About 6 months ago I created an AWS EC2 instance to mess around with on the free tier. After months of having no issues remoting into my AWS EC2 server, I've recently been unable to access it via SSH. I am using the following command:
ssh -i my-key-pair.pem ec2-user#ec2-**-**-***-***.us-****-*.compute.amazonaws.com
...and after a minute or two, am getting this response
ssh: connect to host ec2-**-**-***-***.us-****-*.compute.amazonaws.com port 22: Operation timed out
What's strange is that
1) I can read and write to my RDS database just fine
2) I can ping into the server
3) My port 22 is open
4) The instance is running and healthy
5) In the Inbound section of the security group of the EC2 server it allows for all traffic and SSH from any location via port 22.
6) I'm using the same key-pair as always
I went through this documentation (https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/TroubleshootingInstancesConnecting.html) and can confirm that the VPC, subnet, network ACL and route tables all line up (I haven't changed anything with those since the SSH stopped working). Any insight would be extremely helpful!
Sometimes the instance fails, you can check the screen of it via AWS
console.
Run another instance in the same security group and try to
connect to it and then from there to your original one - to verify if
ssh is still open (even if you do not have the ssh key, the error
will not be 'timeout')
You can create a snapshot of your instance and
attach it as another volume in a new one and you can investigate
logs, maybe something went wrong.
You can restart the instance, if
for example i ran out of memory it will most likely work after the
reboot (hopefully for a long enough time for you to investigate).
You can contact AWS support.
Related
Launching an AWS EC2 instance seems quite straightforward although when it comes to connecting to the newly launched instance things get sticky. The process for connecting to an instance proposed by such a tech giant is very counter-intuitive.
As a short reminder I should add that an "instance" is technically a virtual machine running on Amazon's Elastic Compute Cloud (EC2), for more info one could have a look at this link.
The ec2 instance referred to in this discussion is Ubuntu Server 20.04 LTS (HVM).
The instruction for working with EC2 Linux instances is given here.
AWS EC2 proposes three different ways of connecting to an instance:
EC2 Instance connect (browser-based SSH connection),
Session Manager
SSH Client
Now with regard to connecting to the above-mentioned instance there are only certain connections that establish correctly and the rest of the proposed methods fail, here is the list of connection successes and failures :
Ubuntu instance, security group source "Custom=0.0.0.0/0", Connection establishes using both EC2 Instance Connect (browser-based SSH connection) and SSH client.
Ubuntu instance, security group source "My IP=$IP", Connection establishes only using SSH client (terminal on Ubuntu and PuTTY on windows) and not using EC2 instance connect.
Both above cases have been tried on Ubuntu 20.04 and Windows 10 as local machine and the problem remains similar on both machines. I went through most of the failure cases discussed in the troubleshooting documents proposed here and verified them on my instance. Yet the problem persists. I should also add that I never tried "session manager" connection method although opening its tab already would give some info about "not installed" agents and features.
Any idea regarding this problem? Somebody out there facing the same issue?
From Docs
(Amazon EC2 console browser-based client) We recommend that your instance allows inbound SSH traffic from the recommended IP block published for the service.
Reason for this -> EC2 Instance Connect works by making an HTTPS connection between your web browser and the backend EC2 Instance Connect service on aws. Then, EC2 Instance Connect establishes a "mostly normal" SSH connection to the target instance in other words the request is going from backend ec2 instance connect and not your browser that is why it needs IP address from accepted ranges of that region .
Browser based EC2 Instance Connect uses specific IP ranges for browser-based SSH connections to your instance. These IP ranges differ between AWS Regions. To find the AWS IP address range for EC2 Instance Connect in a specific Region, use the following( just replace your region with your region) ( for Linux required curl and jq as prerequisite)
curl -s https://ip-ranges.amazonaws.com/ip-ranges.json| jq -r '.prefixes[] | select(.region=="Your region") | select(.service=="EC2_INSTANCE_CONNECT") | .ip_prefix'
whatever the value is returned just add up to your security rule and it will work.
