Install and update requirements

Install or update the AWS CLI

sudo yum remove awscli

To update your current installation of AWS CLI, download a new installer each time you update to overwrite previous versions. Follow these steps from the command line to install the AWS CLI on Linux.

$ curl "https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip" -o "awscliv2.zip"
unzip awscliv2.zip
sudo ./aws/install

Instance store swap volumes

Swap space in Linux can be used when a system requires more memory than it has been physically allocated. When swap space is enabled, Linux systems can swap infrequently used memory pages from physical memory to swap space (either a dedicated partition or a swap file in an existing file system) and free up that space for memory pages that require high-speed access.

[ec2-user ~]$ swapon -s
Filename                                Type            Size    Used    Priority
/dev/xvda3                              partition       917500  0       -1

The above instance has a 900 MiB swap volume attached and enabled. If you don't see a swap volume listed with this command, you may need to enable swap space for the device. Check your available disks using the lsblk command.

[ec2-user ~]$ lsblk
NAME  MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
xvda1 202:1    0    8G  0 disk /
xvda3 202:3    0  896M  0 disk

Here, the swap volume xvda3 is available to the instance, but it is not enabled (notice that the MOUNTPOINT field is empty). You can enable the swap volume with the swapon command.

[ec2-user ~]$ sudo swapon /dev/xvda3

Now the swap space should show up in lsblk and swapon -s output.

[ec2-user ~]$ lsblk
NAME  MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
xvda1 202:1    0    8G  0 disk /
xvda3 202:3    0  896M  0 disk [SWAP]
[ec2-user ~]$ swapon -s
Filename                                Type            Size    Used    Priority
/dev/xvda3                              partition       917500  0       -1

You also need to edit your /etc/fstab file so that this swap space is automatically enabled at every system boot.

[ec2-user ~]$ sudo vim /etc/fstab

Append the following line to your /etc/fstab file (using the swap device name for your system):

/dev/xvda3       none    swap    sw  0       0

실제적으로 /etc/fstab 을 vi 로 조져보면 위에 있는 줄 말고 따른놈이 혼자 놀고 있는 것을 알 수 있다.

To use an instance store volume as swap space

Any instance store volume can be used as swap space. For example, the m3.medium instance type includes a 4 GB SSD instance store volume that is appropriate for swap space. If your instance store volume is much larger (for example, 350 GB), you may consider partitioning the volume with a smaller swap partition of 4-8 GB and the rest for a data volume.

1. List the block devices attached to your instance to get the device name for your instance store volume.

[ec2-user ~]$ lsblk -p
NAME       MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
/dev/xvdb  202:16   0   4G  0 disk /media/ephemeral0
/dev/xvda1 202:1    0   8G  0 disk /

In this example, the instance store volume is /dev/xdvb. Because this is an Amazon Linux instance, the instance store volume is formatted and mounted at /media/ephemeral0; not all Linux operating systems do this automatically.

2. (Optional) If your instance store volume is mounted (it lists a MOUNTPOINT in the lsblk command output), unmount it with the following command.

[ec2-user ~]$ sudo umount /dev/xvdb

EBS 가 mount 되어 있는 상태에서 시도해보려고 했는데 작동이 안되었던 부분이다. 이게 실제로 Optional 로 작용하는지는 모르겠는데, 일단 내 case 에서는 umount 를 해줘야 작동이 됬다.

3. Set up a Linux swap area on the device with the mkswap command.

[ec2-user ~]$ sudo mkswap /dev/xvdb
mkswap: /dev/xvdb: warning: wiping old ext3 signature.
Setting up swapspace version 1, size = 4188668 KiB
no label, UUID=b4f63d28-67ed-46f0-b5e5-6928319e620b

4. Enable the new swap space.

[ec2-user ~]$ sudo swapon /dev/xvdb

5. Verify that the new swap space is being used.

[ec2-user ~]$ swapon -s
Filename				Type		Size	Used	Priority
/dev/xvdb                              	partition	4188668	0	-1

6. Edit your /etc/fstab file so that this swap space is automatically enabled at every system boot.

[ec2-user ~]$ sudo vim /etc/fstab

If your /etc/fstab file has an entry for /dev/xvdb (or /dev/sdb) change it to match the line below; if it does not have an entry for this device, append the following line to your /etc/fstab file (using the swap device name for your system):

/dev/xvdb       none    swap    sw  0       0

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instance-store-swap-volumes.html

After you increase the size of an EBS volume, you must use file system–specific commands to extend the file system to the new, larger size. You can do this as soon as the volume enters the optimizing state.

To extend a file system on Linux, you need to:

Before you begin

Extend the file system of EBS volumes

Use the following procedure to extend the file system for a resized volume.

Note that device and partition naming differs for Xen instances and Nitro instances. To determine whether your instance is Xen-based or Nitro-based, use the describe-instance-types AWS CLI command as follows:

AWS CLI 에서 반드시 이부분을 확인하고 넘어가야한다. 부가적으로 설명하자면 t2 ~ t3 급에서 m5 급이나 c5 급 등으로 올라오게 되면 변경점이 생기기 때문이다

[ec2-user ~]$ aws ec2 describe-instance-types --instance-type instance_type --query "InstanceTypes[].Hypervisor"

nitro indicates that your instance in Nitro-based. xen or xen-on-nitro indicates that your instance is Xen-based.

