EC2 instance connection - amazon-web-services

I have an EC2 instance which until last week I could connect through ssh using a key fine. Since then, I can not connect on it anymore. Also, ping do not respond. But, I can still access my website that runs on that instance. To the best of my knowledge, I havent applied any change on security settings that could be blocking it. Is there any suggestions on what could going on?

Related

New EC2 not connecting to RDS

I lost my PEM and had to create a new EC2. I duplicated it with "make same". I then tried to connect to the RDS database and it gives me cannot connect with user#. now, the IP address of the server has changed, but it is in the same security group, so shouldn't matter.
I changed the user to be from anywhere % and flushed privileges. I even rebooted the DB. I've tried messing with the security stuff, but everything is as it should be, the same as it was before hand when it was working on the previous server.
either something was not "duplicated" when the EC2 was duplicated or there is something somewhere I have to change because the IP of the EC2 changed.
if they are in the same security group, this shouldn't be an issue however.
any help is appreciated. as I can no longer connect to the DB with the app.
the EC2 is linux running a docker container for node.
I can still connect to the RDS via local machine.
So i still don't know what the issue was, but I was able to get around it by creating a new user. I'm thinking that the host wasn't actually changing when I was changing it in RDS - even with a reboot.
If somebody comes across this same issue, try creating a new MySQL user.

Browser returns "No data received" for my Amazon EC2 instance over and over again

I've experienced two times now of the "No data received" issue ever since I've moved my WordPress site to use RDS.
Though I could still connect to my RDS via MySQLWorkbench, but not able to connect to my instance via SSH (It shows "Operation timed out") after this issue has happened each time.
Doing "ping" in Terminal would show that my instance is "100.0% packet loss", and rebooting the instance would not fix this issue neither. I've set the correct IP for the SSH in the security groups inbound rules, and also checked that my instance is appear to be running on the EC2 console. The browser would still returns "No data received.".
Interestingly, I've found that stopping the instance, and then restart the instance and the httpd service would fix the issue. However, this issue will always come back again after couple of hours.
Could anybody help me or guide me to troubleshoot it, please?

Weird ping timeout on AWS EC2 instance

I have an weird issue with EC2 instance:
I start a new Ubuntu instance (or any other).
It initialize the instance and I can ping and connect via SSH, fine...
Suddenly, I can't ping anymore! :(
I have enabled all TCP, UDP and ICMP (inbound and outbound) connections in the instance's Security Group. But no luck.
I also have tried connecting via SSH using Putty. No luck too.
I have searched a lot, but everyone says about the Security Group, which I already had configured to allow all traffic.
Any help will be appreciated! Thanks!
Prints :
http://i.stack.imgur.com/7UtE6.jpg
http://i.stack.imgur.com/E3Ou8.jpg
PS: I don't have reputation to post the images directly... :(
I've just waited and now it seems to be ok.
Maybe it was just a matter of time, wait for AWS to apply the configuration to the EC2 instance (I am using the South America region, São Paulo). But it drove me crazy because I took almost a entire day to try to connect to the instance.

Accessing an Amazon RDS MySQL instance from an IronWorker instance

We're using IronWorkers from http://www.iron.io/ to do some heavy image and PDF processing.
I want to connect an IronWorker instance to a RDS MySQL database on our Amazon AWS account, so that the our code running on the IronWorker can directly make chances in this database.
I'm not too sure how to go about this, as we have a few technical issues to work around.
My understanding is that IronWorkers that get launched won't be in the RDS instance's security group, and would be blocked from accessing our RDS MySQL instance. It won't be possible to create a security group, by creating an CIDR/IP entry either, since we don't know what the IP address for the launched server is going to be.
Another approach would be to somehow get the .pem file on the launched instance, and configure the MySQL connection to use a PEM file through SSH, but I'm not too convinced that it's the most secure way to go about achieving a connection.
Does anyone know of any means a direct connection can be made from an IronWorker instance to a MySQL RDS instance?
There's a tricky way to get around this by finding the internal IP of your RDS instance then using that instead of the dns entry AWS gives you, example:
$ ping myserverabcdefg.us-east-1.rds.amazonaws.com
PING ec2-X-XX-XXX-X.compute-1.amazonaws.com (10.111.222.33) 56(84) bytes of data.
Then add a dns entry using that internal host and and use the new dns entry in your workers.
Let us know how that works.

I can ping my EC2 instance, but I cannot connect through ssh

A while back I had created an RHEL EC2 instance. Set it up correctly and was able to connect to it through putty and WINSCP. Over time it hasn't been used but until recently it needed to be accessed again. I went to check to login but wasn't able to. So i reboot the instance and try to reconnect but I cannot anymore. I get the error "Network error: Connection refused."
I tried recreating the ppk from pem, and also enable all ports to all IP's. What could have caused this un-reachability and are there any troubleshooting tips for me to connect to it again?
There are a few things to check here:
Did you have anything running on the box that might have caused it to become unresponsive over time? This is somewhat unlikely since you said you rebooted the machine.
Check your security group settings to ensure that the firewall is not blocking your SSH port. The instance has no way of knowing whether connections will actually be accepted by the Amazon network on the SSH listening port.
Amazon hardware can fail and cause your instance to become unresponsive. Go to the Instances page on your EC2 console and see if 2/2 of the status checks are passing. If less than 2 are passing, this is probably a failed instance situation.
As a last resort, try right-clicking the instance and checking the system log for anything that might have caused the instance to not listen for SSH connections.
Hopefully you have your data on an EBS volume such that you can simply stop and start the instance and have it come up on different hardware. While it would be nice if Amazon provided console level access to the box, unfortunately they do not presently (as far as I know).