Ubuntu instance, security group source "Custom=0.0.0.0/0", Connection establishes using both EC2 Instance Connect (browser-based SSH connection) and SSH client.
this works because 0.0.0.0/0 allows connection from all the IP ranges( which includes your region IP too).
for more details try reading this troubleshoot
I tried to connect to a running ec2 instance with my usual settings, it returns
ssh: connect to host ec2 port 22: Connection timed out
I tried to connect with the built-in "EC2 Instance Connect", to connect directly from the browser with the AWS account, it returns
There was a problem setting up the instance connection An error
occurred and we were unable to connect or stay connected to your
instance. If this instance has just started up, try again in a minute
or two.
The instance was running for weeks, I am the only user with access to the AWS account and the SSH Keys and I didn t change any setting in the last ~3 weeks or restarted it
1st the timeout started ~1 week ago, nand then without any other change, my website (wordpress) suddenly started to show a database connection error (the database in inside the EC2 instance as well)
What I used to connect :
Either
ssh -i "Keys.pem" ec2-user#ec2-[public ip].eu-west-3.compute.amazonaws.com
Or
ssh ec2-user#[public ip] -i "Keys.pem"
Both show the same error. I used the first one several weeks ago and it used to work well
This timeout will be caused by invalid security group rules.
Ensure that the security group rules attached to your instance allow inbound access from the source IP address you're trying to SSH from, the database connection may also be related to this.
If you're connecting using a dynamic public IP address to SSH to your host, you will need to adjust this every time your IP address changes. It might be more appropriate to setup a VPN so that you can connect privately to your host.
I am new to setting up virtual machines. I created my first Ubuntu instance using AWS EC2. Everything seemed to check out until I tried connecting to it with ssh, as per instructions.
To provide some context, my app is called "smpapp". My computer is macOS High Sierra. Naturally, my smpapp.pem file saved to ~/Downloads. First, I opened up the Terminal and set my working directory to Downloads with cd ~/Downloads. Then I entered chmod 400 smpapp.pem, which didn't return any error, so I assume it was a success. Then, I entered ssh -i "smpapp.pem" ubuntu#ec2-XX-XX-XXX-XXX.us-east-2.compute.amazonaws.com (omitting public DNS numbers with Xs). It took awhile to process before spitting out, ssh: connect to host ec2-XX-XX-XXX-XXX.us-east-2.compute.amazonaws.com port 22: Operation timed out.
Can someone explain the general problem to me and how I can fix it (methodically and in layman's terms)?
Could be a few things:
Does your ec2 instance have a public ip? (if not, you might have to attach an elastic ip or put it in a public subnet)
Is the security group attached to the ec2 instance allowing connections to port 22?
Is the ACL on the subnet allowing public connections to the subnet?
Is your VPC configured to routetraffic through your IGW?
Amazon offers step by step instructions on determining the issue, it could be for any reason of the above not being configured properly. You can find step by step instructions on what do in the official amazon docs here.
Yesterday, I updated my Django website (on AWS EC2) to HTTPS by using lets-encrypt. Everything works well. The website has HTTPS green icon as expected.
Today when I try to connect my instance by using SSH. The connection keep hunging. Finally, It give some message like "ssh: connect to host ec2-34-202-93-189.compute-1.amazonaws.com port 22: Resource temporarily unavailable".
I thought it might be security group problem of this instance. So I double checked my security group setting of this instance, the SSH, HTTP and HTTPS port are all open correctly. I created another instance to test if there is any problem on my local. The new instance connected successfully. Then I apply the new instance to the security group that I made for the previous instance and It connected. Then I apply the previous instance to the new security that I made for the new instance, the connection got frozen again. I also tried to connect with putty and it was not working as well.
Now I am really confused. My local machine is Windows subsystem of Linux. My EC2 instance is Ubuntu 16. I am using Nginx as web server. My ssh command is "ssh -i blog_project.pem ubuntu#ec2-34-202-93-189.compute-1.amazonaws.com".
Here is my security group setup for the instance.
This is the result I command "ssh -vvv -i blog_project.pem ubuntu#ec2-34-202-93-189.compute-1.amazonaws.com"
BTW, Is there any way that I can login to my instance without ssh connection? Is there anything like console or shell inside the AWS that I can touch with my instance?
