The network is working before and I have not change anything on vm. After few months, I can not access the vm instance.
The vm instance is running
I will get "Request timed out" when ping to external network ip address.
I can not access SSH. The SSH port was open properly.
When troubleshooting my connection status of SSH in browser, it is stuck on Network status.
What should I do to know the reason of problem? After I restart the vm instance few times, it will running normally for a period, but the problem will appear again.
Any idea to make sure the vm instance will not disconnect from external network with this reason again?
Here are the resource consuming of my vm
In this case, VESTACP minimum system requirements for VM instances should be okay. But you can also consider the workload process for your VM instance.
I recommend switching to a higher N1 machine types to provide good performance for the workload and machine requirements.
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We have a site to site VPN connection from our AWS cloud to the customer's on site network. Our web application login requires the authentication from the customer's active directory and hence the need for VPN connection.
When our application is not being used for a while the VPN tunnel goes down, due to which when a user tries to log into the application he is unable to due to downed tunnel. It takes some time for the tunnel to get up after which everything works properly.
I had a call with the customer's IT people and it seems they have set up a keep alive bit (DPD settings) on their end but still the tunnel keeps going down. AWS support isn't much of a help either.
I google around and discovered that one way we can keep the tunnel alive is by "sending a ping to the target from the device sourced from the outside interface. A possible destination for the ping is an instance within the VPC"
AWS documentation also suggests "to create a host that sends ICMP requests to an instance in your VPC every 5 seconds."
I already have an private subnet EC2 instance (with only private IP) in my VPC.
My question is, do I need to create another ec2 instance in my VPC private subnet and ping the first one from the other every 5 seconds?
Would I need to write a shell script for this?
I am basically confused about from where to ping, whom to ping and how to ping.
Ping any remote AWS instance from your on-premise site, thereby causing traffic over the vpn. Just schedule it in windows task scheduler, and use the basic command line ping.
I created Ubuntu instance in EC2. And worked fine so far.
But somehow I can't connect to the server by PuTTy anymore and I get Network error: Connection timed out.
The instance is running in the console.
CPU uses just 2%.
InBound Setting seems no problem. SSH with 22 port.
Tried with the IP address and DNS.
restarted the instance and Tried.
Stopped and tried with different IP address.
Instance connection is fine.
This is the screenshot:
This is inbound rule:
How can I solve this problem?
A Connection timeout is a sign that your computer is unable reach the remote computer. Such an error normally takes some time before it fails.
If, instead, the remote computer rejected the connection, the error would appear immediately and the message would be Permission denied.
Things to check:
The Security Group on the EC2 instance needs to allow inbound SSH (port 22) access either from the whole internet (0.0.0.0/0) or, preferably, from a smaller CIDR range that includes your computer (eg choosing "My IP" in the console). This is typically the cause of the issue 80% of the time.
The instance needs to be in a Public Subnet, which means the subnet is connected to an Internet Gateway.
Your network must allow an outbound SSH connection to AWS. Some corporate networks might block this.
There are some other potential causes, but most of the time the cause is one of the above.
I have a load balancer and EC2 instance with AWS. I had problems with e-mail restrictions and was recommended to use an elastic IP. I then read somethere that you can't use elastic IP and a load balancer so I removed the elastic IP. I can no longer access my instance even when I've rebooted it and waiting 2 hours later. I can ping it (after enabling ICMP with network security) but I can't SSH or go to the web server. All the network settings remain, which included allowing TCP ports for HTTP and SSH. Does anyone know what has happened to make port 80 and 23 no longer accessible? This is a real nightmare for me because I did a bit of a marketing campaign, got increased traffic, noticed emails weren't getting sent, then in an attempt to fix that I've screwed the server completely so the website is down at the worst possible time :(
I fixed it all up. This isn't a direct solution to the problem, more like a workaround. I couldn't connect to that server no matter what, so I created a new instance and that worked. It was as if the Linux server itself was corrupt, not the AWS settings. I detached the volume from the old instance and attached it as a secondary volume on the new instance. When I logged into the new instance I was able to mount the secondary volume as a new drive and I just copied the files over that way. I don't have a bloated server so this wasn't really a big deal to pull off. Anyway, if you can't log in to a server anymore, you can always mount it to a new instance and access it via the file-system
My Amazon EC2 small instance stopped responding, I looked at the AWS console and CPU use had gone through the roof. I tried rebooting instance but it didn't respond. So I stopped it and started it again (twice).
Now says the CPU usage is fine (was triggering an alarm when breaching 90%) but still can't login via SSH and Apache is not working (my sites are down).
Anyone give me any idea how I can sort this out? I'm out of my depth a bit as unfamiliar with the ins and outs of EC2.
EDIT: console log http://pastebin.com/JWFeG7NU shows Apache, SSH, etc starting up fine but I can't access via SSH and no response to pinging website hosted on server.
If you have stop/started your instance and you were not using an elastic IP address, your instance IP has changed.
If you were using an elastic IP address, it would have become disassociated.
If you do have applications that are causing you to exceed the allocated CPU, other applications such as ssh, may become slow to respond or not respond at all within the timeout.
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).