazon ec2 instances using the online tool. After that one instance was created and running while other was pending which quickly shifted to ...
12
votes
2answers
16k views

Where do I find my EC2 private key?

I'm trying to set up the EC2 API tools and I'm stuck because I cannot figure out where I can obtain the file pointed to by the EC2_PRIVATE_KEY environment variable (I believe I have the EC2_CERT). Of ...
12
votes
4answers
4k views

Running a Small 64bit Amazon EC2?

I'm playing with Amazon EC2, and I've got a 64bit AMI, but when I launch it, the 'Instance Type' only has 'Large', 'Extra Large' and 'High-CPU Extra Large', no 'Small' which the documentation lists as ...
12
votes
1answer
2k views

Can you Transfer an EC2 Instance to another AWS Account

Is there a way to give an entire EC2 instance to a different party. Basically I was managing a EC2 Server for a client and am now giving up maintenance of the server. I don't want to be billed for ...
12
votes
2answers
6k views

How can I run the Ubuntu EC2 AMI images locally?

I've downloaded the Amazon Ubuntu EC2 AMI images (from http://uec-images.ubuntu.com/releases/10.04/release/) and I am trying to run it locally on my linux desktop. Is it possible to run the AMI using ...
12
votes
4answers
3k views

How are Amazon EBS snapshot's sizes calculated?

First, how can I retrieve the space consumed by my EBS snapshots? Second, according to the documentation, Amazon EBS snapshot only backs up the blocks of an EBS volume that have been modified since ...
12
votes
1answer
805 views

Is anyone using an SNMP and/or WMI poller to push custom metrics to Amazon CloudWatch, and if so how?

Amazon CloudWatch has a decent console, and an alarm system which uses Amazon SNS for notifications. Originally it only gave you AWS metrics, e.g. EC2 instance CPU utilization. Recently they added ...
11
votes
4answers
5k views

Speeding up launch of Amazon EC2 Windows instances

I'm working on a Web service which is hosted on EC2 and needs to have a varying number of instances running, depending on load. We have the basic service up and running, but one of the things we're ...
11
votes
3answers
3k views

Amazon EC2 Backup Strategy

I have a couple Web server/DB server setups using Amazon's EC2. I am currently taking daily snapshots of all my system and EBS drives that contains all of my application files, DB files, source code ...
11
votes
3answers
7k views

How do you create a zone apex alias that points to a Elastic Load Balancer in the Route 53 GUI?

I created aliases for my domain name's zone apex using the ELB CLI as described in Elastic Load Balancing Developer Guide. I also added a AAAA record using the --rr-type AAAA flag, which is not ...
11
votes
3answers
4k views

How to recreate a working AMI from recovery snapshot after Aug 8 outage?

After Amazon's Aug 8 outage, all (EBS based) AMIs stopped working for many users. This is due to corruption of some sectors in snapshots that the AMIs are based on. However, Amazon created recovery ...
11
votes
5answers
2k views

How do you keep up with Nagios/Capistrano configs when using EC2?

I use Amazon EC2 for my mobile app. Depending on load of the application at a given time, I might spawn new instances and then take them down when load is lower to save costs. How does one keep up ...
11
votes
2answers
18k views

How to setup SSL on Amazon EC2?

I have just hopped over to Amazon for serving my .net sites and one site requires SSL. I have an elastic IP pointing at my EC2 instance, and I have my site setup in IIS 7 all working fine. I also ...
11
votes
3answers
6k views

What does %st mean in top?

Here is an example from my top: Cpu(s): 6.0%us, 3.0%sy, 0.0%ni, 78.7%id, 0.0%wa, 0.0%hi, 0.3%si, 12.0%st I am trying to figure out the significance of the %st field. I read that it means ...
11
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4answers
2k views

Amazon EC2 spot instances - is there a catch?

I needed to start a new EC2 instance today and decided to try out the new spot instances, where you can reduce your instance cost by bidding on the maximum per-hour price you're prepared to pay. ...
11
votes
5answers
4k views

Amazon EC2: possible to use elastic load balancing across web servers in multiple regions based on location of client?

Related to an another question I asked. This question seems similar but I'm wondering if there are any updates. To support a single site that has users all over the world, I will create EC2 web ...
10
votes
2answers
6k views

EC2 Windows password recover

I can't get the password from the AWS console tools. I can reach the box via rdesktop.Can I reset the password remotely? If so, how to go about doing this? the machine is Windows server 2008 R2 ...
10
votes
2answers
16k views

EC2/Route53: How do I assign my new domain name to an instance?

I have an EC2 instance. It's up and running with an Amazon IP that looks something like this: //ec2-xxx-xxx-xxx-xxx.compute-1.amazonaws.com/ I am sure it works fine. I bought a domain and then set ...
10
votes
3answers
14k views

How to use Amazon Elastic IP?

I get a new elastic IP, I attach it to an instance, but it doesn't work? I can't ping the IP from my local computer either? Am I missing something here? How do I use Amazon Elastic IP? When is a new ...
10
votes
5answers
6k views

Amazon EC2 Ami recommendations for free tier?

Amazon web services recently introduced a free tier, where you basically get free stuff to try out AWS and run tiny sites and projects. Basically it's free as long as you remain below a certain limit ...