Archives for August 2019

August 31, 2019

Remove Key from known_hosts

If you’ve changed keys, you will need to delete a ssh key from /etc/known_hosts file.

You can edit it manually using an editor such as vi or vim.

vim ~/.ssh/known_hosts

Or you can use ssh-keygen command with -R option to delete the hostname or IP address.

ssh-keygen -f "~/.ssh/known_hosts" -R "xxx.xxx.xxx.xxx"

August 30, 2019

Copy Files Using Rsync

Here’s how to copy files from one directory to another.

rsync -arvz /dir1 /dir2 >> /tmp/rsync.log &

Format: rsynch –options source destination

Options

-a archive mode
-v verbose
-p keep permissions
-z zipped during transfer
-r recursive

August 29, 2019

AWS RDS Start and Stop Policy

Here’s a IAM policy that you can add to an IAM user or an IAM role so they are able to start and stop a specific RDS instance.

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Condition": {
                "StringEqualsIgnoreCase": {
                    "rds:db-tag/Application": "application-name"
                }
            },
            "Action": [
                "rds:DescribeDBInstances",
                "rds:StartDBInstance",
                "rds:StopDBInstance"
            ],
            "Resource": "arn:aws:rds:us-east-1:xxxxxxxxxxxx:db:db-instance-name",
            "Effect": "Allow"
        }
    ]
}