Cloud

Startup Script

by Ulysses · Apr 6, 2021

Here’s how to run a script on bootup on Rhel 7 that’s running systemd.

First create a script. It this case, it will create a file called test.txt.

#!/bin/bash
> /root/test.txt

Make the script executable.

chmod /root/test.sh

Now create a service in /etc/systemd/system/test.service

# vi /etc/systemd/system/test.service
[Unit]
Description=A test service
After=network.target
[Service]
Type=simple
ExecStart=/root/test.sh
TimeoutStartSec=0
[Install]
WantedBy=default.target

Reload systemd.

systemctl daemon-reload

Enable the service.

systemctl enable test.service

Start the service.

systemctl start test.service

Reboot and test.

reboot

Validate if the script ran. Check if the file was created.

GCP 400 Bad Request

by Ulysses · Mar 15, 2021

After logging in, I tried to run Terraform in GCP and received this error:

oauth2: cannot fetch token: 400 Bad Request

Here’s the fix. Login using application-default.

gcloud auth application-default login

You can then Terraform.

terraform apply

AWS Get Account ID

by Ulysses · Mar 6, 2021

Here’s a quick way to find the AWS Account ID via AWS CLI.

aws sts get-caller-identity --query Account --output text

Output is a 12 digit number (redacted)

xxxxxxxxxxxx

AWS Account ID is a 12 digit number unique to each AWS account. Occasionally, there are scripts and policies that need the ID of the account. The command above is one way of querying the account ID so they can be used for policies that need them.

AWS Backup Vaults

by Ulysses · Mar 5, 2021

Here’s how to list AWS Backup vaults and plans. You can filter the output by specifying a vault.

aws backup list-backup-vaults --query "BackupVaultList[?BackupVaultName=='my-vault']" --output json

Output: (outputs are redacted for security reasons)

[
    {
        "BackupVaultName": "my-vault",
        "BackupVaultArn": "arn:aws:backup:us-east-1:xxxxxxxxxxxx:backup-vault:my-vault",
        "CreationDate": "2019-02-10T11:38:42.556000-05:00",
        "EncryptionKeyArn": "arn:aws:kms:us-east-1:xxxxxxxxxxxx:key/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
        "CreatorRequestId": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
        "NumberOfRecoveryPoints": 3
    }
]

Display the BackupPlanId of a specific backup plan.

aws backup list-backup-plans --query "BackupPlansList[?BackupPlanName=='my-backup-plan'].BackupPlanId"

Output: (outputs are redacted for security reasons)

[
    "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
]

GCP Add New Route

by Ulysses · Mar 2, 2021

Here’s how to add a new route in Google Cloud Platform.

gcloud compute routes create name-of-new-route \
  --destination-range=200.20.0.0/15 \
  --next-hop-gateway=default-internet-gateway \
  --project=host-project \
  --network="default" \
  --priority=900

AWS Copy AMI to another Region

by Ulysses · Mar 2, 2021

Here’s how to copy an AMI to another region.

aws ec2 copy-image \
  --source-image-id ami-xxxxxxxxxxx \
  --source-region us-east-1 \
  --region us-east-2 \
  --name "My DR server"

Output:

{
    "ImageId": "ami-xxxxxxxxxxx"
}

AWS Copy Snapshot to another Region

by Ulysses · Mar 2, 2021

If you need to copy a snapshot from one region to another, here’s the AWS CLI command.

aws ec2 copy-snapshot \
    --region us-east-1 \
    --source-region us-east-2 \
    --source-snapshot-id snap-xxxxxxxxxxxxxxxxx \
    --description "This is the DR snapshot copy"

Output:

{
    "SnapshotId": "snap-xxxxxxxxxxxxxxxxx"
}