I need to reduce my Windows EBS root volume.
We are able to increase the root volume by using AWS Console. So I have followed some document to decrease my Windows EBS root volume:
I created a new 30GB volume and attached it to my existing instance
I then used xcopy to copy the data from C:\ to D:\ which is newly attached volume
After completion of copying data, I then stopped the instance and detached both the EBS root volume and the newly added volume.
Then I reattached the newly created volume to the stopped EC2 instance as /dev/sda1
Now I am trying to start my Windows EC2 instance, but it fails to start. It is coming again and again to stopped state.
Note: I received error message like Sharing Violation after data copied.
Related
Scenario
I currently have an EC2 instance with a root EBS volume attached to it of 30gb and i have some files stored in that EBS
If i delete the EC2 instance and have delete on termination false then EBS persists.
Desired outcome
I want to provision a new EC2 (provisioned by auto scaling group) instance such that it uses the old EBS volume as its root volume which was detached as a result of me terminating the old instance
Note
I want to have the liberty of choosing OS of newly provisioned EC2 so creating an AMI does not work
You cannot directly launch a new Amazon EC2 instance with an existing Amazon EBS volume. Instead, you would need to:
Launch a new Amazon EC2 instance with a new root volume
Stop the instance
Detach the root volume
Attach the 'old' EBS volume
Start the instance
Storing data in root EBS volume might be a bad idea to start with.
Consider one of the following:
Mount another EBS volume to the instance to store required data only.
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-using-volumes.html
best performance, highest cost/effort, but your application doesn't
change a bit.
Create EFS and mount it to your instances. https://docs.aws.amazon.com/efs/latest/ug/mounting-fs.html -
reasonable effort, minimal if any changes to the application.
Store data in S3. Ideal from price standpoint; requires changes to the application.
Can someone help me to understand the difference between Root device and Block devices for EC2 instance. You can see a snapshot i posted below.
What i tried to achieve is :
I created a snapshot of the attached volume of the EC2.
Detached the volume from instance.
Deleted the volume.
Created a new volume from the snapshot.
Reattached the newly created volume to the instance.
But it only attaches to the Block Devices but not to the root devices. And results in the failure to launch the instance.
My apologies if my question is wrong.
Awaiting your reply.
Thanks in advance.
The Root device is the EBS volume for the AMI in which your instance is based on. This will contain the operating system. If not configured then, AWS will use the default values of the AMI.
You can configure additional Block device entries optionally to mount additional volumes on the instance, besides the root volume. It can be empty or from a snapshot.
One of my instances was preventing me from logging so I stopped it, detached its volume, spun up a new instance, and attached the old volume. The problem is, the old volume is being treated as the root device. Because of this, I still cannot log in to the new instance (although I can do so if I don't attach the old volume).
Is there any way to fix this issue using the AWS Management Console?
It seems like you have attached your old volume in "/dev/sda1". Deattach your old volume and attach it to "/dev/sdf".
This is caused by the filesystems on each volume having the same label (the value returned by e.g. e2label /dev/xvda1). The server correctly starts booting from the first volume, and then the bootloader, there, sees the second volume having the label it anticipates for the root volume, and continues booting with the second volume as root. This an os-level setting, not visible to the AWS infrastructure.
Workaround: don't attach the second volume until after the instance has booted. EBS volumes can be attached to an instance at any time -- they don't have to be present when the instance is started. After unmount, they can also be detached at any time, with the instance still running.
To resolve this, I had to make a snapshot of the old volume first. I then created a new AMI using that snapshot. I included the old volume as an extra storage so that it's explicitly defined not to be treated as a root device.
I then created a new instance using that AMI. I was able to finally log in to the new instance. From there, I just mounted the volume.
I created snapshot, from volume(Root volume).
After one day, I need to set my snapshot as root volume.
I followed these steps :
For that I created a volume from snapshot.
My working instance was stopped.
Detached root volume of my instance
Attached the volume generated from snapshot as /dev/sda1
and then instance started
I have a problem while starting my instance, it was not starting and no errors occurred.
Can you guys please check the process and let me know if anything else required
I am trying to stop a Amazon EC2 instance and get the warning message
Warning: Please note that any data on the ephemeral storage of your instance will be lost when it is stopped.
My Question
What data is stored in ephemeral storage of an Amazon EC2 instance?
Basically, root volume (your entire virtual system disk) is ephemeral, but only if you choose to create AMI backed by Amazon EC2 instance store.
If you choose to create AMI backed by EBS then your root volume is backed by EBS and everything you have on your root volume will be saved between reboots.
If you are not sure what type of volume you have, look under EC2->Elastic Block Store->Volumes in your AWS console and if your AMI root volume is listed there then you are safe. Also, if you go to EC2->Instances and then look under column "Root device type" of your instance and if it says "ebs", then you don't have to worry about data on your root device.
More details here: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/RootDeviceStorage.html
Anything that is not stored on an EBS volume that is mounted to the instance will be lost.
For example, if you mount your EBS volume at /mystuff, then anything not in /mystuff will be lost. If you don't mount an ebs volume and save stuff on it, then I believe everything will be lost.
You can create an AMI from your current machine state, which will contain everything in your ephemeral storage. Then, when you launch a new instance based on that AMI it will contain everything as it is now.
Update: to clarify based on comments by mattgmg1990 and glenn bech:
Note that there is a difference between "stop" and "terminate". If you "stop" an instance that is backed by EBS then the information on the root volume will still be in the same state when you "start" the machine again. According to the documentation, "By default, the root device volume and the other Amazon EBS volumes attached when you launch an Amazon EBS-backed instance are automatically deleted when the instance terminates" but you can modify that via configuration.
To be clear and answer #Dean's question: EBS-type root storage doesn't seem to be ephemeral. Data is persistent across reboots and actually it doesn't make any sense to use ebs-backed root volume which is 'ephemeral'. This wouldn't be different from image-based root volume.
For EC2 instance
Stop & Start != Reboot
so for ephemeral storage (Instance Store)
Stop cause data lost
Reboot will not
According to AWS documentation [https://aws.amazon.com/premiumsupport/knowledge-center/instance-store-vs-ebs/] instance store volumes is not persistent through instance stops, terminations, or hardware failures.
Any AMI created from instance stored disk doesn't contain data present in instance store so all instances launched by this AMI will not have data stored in instance store. Instance store can be used as cache for applications running on instance, for all persistent data you should use EBS.
ephemeral is just another name of root volume when you launch Instance from AMI backed from Amazon EC2 instance store
So Everything will be stored on ephemeral.
if you have launched your instance from AMI backed by EBS volume then your instance does not have ephemeral.
refer: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/InstanceStorage.html#instance-store-volumes
The data in an instance store persists only during the lifetime of
its associated instance. If an instance reboots (intentionally or
unintentionally), data in the instance store persists. However,
data in the instance store is lost under any of the following
circumstances:
- The underlying disk drive fails
- The instance stops
- The instance hibernates
- The instance terminates