Consul

This Ansible role installs Consul, including establishing a filesystem structure and server or client agent configuration with support for some common operational features.

It can also bootstrap a development or evaluation cluster of 3 server agents running in a Vagrant and VirtualBox based environment. See README_VAGRANT.md and the associated Vagrantfile for more details.

Role Philosophy

“Another flaw in the human character is that everybody wants to build and nobody wants to do maintenance.”
― Kurt Vonnegut, Hocus Pocus

Please note that the original design goal of this role was more concerned with the initial installation and bootstrapping of a Consul server cluster environment and so it does not currently concern itself (all that much) with performing ongoing maintenance of a cluster.

Many users have expressed that the Vagrant based environment makes getting a working local Consul server cluster environment up and running an easy process — so this role will target that experience as a primary motivator for existing.

If you get some mileage from it in other ways, then all the better!

Role migration and installation

This role was originally developed by Brian Shumate and was known on Ansible Galaxy as brianshumate.consul. Brian asked the community to be relieved of the maintenance burden, and therefore Bas Meijer transferred the role to ansible-community so that a team of volunteers can maintain it. At the moment there is no membership of ansible-community on https://galaxy.ansible.com and therefore to install this role into your project you should create a file requirements.yml in the subdirectory roles/ of your project with this content:

---
- src: https://github.com/ansible-community/ansible-consul.git
  name: ansible-consul
  scm: git
  version: master

This repo has tagged releases that you can use to pin the version.

Tower will install the role automatically, if you use the CLI to control ansible, then install it like:

ansible-galaxy install -p roles -r roles/requirements.yml

Requirements

This role requires a FreeBSD, Debian, or Red Hat Enterprise Linux distribution or Windows Server 2012 R2.

The role might work with other OS distributions and versions, but is known to function well with the following software versions:

• Consul: 1.8.7
• Ansible: 2.8.2
• Alma Linux: 8, 9
• Alpine Linux: 3.8
• CentOS: 7, 8
• Debian: 9
• FreeBSD: 11
• Mac OS X: 10.15 (Catalina)
• RHEL: 7, 8
• Rocky Linux: 8
• OracleLinux: 7, 8
• Ubuntu: 16.04
• Windows: Server 2012 R2

Note that for the "local" installation mode (the default), this role will locally download only one instance of the Consul archive, unzip it and install the resulting binary on all desired Consul hosts.

To do so requires that unzip is available on the Ansible control host and the role will fail if it doesn't detect unzip in the PATH.

Collection requirements for this role are listed in the requirements.yml file. It is your responsibility to make sure that you install these collections to ensure that the role runs properly. Usually, this can be done with:

ansible-galaxy collection install -r requirements.yml

Caveats

This role does not fully support the limit option (ansible -l) to limit the hosts, as this will break populating required host variables. If you do use the limit option with this role, you can encounter template errors like:

Undefined is not JSON serializable.

Role Variables

The role uses variables defined in these 3 places:

• Hosts inventory file (see examples/vagrant_hosts for an example)
• vars/*.yml (primarily OS/distributions specific variables)
• defaults/main.yml (everything else)

⚠️ NOTE: The role relies on the inventory host group for the consul servers to be defined as the variable consul_group_name and it will not function properly otherwise. Alternatively the consul servers can be placed in the default host group [consul_instances] in the inventory as shown in the examples below.

Many role variables can also take their values from environment variables as well; those are noted in the description where appropriate.

consul_version

• Version to install
• Set value as latest for the latest available version of consul
• Default value: 1.8.7

consul_architecture_map

• Dictionary for translating ansible_architecture values to Go architecture values naming convention
• Default value: dict

consul_architecture

• System architecture as determined by {{ consul_architecture_map[ansible_architecture] }}
• Default value (determined at runtime): amd64, arm, or arm64

consul_os

• Operating system name in lowercase representation
• Default value: {{ ansible_os_family | lower }}

consul_install_dependencies

• Install python and package dependencies required for the role functions.
• Default value: true

consul_zip_url

• Consul archive file download URL
• Default value: https://releases.hashicorp.com/consul/{{ consul_version }}/consul_{{ consul_version }}_{{ consul_os }}_{{ consul_architecture }}.zip

consul_checksum_file_url

• Package SHA256 summaries file URL
• Default value: https://releases.hashicorp.com/consul/{{ consul_version }}/{{ consul_version }}_SHA256SUMS

consul_bin_path

• Binary installation path
• Default Linux value: /usr/local/bin
• Default Windows value: C:\ProgramData\consul\bin

consul_config_path

• Base configuration file path
• Default Linux value: /etc/consul
• Default Windows value: C:\ProgramData\consul\config

consul_configd_path

• Additional configuration directory
• Default Linux value: {{ consul_config_path }}/consul.d
• Default Windows value: C:\ProgramData\consul\config.d

consul_data_path

• Data directory path as defined in data_dir or -data-dir
• Default Linux value: /opt/consul
• Default Windows value: C:\ProgramData\consul\data

