diff --git a/website/source/docs/guides/acl-replication.md b/website/source/docs/guides/acl-replication.md new file mode 100644 index 000000000..1f4a5bd0a --- /dev/null +++ b/website/source/docs/guides/acl-replication.md @@ -0,0 +1,243 @@ +--- +name: 'ACL Replication for Multiple Datacenters' +content_length: 15 +id: acl-replication +layout: content_layout +products_used: + - Consul +description: Configure tokens, policies, and roles to work across multiple datacenters. +--- + +You can configure tokens, policies and roles to work across multiple datacenters. ACL replication has several benefits. + +1. It enables authentication of nodes and services between multiple datacenters. +1. The secondary datacenter can provide failover for all ACL components created in the primary datacenter. +1. Sharing policies reduces redundancy for the operator. + +## Prerequisites + +Before starting this guide, each datacenter will need to have ACLs enabled, the process is outlined in the [Securing Consul with ACLs +guide](/consul/security-networking/production-acls). This guide includes the additional ACL replication configuration for the Consul +agents not covered in the Securing Consul with ACL guide. + +Additionally, +[Basic Federation with WAN Gossip](/consul/security-networking/datacenters) is required. + +## Introduction + +In this guide, you will setup ACL replication. This is a multi-step process +that includes: + +- Setting the `primary_datacenter` parameter on all Consul agents in the primary datacenter. +- Creating the replication token. +- Configuring the `primary_datacenter` parameter on all Consul agents in the secondary datacenter. +- Enabling token replication on the servers in the secondary datacenter. +- Applying the replication token to all the servers in the secondary datacenter. + +You should complete this guide during the initial ACL bootstrapping +process. + +-> After ACLs are enabled you must have a privileged token to complete any +operation on either datacenter. You can use the initial +`bootstrap` token as your privileged token. + +## Configure the Primary Datacenter + +~> Note, if your primary datacenter uses the default `datacenter` name of +`dc1`, you must set a different `datacenter` parameter on each secondary datacenter. +Otherwise, both datacenters will be named `dc1` and there will be conflicts. + +### Consul Servers and Clients + +You should explicitly set the `primary_datacenter` parameter on all servers +and clients, even though replication is enabled by default on the primary +datacenter. Your agent configuration should be similar to the example below. + +```json +{ +"datacenter": "primary_dc", +"primary_datacenter": "primary_dc", +"acl": { + "enabled": true, + "default_policy": "deny", + "down_policy": "extend-cache", + "enable_token_persistence": true + } +} +``` + +The `primary_datacenter` +[parameter](https://www.consul.io/docs/agent/options.html#primary_datacenter) +sets the primary datacenter to have authority for all ACL information. It +should also be set on clients, so that the they can forward API +requests to the servers. + +Finally, start the agent. + +```sh +$ consul agent -config-file=server.json +``` + +Complete this process on all agents. If you are configuring ACLs for the +first time, you will also need to [compelete the bootstrapping process](/consul/security-networking/production-acls) now. + +## Create the Replication Token for ACL Management + +Next, create the replication token for managing ACLs +with the following privileges. + +- acl = "write" which will allow you to replicate tokens. +- operator = "read" for replicating proxy-default configuration entries. +- service_prefix, policy = "read" and intentions = "read" for replicating +service-default configuration entries, CA, and intention data. + +```hcl +acl = "write" + +operator = "read" + +service_prefix "" { + policy = "read" + intentions = "read" +} +``` + +Now that you have the ACL rules defined, create a policy with those rules. + +```sh +$ consul acl policy create -name replication -rules @replication-policy.hcl +ID: 240f1d01-6517-78d3-ec32-1d237f92ab58 +Name: replication +Description: Datacenters: +Rules: acl = "write" + +operator = "read" + +service_prefix "" { policy = "read" intentions = "read" } +``` + +Finally, use your newly created policy to create the replication token. + +```sh +$ consul acl token create description "replication token" -policy-name replication +AccessorID: 67d55dc1-b667-1835-42ab-64658d64a2ff +SecretID: fc48e84d-3f4d-3646-4b6a-2bff7c4aaffb +Description: replication token +Local: false +Create Time: 2019-05-09 18:34:23.288392523 +0000 UTC +Policies: + 240f1d01-6517-78d3-ec32-1d237f92ab58 - replication +``` + +## Enable ACL Replication on the Secondary Datacenter + +Once you have configured the primary datacenter and created the replication +token, you can setup the secondary datacenter. + +-> Note, your initial `bootstrap` token can be used for the necessary +privileges to complete any action on the secondary servers. + +### Configure the Servers + +You will need to set the `primary_datacenter` parameter to the name of your +primary datacenter and `enable_token_replication` to true on all the servers. + +```json +{ +"datacenter": "dc_secondary", +"primary_datacenter": "primary_dc", +"acl": { + "enabled": true, + "default_policy": "deny", + "down_policy": "extend-cache", + "enable_token_persistence": true, + "enable_token_replication": true + } +} +``` + +Now you can start the agent. + +```sh +$ consul agent -config-file=server.json +``` + +Repeat this process on all the servers. + +### Apply the Replication Token to the Servers + +Finally, apply the replication token to all the servers using the CLI. + +```sh +$ consul acl set-agent-token replication +ACL token "replication" set successfully +``` + +Once token replication has been enabled, you will also be able to create +datacenter local tokens. + +Repeat this process on all servers. If you are configuring ACLs for the +first time, you will also need to [set the agent token](/consul/security-networking/production-acls#add-the-token-to-the-agent). + +Note, the clients do not need the replication token. + +### Configure the Clients + +For the clients, you will need to set the `primary_datacenter` parameter to the +name of your primary datacenter and `enable_token_replication` to true. + +```json +{ +"datacenter": "dc_secondary", +"primary_datacenter": "primary_dc", +"acl": { + "enabled": true, + "default_policy": "deny", + "down_policy": "extend-cache", + "enable_token_persistence": true, + "enable_token_replication": true + } +} +``` + +Now you can start the agent. + +```sh +$ consul agent -config-file=server.json +``` + +Repeat this process on all clients. If you are configuring ACLs for the +first time, you will also need to [set the agent token](/consul/security-networking/production-acls#add-the-token-to-the-agent). + +## Check Replication + +Now that you have set up ACL replication, you can use the [HTTP API](https://www.consul.io/api/acl/acl.html#check-acl-replication) to check +the configuration. + +```sh +$ curl http://localhost:8500/v1/acl/replication?pretty +{ + "Enabled":true, + "Running":true, + "SourceDatacenter":"primary_dc", + "ReplicationType":"tokens", + "ReplicatedIndex":19, + "ReplicatedTokenIndex":22, + "LastSuccess":"2019-05-09T18:54:09Z", + "LastError":"0001-01-01T00:00:00Z" +} +``` + +Notice, the "ReplicationType" should be "tokens". This means tokens, policies, +and roles are being replicated. + +## Summary + +In this guide you setup token replication on multiple datacenters. You can complete this process on an existing datacenter, with minimal +modifications. Mainly, you will need to restart the Consul agent when updating +agent configuration with ACL parameters. + +If you have not configured other secure features of Consul, +[certificates](consul/security-networking/certificates) and +[encryption](consul/security-networking/agent-encryption), +we recommend doing so now.