c7n-org: Multi Account Custodian Execution¶
c7n-org is a tool to run Custodian against multiple AWS accounts, Azure subscriptions, GCP projects, or OCI tenancies in parallel.
Installation¶
pip install c7n-org
c7n-org has 3 run modes:
Usage: c7n-org [OPTIONS] COMMAND [ARGS]...
custodian organization multi-account runner.
Options:
--help Show this message and exit.
Commands:
report report on an AWS cross account policy execution
run run a custodian policy across accounts (AWS, Azure, GCP, OCI)
run-script run a script across AWS accounts
In order to run c7n-org against multiple accounts, a config file must first be created containing pertinent information about the accounts:
Example AWS Config File:
accounts:
- account_id: '123123123123'
name: account-1
regions:
- us-east-1
- us-west-2
role: arn:aws:iam::123123123123:role/CloudCustodian
vars:
charge_code: xyz
tags:
- type:prod
- division:some division
- partition:us
- scope:pci
...
Example Azure Config File:
subscriptions:
- name: Subscription-1
subscription_id: a1b2c3d4-e5f6-g7h8i9...
- name: Subscription-2
subscription_id: 1z2y3x4w-5v6u-7t8s9r...
Example GCP Config File:
projects:
- name: app-dev
project_id: app-203501
tags:
- label:env:dev
- name: app-prod
project_id: app-1291
tags:
- label:env:dev
Example OCI Config File:
tenancies:
- name: dev-tenancy
profile: DEVTENANCY
regions:
- us-ashburn-1
- us-phoenix-1
vars:
environment: dev
tags:
- type:test
...
Config File Generation¶
We also distribute scripts to generate the necessary config file in the scripts
folder.
Note: Currently these are distributed only via git. Per https://github.com/cloud-custodian/cloud-custodian/issues/2420, we’ll be looking to incorporate them into a new c7n-org subcommand.
For AWS, the script
orgaccounts.py
generates a config file from the AWS Organizations API.
python orgaccounts.py -f accounts.yml
For Azure, the script
azuresubs.py
generates a config file from the Azure Resource Management API.Please see the Additional Azure Instructions for initial setup and other important info.
python azuresubs.py -f subscriptions.yml
For GCP, the script
gcpprojects.py
generates a config file from the GCP Resource Management API.
python gcpprojects.py -f projects.yml
For OCI, the script
ocitenancies.py
generates a config file using OCI Configuration file and OCI Organizations API.Please refer to the Additional OCI Instructions for additional information.
python ocitenancies.py -f tenancies.yml
Running a Policy with c7n-org¶
To run a policy, the following arguments must be passed in:
-c | accounts|projects|subscriptions|tenancies config file
-s | output directory
-u | policy
For example:
c7n-org run -c accounts.yml -s output -u test.yml --dryrun
After running the above command, the following folder structure will be created:
output
|_ account-1
|_ us-east-1
|_ policy-name
|_ resources.json
|_ custodian-run.log
|_ us-west-2
|_ policy-name
|_ resources.json
|_ custodian-run.log
|- account-2
...
Use c7n-org report
to generate a csv report from the output directory.
Selecting accounts, regions, policies for execution¶
You can filter the accounts to be run against by either passing the
account name or id via the -a
flag, which can be specified multiple
times, or alternatively with comma separated values.
Groups of accounts can also be selected for execution by specifying
the -t
tag filter. Account tags are specified in the config
file. Given the above accounts config file, you can specify all prod
accounts with -t type:prod
. You can specify the -t
flag multiple
times or use a comma separated list.
You can specify which policies to use for execution by either
specifying -p
or selecting groups of policies via their tags with
-l
. Both options support being specified multiple times or using
comma separated values.
By default in AWS, c7n-org will execute in parallel across regions.
The -r
flag can be specified multiple times and defaults to
(us-east-1, us-west-2)
. A special value of all
will execute across
all regions.
See c7n-org run --help
for more information.
Defining and using variables¶
Each account/subscription/project configuration in the config file can
also define a variables section vars
that can be used in policies’
definitions and are interpolated at execution time. These are in
addition to the default runtime variables custodian provides like
account_id
, now
, and region
.
Example of defining in c7n-org config file:
accounts:
- account_id: '123123123123'
name: account-1
role: arn:aws:iam::123123123123:role/CloudCustodian
vars:
charge_code: xyz
Example of using in a policy file:
policies:
- name: ec2-check-tag
resource: aws.ec2
filters:
- "tag:CostCenter": "{charge_code}"
Another enhancement for c7n-org run-script
is to support a few vars in the script arg.
The available vars are account
, account_id
, region
and output_dir
.
c7n-org run-script -s . -c my-projects.yml gcp_check_{region}.sh
# or
c7n-org run-script -s . -c my-projects.yml use_another_policy_result.sh {output_dir}
Note: Variable interpolation is sensitive to proper quoting and spacing,
i.e., { charge_code }
would be invalid due to the extra white space. Additionally,
yaml parsing can transform a value like {charge_code}
to null, unless it’s quoted
in strings like the above example. Values that do interpolation into other content
don’t require quoting, i.e., “my_{charge_code}”.
Other commands¶
c7n-org also supports running arbitrary scripts against accounts via
the run-script command. For AWS the standard AWS SDK credential
information is exported into the process environment before executing.
For Azure and GCP, only the environment variables
AZURE_SUBSCRIPTION_ID
and PROJECT_ID
are exported(in addition of
the system env variables).
c7n-org also supports generating reports for a given policy execution
across accounts via the c7n-org report
subcommand. By default,
account_id is not exposed to the output, but you may append it by
using --field AccountID=account_id
in the cli.
Additional Azure Instructions¶
If you’re using an Azure Service Principal for executing c7n-org you’ll need to ensure that the principal has access to multiple subscriptions.
For instructions on creating a service principal and granting access across subscriptions, visit the Azure authentication docs page.
Additional OCI Instructions¶
The script ocitenancies.py
accepts an optional argument --add-child-tenancies
which adds all the child tenancies associated with the DEFAULT
profile’s tenancy
in the generated c7n-org configuration file. If the profile for child tenancy is not available in
the OCI configuration file, then either user can add the profile for the child tenancy to the
OCI configuration file and replace the <ADD_PROFILE>
entry in the c7n-org configuration with the
corresponding profile name or the user can delete the child tenancy entry from the
c7n-org configuration file. For more info about config file, refer to this page.
If the user wants to query for the resources in the specific compartments in c7n-org, then the user
can pass the compartment OCID’s to the oci_compartments
under the vars
section like below. If the
oci_comparments
is not passed under vars
, then the resources will be fetched from the tenancy level.
tenancies:
- name: dev-tenancy
profile: DEVTENANCY
regions:
- us-ashburn-1
- us-phoenix-1
vars:
oci_compartments: ocid1.test.oc1..<unique_ID>EXAMPLE-compartmentId-2-Value,ocid1.test.oc1..<unique_ID>EXAMPLE-compartmentId-3-Value
environment: dev
- name: test-tenancy
profile: TESTTENANCY
regions:
- us-ashburn-1
vars:
environment: test