consul_configure_syslogd

• Enable configuration of rsyslogd or syslog-ng on Linux. If disabled, Consul will still log to syslog if consul_syslog_enable is true, but the syslog daemon won't be configured to write Consul logs to their own logfile.
  • Override with CONSUL_CONFIGURE_SYSLOGD environment variable
• Default Linux value: false

consul_log_path

• If consul_syslog_enable is false
  • Log path for use in log_file or -log-file
• If consul_syslog_enable is true
  • Log path for use in rsyslogd configuration on Linux. Ignored if consul_configure_syslogd is false.
• Default Linux value: /var/log/consul
  • Override with CONSUL_LOG_PATH environment variable
• Default Windows value: C:\ProgramData\consul\log

consul_log_file

• If consul_syslog_enable is false
  • Log file for use in log_file or -log-file
• If consul_syslog_enable is true
  • Log file for use in rsyslogd configuration on Linux. Ignored if consul_configure_syslogd is false.
• Override with CONSUL_LOG_FILE environment variable
• Default Linux value: consul.log

consul_log_rotate_bytes

• Log rotate bytes as defined in log_rotate_bytes or -log-rotate-bytes
  • Override with CONSUL_LOG_ROTATE_BYTES environment variable
• Ignored if consul_syslog_enable is true
• Default value: 0

consul_log_rotate_duration

• Log rotate bytes as defined in log_rotate_duration or -log-rotate-duration
  • Override with CONSUL_LOG_ROTATE_DURATION environment variable
• Ignored if consul_syslog_enable is true
• Default value: 24h

consul_log_rotate_max_files

• Log rotate bytes as defined in log_rotate_max_files or -log-rotate-max-files
  • Override with CONSUL_LOG_ROTATE_MAX_FILES environment variable
• Ignored if consul_syslog_enable is true
• Default value: 0

consul_syslog_facility

• Syslog facility as defined in syslog_facility
  • Override with CONSUL_SYSLOG_FACILITY environment variable
• Default Linux value: local0

syslog_user

• Owner of rsyslogd process on Linux. consul_log_path's ownership is set to this user on Linux. Ignored if consul_configure_syslogd is false.
  • Override with SYSLOG_USER environment variable
• Default Linux value: syslog

syslog_group

• Group of user running rsyslogd process on Linux. consul_log_path's group ownership is set to this group on Linux. Ignored if consul_configure_syslogd is false.
  • Override with SYSLOG_GROUP environment variable
• Default value: adm

consul_run_path

• Run path for process identifier (PID) file
• Default Linux value: /run/consul
• Default Windows value: C:\ProgramData\consul

consul_user

• OS user
• Default Linux value: consul
• Default Windows value: LocalSystem

consul_manage_user

• Whether to create the user defined by consul_user or not
• Default value: true

consul_group

• OS group
• Default value: bin

consul_manage_group

• Whether to create the group defined by consul_group or not
• Default value: true

consul_group_name

• Inventory group name
  • Override with CONSUL_GROUP_NAME environment variable
• Default value: consul_instances

consul_retry_interval

• Interval for reconnection attempts to LAN servers
• Default value: 30s

consul_retry_interval_wan

• Interval for reconnection attempts to WAN servers
• Default value: 30s

consul_retry_join_skip_hosts

• If true, the config value for retry_join won't be populated by the default hosts servers. The value can be initialized using consul_join
• Default value: false

consul_retry_max

• Max reconnection attempts to LAN servers before failing (0 = infinite)
• Default value: 0

consul_retry_max_wan

• Max reconnection attempts to WAN servers before failing (0 = infinite)
• Default value: 0

consul_join

• List of LAN servers, not managed by this role, to join (IPv4 IPv6 or DNS addresses)
• Default value: []

consul_join_wan

• List of WAN servers, not managed by this role, to join (IPv4 IPv6 or DNS addresses)
• Default value: []

consul_servers

It's typically not necessary to manually alter this list.

• List of server nodes
• Default value: List of all nodes in consul_group_name with consul_node_role set to server or bootstrap

consul_bootstrap_expect

• Boolean that adds bootstrap_expect value on Consul servers's config file
• Default value: false

consul_bootstrap_expect_value

• Integer to define the minimum number of consul servers joined to the cluster in order to elect the leader.
• Default value: Calculated at runtime based on the number of nodes

consul_gather_server_facts

This feature makes it possible to gather the consul_advertise_address(_wan) from servers that are currently not targeted by the playbook.

To make this possible the delegate_facts option is used; note that his option has been problematic.

