Uly.me

cloud engineer

Archives for March 2021

Set Timezone Permanently

It’s recommended to set the clock to UTC. In rare occasions, local time may be needed.

Here’s how to set your server’s timezone permanently.

Check the date first.

date

Backup localtime. Set it to US Eastern Time.

mv /etc/localtime /etc/localtime.backup
ln -s /usr/share/zoneinfo/America/New_York /etc/localtime

Backup clock. Set it to US Eastern Time.

cp -p /etc/sysconfig/clock /etc/sysconfig/clock.backup 
> /etc/sysconfig/clock
echo ZONE=\"America/New_York\" > /etc/sysconfig/clock

Run the date again to validate.

date

BitWarden

I changed password managers from LastPass to BitWarden the other day. Migrating your credentials requires exporting and importing a CSV file from one program to another. It was an easy transition. Everything seems to work. As you may be aware, LastPass decided to make their free account limited to just one device. Customers will need to choose which device to use, whether desktop or mobile. Not both. If you want it on multiple devices, you’ll need to fork up $3 per month. It is not that expensive, but there are other alternatives. A few recommend BitWarden. It will let you sync to all devices for free. It was an easy choice.

GCP Cloud Shell Vim Settings

I had an issue with using the backspace in Vim in GCP’s Cloud Shell. Every time I’m in the insert mode and I want to edit using backspace, it doesn’t delete the characters. It shows these characters “^?” instead. Well, it turned out to be a backspace setting that you can set within .vimrc. So, here’s my working setup.

colo desert
syntax on
set backspace=indent,eol,start
set nocompatible
  • The first line uses the desert theme.
  • The second line turns on syntax highlighting. It’s on by default.
  • The third line fixes the backspace issue I mentioned above.

AWS Backup Setup

This script creates an AWS backup vault, adds a backup plan and a backup selection.

Set up profile, region and Account ID first.

#!/bin/bash
profile="default"
region="us-east-1"
id=$(aws sts get-caller-identity --query Account --output text)

Create a vault.

aws backup create-backup-vault \
--backup-vault-name my-vault \
--profile $profile \
--region $region

Create a backup plan.

aws backup create-backup-plan \
--backup-plan file://back-plan.json \ 
--profile $profile \
--region $region

backup-plan.json

{
    "BackupPlan": {
        "BackupPlanName": "efs-0000",
        "Rules": [
            {
                "RuleName": "efs-0000",
                "TargetBackupVaultName": "my-vault",
                "ScheduleExpression": "cron(0 0 ? * * *)",
                "StartWindowMinutes": 60,
                "CompletionWindowMinutes": 10080,
                "Lifecycle": {
                    "DeleteAfterDays": 7
                }
            }
        ]
    }
}

Get the backup plan ID.

planid=$(aws backup list-backup-plans \
  --query "BackupPlansList[?BackupPlanName=='efs-0000'].BackupPlanId" \
  --profile $profile \
  --region $region \
  --output text)

Create a backup selection.

# Create a backup selection
aws backup create-backup-selection \
--backup-plan-id $planid \
--cli-input-json file://backup-selection.json \
--profile $profile \
--region $region

backup-selection.json

{
    "BackupSelection": {
		"SelectionName": "efs-0000",
        "IamRoleArn": "arn:aws:iam::xxxxxxxxxxxx:role/service-role/AWSBackupDefaultServiceRole",
        "Resources": [],
        "ListOfTags": [
            {
                "ConditionType": "STRINGEQUALS",
                "ConditionKey": "aws-backup",
                "ConditionValue": "efs-0000"
            }
        ]
    }
}

The enable EFS backup, add a tag key of aws-backup with a value of efs-0000.

AWS Backup Vaults

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"
]

Count String Characters

Here’s a simple little script that displays the number of characters in a string.

#!/bin/bash
if [[ $# -eq 0 ]] ; then echo 'Missing arguments'; exit 0; fi
var=$1
size=${#var}
echo $size

Command:

./length.sh abcdefghijklmnopqrstuvwxyz

Output:

26