Hello,
Thank you for the post.
I took a look at your instance with IP address: 50.18.176.3 and found that it is operating normally at the infrastructure level. I also tried to connect on port 22 (SSH) and I was able to connect using a 'netcat' command. Please find the output of my command below:
nc -v 50.18.176.3 22
Connection to 50.18.176.3 22 port tcp/ssh succeeded!
From the above output, it seems that the instance is allowing connections on port 22 (SSH).
In general, please refer to this documentation for more information about 'Troubleshooting Connecting to Your Instance': http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/TroubleshootingInstancesConnecting.html
Also, I tried to perform ping and I was unable to ping the instance on IP: 50.18.176.3. Looking at the instance's security group: default, I found that you have specified the same security group: default, as a source to allow ICMP traffic. This rule allows instances associated with this specified security group (default) to ping instances associated with this security group.
In general, when you specify a security group as the source or destination for a rule, the rule affects all instances associated with the security group. Incoming traffic is allowed based on the private IP addresses of the instances that are associated with the source security group.
You can find more information about 'Security Group Rules' on this documentation: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-network-security.html#security-group-rules
I hope the above information helps.
Thank you,
Nikhil

Thank you for your response!
The ICMP rule I had just added recently because I read that would help. I couldn't ping the instance before I added the rule. I removed it and still can't ping it.
I'm unable to SSH or FTP into my instance unless I reboot the instance, and after somewhere around 4 hours after rebooting I can no longer SSH or FTP.
The SSH error I get is either:
Read from socket failed: Connection reset by peer
OR
ssh_exchange_identification: read: Connection reset by peer
And my FTP says that it's not accessible.
I simply can't get an answer on this. AWS said to upgrade my instance size. This can't be it as I have low traffic.
Is the instance corrupted?
It it getting spammed?

Hello,
Generally 'Instance Status Check' verifies that your instance's operating system is accepting traffic.
When it fails it means that the operating system inside the instance is not responding to traffic, for example this can happen when a Windows instance hangs or when a Linux instance kernel panics or network is disabled inside the instance.
I had a look at your account and there is one instance in there, looking at the instance it seems that you have rebooted the instance and I could make successful connection to port 22 and 80 on the instance as those ports are open to world.
I also had a look at the underlying host of the instance and could not see any issues on the underlying host. I would recommend you to check system and kernel logs before the reboot to track down what has happened.
'502 Bad Gateway' could also be a sign of the webserver not responding in timely manner, which is in line with the fact that CloudWatch has recorded constant 100% CPU usage for your instance.
Given the fact that your instance is a t.micro instance, if the high load is legitimate you may want to consider migrating to a larger instance type like m1.small for example.
Kind regards,
Mostafa S.

Thank for your advice.
Let me try to migrate it to other larger instance.
If it still get a problem i will reach you again.
Regards,

Hi Mostafa S,
I would like to inform you one more thing that sometime my website appear an error message '504 Gateway Time-out'.
What is this message about?
Regards,
Han
Edited by: hychanhan on Jan 5, 2014 7:32 AM

Hello,
Thank you for the update. I would like to investigate your ec2 server, however, I might need more information from you. Can you please provide me with your ec2 instance ID?
Regards,
Marcin

Hi Marcin,
I have solved the problem already.
The problem caused from my server was running out of storage.
And now I just created another snapshot for a new volume 25GB more.
It is working fine now.
Thank you so much.

Best Regards,
ChanHan

EC2 instance stuck in 'stopping' state, pls resolve it
Hi EC2 support,
My EC2 instance, stops all the time, so I have to manually reboot it through the AWS EC2 Management Console. That's a huge problem, because, as a result my webpage stops working, pretty much plenty times per day too, along with my EC2 instance, because if I try to ssh, I'll always get 'ssh_exchange_identification: read: Connection reset by peer', while my instance is in that state . Please, get it resolved.
My instance id is: i-06b8743cb2461b1dd
Thanks,
Mil

Hi,
My site giving 502 bad gateway.pls help.instance id is. i-04dc8c91a36f3b1a7
Now i stated getting database error.
We didnot change any credentials.
Please check if database is up and running.