rdspg

Command-line toolkit to help understand information about your AWS RDS Parameter Groups.

Installation

pip install rdspg

Purpose

When it comes to analyzing parameter groups for RDS, AWS suggested in a blog post that it could only be done using diff:

There is no AWS CLI command to compare two parameter groups simultaneously; this feature is only available by using the RDS console. You can then compare the plain text files that list the parameter groups using a Linux tool such as the diff command, or a source code editor like Notepad++.

I think we can do better. This tool is to help us make that task a lot easier. Also adding a few other features to help analyzing changes.

Permission Config

This tool needs certain IAM permissions in order to work. Example policy:

{
   "Version":"2012-10-17",
   "Statement":[
      {
         "Effect":"Allow",
         "Action":[
            "rds:DescribeDBInstances",
            "rds:DescribeDBParameters",
            "rds:DescribeDBParameterGroups",
            "rds:DescribeDBClusters",
            "rds:DescribeDBClusterParameterGroups",
            "rds:DescribeDBClusterParameters",
            "rds:ListTagsForResource"
         ],
         "Resource":"*"
      }
   ]
}

Usage

• Listing Parameter Groups:

$ rdspg list
DBParameterGroupName             DBParameterGroupFamily    Description
-------------------------------  ------------------------  ----------------------------------------------------------
default.aurora-postgresql9.6     aurora-postgresql9.6      Default parameter group for aurora-postgresql9.6
default.aurora5.6                aurora5.6                 Default parameter group for aurora5.6
default.postgres9.3              postgres9.3               Default parameter group for postgres9.3
default.postgres9.4              postgres9.4               Default parameter group for postgres9.4
default.postgres9.5              postgres9.5               Default parameter group for postgres9.5
default.postgres9.6              postgres9.6               Default parameter group for postgres9.6
my-parameter-group               postgres9.6               My Parameter Group

• Getting parameters in parameter group, filtering out default values:

$ rdspg get my-replica
ParameterName                      ParameterValue  ApplyMethod    ApplyType
-------------------------------  ----------------  -------------  -----------
autovacuum_analyze_scale_factor               0.1  immediate      dynamic
checkpoint_segments                           512  immediate      dynamic
checkpoint_timeout                            300  immediate      dynamic
checkpoint_warning                             60  immediate      dynamic
default_statistics_target                     100  immediate      dynamic
hot_standby_feedback                            1  immediate      dynamic
log_autovacuum_min_duration                     0  immediate      dynamic
log_connections                                 1  immediate      dynamic
log_disconnections                              1  immediate      dynamic

• Getting a mapping of parameter group -> instances:

$ rdspg mapping
ParameterGroup       DBInstances
-------------------  ---------------------------------
default.postgres9.4  <not-used>
default.postgres9.5  db-replica-9-5-a,db-replica-9-5-b
default.postgres9.6  db-replica-9-6-a,db-replica-9-6-b

• Compare differences between two parameter groups:

$ rdspg diff my-replica-a my-replica-b
ParameterName          my-replica-a  my-replica-b
-------------------  --------------  ---------------------
checkpoint_timeout              300  450
checkpoint_warning               60  <not-set>
checkpoint_segments             512  32

• Export parameter group in terraform template format:

$ rdspg terraform my-parameter-group
resource "aws_db_parameter_group" "my-parameter-group" {
  name   = "my-parameter-group"
  family = "postgres9.5"
  description = "My awesome parameter group"

  parameter {
    name         = "autovacuum_analyze_scale_factor"
    value        = "0.01"
    apply_method = "immediate"
  }

  parameter {
    name         = "autovacuum_vacuum_scale_factor"
    value        = "0.01"
    apply_method = "immediate"
  }

}

• All the commands work for db clusters with --cluster flag

$ rdspg list --cluster
DBClusterParameterGroupName    DBParameterGroupFamily    Description
-----------------------------  ------------------------  --------------------------------------------------------
customers-p-cluster            aurora-postgresql9.6      Managed by Terraform
default.aurora-postgresql1     aurora-postgresql1        Default cluster parameter group for aurora-postgresql1
default.aurora-postgresql9.6   aurora-postgresql9.6      Default cluster parameter group for aurora-postgresql9.6
default.aurora5.6              aurora5.6                 Default cluster parameter group for aurora5.6