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

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136
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13answers
360k views

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 ...
77
votes
4answers
14k 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 ...
76
votes
5answers
47k 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?
64
votes
2answers
17k 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 ...
48
votes
4answers
58k 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 ...
45
votes
4answers
19k 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?
39
votes
6answers
25k 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?
33
votes
4answers
16k 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 ...
31
votes
3answers
23k 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
votes
3answers
12k views

How can I check /dev/xvda1?

On login to EC2 (Ubuntu) instance, I see *** /dev/xvda1 should be checked for errors *** I can't fsck /dev/xvda1 because it is mounted, and sudo umount /dev/xvda1 fails because it is in use. lsof ...
29
votes
6answers
34k 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 ...
29
votes
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 ...
28
votes
1answer
13k views

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

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 successfully go to this server ...
27
votes
1answer
9k 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 ...
27
votes
7answers
26k views

Amazon Linux vs. Ubuntu for Amazon EC2 [closed]

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 ...
26
votes
1answer
13k 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?
24
votes
3answers
23k 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 ...
24
votes
4answers
7k 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 ...
23
votes
4answers
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
3answers
9k 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. ...
21
votes
1answer
4k 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 ...
20
votes
2answers
7k 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 ...
19
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 ...
19
votes
2answers
24k views

Bandwidth limits for Amazon EC2

I have a micro instance on Amazon EC2 cloud. Also the instance is small and it has vary low CPU and EAM usage but it generates a lot of content, so it can be considered like a web server serving ...
18
votes
1answer
13k views

AWS, Bandwidth and content delivery

My question is about Virtual Machines and delivering their content over the servers connection to the internet. I have an Ec2 windows instance, and its network connection appears to be 100mbps If I ...
18
votes
2answers
3k views

Why does my OpenSSH key fingerprint not match the AWS EC2 console keypair fingerprint?

When I import my OpenSSH public key into AWS EC2's keyring the fingerprint that AWS shows doesn't match what I see from: ssh-keygen -l -f my_key It is a different length and has different bytes. ...
18
votes
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
votes
5answers
5k 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 ...
17
votes
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 ...
17
votes
4answers
14k views

Why can't I connect to Amazon RDS after setting it up?

So, I just created the Amazon RDS account. And I started an instance of database. The "endpoint" is: abcw3n-prod.cbmbuiv8aakk.us-east-1.rds.amazonaws.com Great! Now I try to connect to it from one ...
16
votes
4answers
20k views

How to copy files to Amazon EC2 Windows instance from my local machine?

I have created a new Windows instance on Amazon EC2. I want to copy some files from my local machine to the instance. How do I go about it?
16
votes
6answers
27k 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) + ...
16
votes
4answers
10k views

Create an AWS HVM Linux AMI from an Existing Paravirtual Linux AMI

Is it possible to create a hardware virtual machine (HVM) AMI from an existing paravirtual (PV) AMI. My initially thought was to start a new PV instance and use the ec2-create-image command to ...
16
votes
1answer
761 views

can't type lower cased e in amazon ec2 (Amazon Linux)

After a few days of operation on my new ec2 build, the following happens: I log into SSH, everything is fine, I do my coding I return the next day, and log into SSH I cannot type a lower cased e ...
16
votes
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
votes
3answers
5k views

EC2 drive not EBS volume size

I have an EC2 instance which I created a 500GB EBS volume for. Unfortunately, the EC2 instance shows only 8GB available. I have only one drive, which is right. [root@ip-10-244-134-250 ~]# ls -la ...
15
votes
6answers
3k views

How to know if a machine is an EC2 instance

I would like to run some scripts on hosts which are EC2 instances but I don't know how to be sure that the host is really an EC2 instance. I have made some tests, but this is not sufficient: Test ...
14
votes
4answers
17k 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 ...
14
votes
5answers
5k 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
votes
4answers
6k 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.
14
votes
2answers
18k 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 ...
14
votes
3answers
6k views

How to change the name and description of an AWS EC2 security group?

How do you change the name and description of a security group in AWS EC2? My security group is named quick-start-1 (the default) and I want to change it to "HTTP, HTTPS and Limited SSH".
14
votes
1answer
7k views

What is “freeable memory”?

Amazon RDS has a metric for 'freeable memory'. It appears to go up & down in a sawtooth pattern. This leads me to believe that it's memory that is being used by MySQL for caching and that when ...
14
votes
1answer
56k views

How to add user with SFTP/ FTP access to '/var/www/html/website_abc' folder on Amazon EC2 Centos?

Possible Duplicate: Linux directory permissions I'm working with some third-party developers and I would like to grant SFTP (or FTP) access to the root folder for a website they're working ...
14
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 ...
13
votes
5answers
6k views

How can I make my web server reachable via IPv6 on the AWS platform?

My business's web site uses the AWS platform. I want the site's visitors to be able to reach my content using the IPv6 protocol. How can I add an IPv6 address?
13
votes
3answers
5k views

updates in amazon-ec2 ubuntu 10.04 server

I keep getting this message when I logged into my server in ec2 via ssh think this is called MOTD 43 packages can be updated. 22 updates are security updates. but I have already done sudo ...
13
votes
2answers
23k 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 ...
13
votes
2answers
6k views

Are EC2 security group changes effective immediately for running instances?

I have an EC2 instance running, and it belongs to a security group. If I add a new allowed connection to that security group through AWS Management Console, should that change be effective ...
13
votes
2answers
5k views

How to resize Amazon EC2 instance?

Is it possible to resize an Amazon EC2 instance, e.g. convert from a small instance to a large instance? If so, what is the easiest way to resize Amazon EC2 instance? Like Rackspace Cloud Servers do ...