To extend the file system of EBS volumes

1. Connect to your instance.
2. Resize the partition, if needed. To do so
   1. Check whether the volume has a partition. Use the lsblk command.
      
      Nitro Instance Example
      In the following example output, the root volume (nvme0n1) has two partitions (nvme0n1p1 and nvme0n1p128), while the additional volume (nvme1n1) has no partitions.

[ec2-user ~]$ sudo lsblk
NAME          MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
nvme1n1       259:0    0  30G  0 disk /data
nvme0n1       259:1    0  16G  0 disk
└─nvme0n1p1   259:2    0   8G  0 part /
└─nvme0n1p128 259:3    0   1M  0 part

Xen Instance Example

In the following example output, the root volume (xvda) has a partition (xvda1), while the additional volume (xvdf) has no partition.

[ec2-user ~]$ sudo lsblk                
NAME    MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
xvda    202:0    0  16G  0 disk
└─xvda1 202:1    0   8G  0 part /
xvdf    202:80   0  24G  0 disk

If the volume has a partition, continue the procedure from the following step (2b). If the volume has no partitions, skip steps 2b, 2c, and 2d, and continue the procedure from step 3.

이러한 부분에서 swap disk 를 생성해주려고 하는 경우에는 Instance 변경에 따라 문제가 생길 수 있기 때문에 option 으로 nvme 를 가져가게 된다

Extend the partition. Use the growpart command and specify the partition to extend.

Nitro Instance Example

For example, to extend a partition named nvme0n1p1, use the following command.

[ec2-user ~]$ sudo growpart /dev/nvme0n1 1

Xen Instance Example

For example, to extend a partition named xvda1, use the following command.

Important

Note the space between the device name (xvda) and the partition number (1).

[ec2-user ~]$ sudo growpart /dev/xvda 1

Verify that the partition has been extended. Use the lsblk command. The partition size should now be equal to the volume size.

확장된 부분에 대한 확인사살을 하면 된다

Nitro 인스턴스의 경우에는 아래처럼 1부터 파티션 128까지 붙을 수 있다

[ec2-user ~]$ sudo lsblk
NAME          MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
nvme1n1       259:0    0  30G  0 disk /data
nvme0n1       259:1    0  16G  0 disk
└─nvme0n1p1   259:2    0  16G  0 part /
└─nvme0n1p128 259:3    0   1M  0 part

아래의 경우는 Xen Instance 의 경우이다

[ec2-user ~]$ df -hT
Filesystem      Type   Size    Used   Avail   Use%   Mounted on
/dev/xvda1      ext4   8.0G    1.9G   6.2G    24%    /
/dev/xvdf1      xfs    24.0G   45M    8.0G    1%     /data
...

The commands to extend the file system differ depending on the file system type. Choose the following correct command based on the file system type that you noted in the previous step.

[ec2-user ~]$ sudo xfs_growfs -d /

[Ext4 file system] Use the resize2fs command and specify the name of the file system that you noted in the previous step.

Nitro instance example

For example, to extend a file system mounted named /dev/nvme0n1p1, use the following command.

[ec2-user ~]$ sudo resize2fs /dev/nvme0n1p1

Xen instance example

For example, to extend a file system mounted named /dev/xvda1, use the following command.

[ec2-user ~]$ sudo resize2fs /dev/xvda1

1. Verify that the file system has been extended. Use the df -hT command and confirm that the file system size is equal to the volume size.

You can share your AMIs with other AWS accounts. To allow all AWS accounts to use an AMI to launch instances, make the AMI public. To allow only specific accounts to use the AMI to launch instances, see Share an AMI with specific AWS accounts.

Considerations

Consider the following before making an AMI public.

Share an AMI with all AWS accounts (console)

After you make an AMI public, it is available in Community AMIs when you launch an instance in the same Region using the console. Note that it can take a short while for an AMI to appear in Community AMIs after you make it public. It can also take a short while for an AMI to be removed from Community AMIs after you make it private.

To share a public AMI using the console

1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.
2. In the navigation pane, choose AMIs.
3. Select your AMI from the list, and then choose Actions, Edit AMI permissions.
4. Choose Public, and then choose Save changes.

Share an AMI with all AWS accounts (AWS CLI)

Each AMI has a launchPermission property that controls which AWS accounts, besides the owner's, are allowed to use that AMI to launch instances. By modifying the launchPermission property of an AMI, you can make the AMI public (which grants launch permissions to all AWS accounts), or share it with only the AWS accounts that you specify.

You can add or remove account IDs from the list of accounts that have launch permissions for an AMI. To make the AMI public, specify the all group. You can specify both public and explicit launch permissions.

aws ec2 modify-image-attribute \
    --image-id ami-0abcdef1234567890 \
    --launch-permission "Add=[{Group=all}]"

2. To verify the launch permissions of the AMI, use the describe-image-attribute command.

aws ec2 describe-image-attribute \
    --image-id ami-0abcdef1234567890 \
    --attribute launchPermission

3. (Optional) To make the AMI private again, remove the all group from its launch permissions. Note that the owner of the AMI always has launch permissions and is therefore unaffected by this command.

aws ec2 modify-image-attribute \
    --image-id ami-0abcdef1234567890 \
    --launch-permission "Remove=[{Group=all}]"