Questions tagged [amazon-ec2]
Amazon Elastic Compute Cloud (EC2) provides self-service, on-demand, pay-for-what-you-use computing infrastructure resources.
6,604
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Permission denied (publickey). SSH from local Ubuntu to Amazon EC2 server
I have an instance of an application running in the cloud on an Amazon EC2 instance, and I need to connect to it from my local Ubuntu. It works fine on one local ubuntu and also laptop. I got this ...
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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 ...
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How can I upgrade to Java 1.8 on an Amazon Linux Server?
I tried sudo yum update but it just keeps java "1.7.0_75". I need 1.8 for it to work with another application but can't figure out how to upgrade it.
Do I need to manually install it somehow? There's ...
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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 ...
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What Linux distribution is the Amazon Linux AMI based on?
Amazon Web Services (AWS) offers an officially supported Amazon Machine Image (AMI), but it doesn't indicate which Linux distribution it's based upon.
Is the official Amazon Linux AMI based on ...
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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?
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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.
...
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103
votes
9
answers
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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?
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How to get a .pem file from ssh key pair?
I created a key pair using ssh-keygen and get the two clasic id_rsa and id_rsa.pub.
I imported the public key into my AWS EC2 account.
Now I created a windows instance and to decrypt that instance ...
user120858
96
votes
6
answers
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Assign Public IP (not Elastic IP) after instance launched
When I launch instance in AWS console I can set "Auto-assign Public IP" to true and newly created instance will be assigned with public IP address from pool.
Now assume I have launched instance with ...
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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?
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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".
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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 ...
- 1,061
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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 ...
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What is the difference between PV and HVM virtualization types in ec2?
AWS EC2 offers two types of virtualization of Ubuntu Linux EC2 machines - PV and HVM.
PV:
HVM:
What is the difference between these types?
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Cannot SSH: debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY [closed]
We have a server on Amazon EC2 running SSH is on a standard (22) port.
I placed my public key at the <username>/.ssh/authorized_keys file.
The fun thing is that yesterday it was working great! ...
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votes
10
answers
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xvda1 is 100% full, What is it? how to fix?
I'm running a Linux instance on EC2 (I have MongoDB and node.js installed) and I'm getting this error:
Cannot write: No space left on device
I think I've tracked it down to this file, here is the df ...
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votes
3
answers
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Search ec2 instance by its name from aws command line tool
I have an instance named dev-server-03. Now how can I search all dev-server-* instances from command line?
I am using aws cli tool.
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What is the "slash" after the IP? [duplicate]
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.
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4
answers
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Download SSL certificate from aws certificate manager
I am using aws certificate manager for managing SSL. Recently I purchased a wildcard ssl *.example-private.com Now I need that SSL certificate to deploy on enterprise git instance on aws.
How can i ...
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votes
5
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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 ...
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14
answers
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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 ...
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votes
4
answers
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Multiple EC2 security groups - permissive or restrictive?
What happens when I assign multiple security groups to an instance? Is it permissive in the sense that the traffic is allowed in if any one of the security groups allows it. OR is it restrictive in ...
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How to determine AWS security group dependencies?
Amazon EC2 won't let me delete a security group, complaining that the group still has dependencies. How Can I find what those dependencies are?
aws ec2 describe-security-groups doesn't say.
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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 ...
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answers
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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 immediately?...
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votes
7
answers
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How to delete EC2 AMI
I know that the command ec2-create-image instance-id will be creating an image of the ec2 instance, creating snapshots file and registering as an AMI. But what is the equivalent command to delete the ...
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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 ...
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How to install Docker on AWS EC2 instance with AMI (CE/EE Update)
What is the current way of installing Docker on an AWS EC2 instance running the AMI?
There has been an announcement of Docker Enterprise Edition and now I want to know if anything has changed.
Until ...
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Can't connect to EC2 instance in VPC (Amazon AWS)
I've taken the following steps:
Created a VPC (with a single public subnet)
Added an EC2 instance to the VPC
Allocated an elastic IP
Associated the elastic IP with the instance
Created a security ...
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votes
7
answers
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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 ...
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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 ...
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Why can't I reach my Amazon EC2 instance via its Elastic IP address?
The server works fine via the Amazon assigned DNS entry, but I cannot reach it (using a browser) via the Elastic IP address Amazon assigned the box. Ping does not work either. I am trying to confirm ...
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votes
2
answers
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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 ...
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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 -- ...
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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 ...
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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 ...
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5
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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 ...
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votes
1
answer
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"500 Illegal PORT command" using command-line ftp [closed]
Has anyone figured out how to ftp a file down to a EC2 AMI using ubuntu on the command line?
I am able to connect to ftp.drupal.org (I'm trying to dowmload a Drupal module) and then I can't even ...
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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 ...
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2
answers
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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?
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"A new version of /boot/grub/menu.lst is available" when upgrading Ubuntu on an AWS server
I just tried to do a sudo do_release_upgrade on an AWS EC2 Ubuntu 13.10 server to upgrade to 14.04. All was going well until I got the following message:
A new version of /boot/grub/menu.lst is ...
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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 ...
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2
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Fundamental difference between t3 and t3a EC2 instances
Both T3 and T3a instances offer the same configuration, CPU credits and network performance. The only difference that I find is T3 uses Intel processor while T3a uses AMD processor, while both are ...
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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 the ...
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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 ...
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4
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How to make EC2 user data script run again on startup?
After cloud-init runs a user data script on the first boot of an EC2 instance, a state file is presumably written so that cloud-init won't run the script again on subsequent reboots. There are cases ...
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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 steal ...
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votes
3
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Cannot mount an existing EBS on AWS
I tried mounting an existing EBS Storage (which has data) to an instance, but it keeps throwing this error.
mount: wrong fs type, bad option, bad superblock on /dev/xvdf,
missing codepage or ...
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8
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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?
Mayuresh