Check if the instance exists on AWS, maybe a new one was created with different Public DNS (xxxx.compute-1.amazonaws.com) than the one you are using in your command.
I am currently overseas and I am trying to connect to my EC2 instance through ssh but I am getting the error ssh: connect to host ec2-34-207-64-42.compute-1.amazonaws.com port 22: Connection refused
I turned on my vpn to New York but still nothing changes. What reasons could there be for not being able to connect to this instance?
The instance is still running and serving the website but I am not able to connect through ssh. Is this a problem with the wifi where I am staying or with the instance itself?
My debugging steps to EC2 connection time out
Double check the security group access for port 22
Make sure you have your current IP on there and update to be sure it hasn't changed
Make sure the key pair you're attempting to use corresponds to the one attached to your EC2
Make sure your key pair on your local machine is chmod'ed correctly. I believe it's chmod 600 keypair.pem check this
Make sure you're in either your .ssh folder on your host OR correctly referencing it: HOME/.ssh/key.pem
Last weird totally wishy washy checks:
reboot instance
assign elastic IP and access that
switch from using the IP to Public DNS
add a : at the end of user#ip:
Totally mystical debugging sets for 6 though. That's part of the "my code doesn't work - don't know why. My code does work - don't know why." Category
Note:
If you access your EC2 while you are connected to a VPN, do know that your IP changes! So enable incoming traffic from your VPN's IP on your EC2 security group.
In AWS, navigate to Services > EC2.
Under Resources, select Running Instances.
Highlight your instance and click Connect.
In Terminal, cd into the directory containing your key and copy the command in step 3 under "To access your instance."
In Terminal, run: ssh -vvv -i [MyEC2Key].pem ec2-user#xx.xx.xx.xx(xx.xx.xx.xx = your EC2 Public IP) OR run the command in the example under step 4.
Just check if your public ip that you get when you are on VPN is configured as a source address in the SG inbound entry that opens up port 22.
You can check your ip using https://www.google.co.in/search?q=whats+my+ip, when connected to your VPN.
I tried everything in this and several other answers, also in some aws youtube videos. Lost perhaps five hours over a few sessions trying to solve it and now finally..
I was getting the exact same error message as the OP. I even rented another EC2 instance in a nearer data centre for twenty minutes to see if that was it.
Then I thought it might be the router or internet provider in the guest house where I am staying. Had already noticed that some non-mainstream news sites had been blocked - and that was it!
You can check if the router is blocking port 22:
https://superuser.com/questions/1336054/how-to-detect-if-a-network-is-blocking-outgoing-ports
cardamom#neptune $ time nmap -p 22 portquiz.net
Starting Nmap 7.70 ( https://nmap.org ) at 2021-02-03 20:43 CET
Nmap scan report for portquiz.net (27.39.379.385)
Host is up (0.028s latency).
rDNS record for 27.39.379.385: ec2-27-39-379-385.eu-west-3.compute.amazonaws.com
PORT STATE SERVICE
22/tcp closed ssh
Nmap done: 1 IP address (1 host up) scanned in 0.19 seconds
real 0m0,212s
user 0m0,034s
sys 0m0,017s
Then, the question of why someone would want to block the ssh port 22 is addressed in at length here:
https://serverfault.com/questions/25545/why-block-port-22-outbound
Had the same problem after creating some instances on a new VPC. (If internet SSH worked before this solution may not work for you)
When creating a new VPC, make sure you create an internet gateway (VPC -> Internet Gateways)
And also make sure that your VPC's routing table (VPC -> Route Tables) has an entry which redirects all IPs (or just your IP) to the internet gateway you just created.
For me, it was because of this:
NOT ec2-user#xx.xx.xx.xx
BUT THIS =>>> ubuntu#xx.xx.xx.xx
Watch the image of EC2 instance!
Instead of
ssh -i "key.pem" ubuntu#ec2-161-smth.com
use
ssh -i "key.pem" ec2-user#ec2-161-smth.com