• Gather facts from servers that are not currently targeted
• Default value: false

consul_datacenter

• Datacenter label
  • Override with CONSUL_DATACENTER environment variable- Default value: dc1
• Default value: dc1

consul_domain

• Consul domain name as defined in domain or -domain
  • Override with CONSUL_DOMAIN environment variable
• Default value: consul

consul_alt_domain

• Consul domain name as defined in alt_domain or -alt-domain
  • Override with CONSUL_ALT_DOMAIN environment variable
• Default value: Empty string

consul_node_meta

• Consul node meta data (key-value)
• Supported in Consul version 0.7.3 or later
• Default value: {}
• Example:

consul_node_meta:
    node_type: "my-custom-type"
    node_meta1: "metadata1"
    node_meta2: "metadata2"

consul_log_level

• Log level as defined in log_level or -log-level
  • Override with CONSUL_LOG_LEVEL environment variable
• Default value: INFO

consul_syslog_enable

• Log to syslog as defined in enable_syslog or -syslog
  • Override with CONSUL_SYSLOG_ENABLE environment variable
• Default Linux value: false
• Default Windows value: false

consul_iface

• Consul network interface
  • Override with CONSUL_IFACE environment variable
• Default value: {{ ansible_default_ipv4.interface }}

consul_bind_address

• Bind address
  • Override with CONSUL_BIND_ADDRESS environment variable
• Default value: default ipv4 address, or address of interface configured by consul_iface

consul_advertise_address

• LAN advertise address
• Default value: consul_bind_address

consul_advertise_address_wan

• Wan advertise address
• Default value: consul_bind_address

consul_translate_wan_address

• Prefer a node's configured WAN address when serving DNS
• Default value: false

consul_advertise_addresses

• Advanced advertise addresses settings
• Individual addresses can be overwritten using the consul_advertise_addresses_* variables
• Default value:

  consul_advertise_addresses:
    serf_lan: "{{ consul_advertise_addresses_serf_lan | default(consul_advertise_address+':'+consul_ports.serf_lan) }}"
    serf_wan: "{{ consul_advertise_addresses_serf_wan | default(consul_advertise_address_wan+':'+consul_ports.serf_wan) }}"
    rpc: "{{ consul_advertise_addresses_rpc | default(consul_bind_address+':'+consul_ports.server) }}"

consul_client_address

• Client address
• Default value: 127.0.0.1

consul_addresses

• Advanced address settings
• Individual addresses kan be overwritten using the consul_addresses_* variables
• Default value:

  consul_addresses:
    dns: "{{ consul_addresses_dns | default(consul_client_address, true) }}"
    http: "{{ consul_addresses_http | default(consul_client_address, true) }}"
    https: "{{ consul_addresses_https | default(consul_client_address, true) }}"
    rpc: "{{ consul_addresses_rpc | default(consul_client_address, true) }}"
    grpc: "{{ consul_addresses_grpc | default(consul_client_address, true) }}"
    grpc_tls: "{{ consul_addresses_grpc_tls | default(consul_client_address, true) }}"

consul_ports

• The official documentation on the Ports Used
• The ports mapping is a nested dict object that allows setting the bind ports for the following keys:
  • dns - The DNS server, -1 to disable. Default 8600.
  • http - The HTTP API, -1 to disable. Default 8500.
  • https - The HTTPS API, -1 to disable. Default -1 (disabled).
  • rpc - The CLI RPC endpoint. Default 8400. This is deprecated in Consul 0.8 and later.
  • grpc - The gRPC endpoint, -1 to disable. Default -1 (disabled).
  • grpc_tls - The gRPC TLS endpoint, -1 to disable. Default -1 (disabled). This is available in Consul 1.14.0 and later.
  • serf_lan - The Serf LAN port. Default 8301.
  • serf_wan - The Serf WAN port. Default 8302.
  • server - Server RPC address. Default 8300.

For example, to enable the consul HTTPS API it is possible to set the variable as follows:

• Default values:

  consul_ports:
    dns: "{{ consul_ports_dns | default('8600', true) }}"
    http: "{{ consul_ports_http | default('8500', true) }}"
    https: "{{ consul_ports_https | default('-1', true) }}"
    rpc: "{{ consul_ports_rpc | default('8400', true) }}"
    serf_lan: "{{ consul_ports_serf_lan | default('8301', true) }}"
    serf_wan: "{{ consul_ports_serf_wan | default('8302', true) }}"
    server: "{{ consul_ports_server | default('8300', true) }}"
    grpc: "{{ consul_ports_grpc | default('-1', true) }}"
    grpc_tls: "{{ consul_ports_grpc_tls | default('-1', true) }}"

Notice that the dict object has to use precisely the names stated in the documentation! And all ports must be specified. Overwriting one or multiple ports can be done using the consul_ports_* variables.

consul_node_name

• Define a custom node name (should not include dots) See node_name
  • The default value on Consul is the hostname of the server.
• Default value: ''

consul_recursors

• List of upstream DNS servers See recursors
  • Override with CONSUL_RECURSORS environment variable
• Default value: Empty list

consul_iptables_enable

• Whether to enable iptables rules for DNS forwarding to Consul
  • Override with CONSUL_IPTABLES_ENABLE environment variable
• Default value: false

consul_acl_policy

• Add basic ACL config file
  • Override with CONSUL_ACL_POLICY environment variable
• Default value: false

consul_acl_enable

• Enable ACLs
  • Override with CONSUL_ACL_ENABLE environment variable
• Default value: false

consul_acl_ttl

• TTL for ACL's
  • Override with CONSUL_ACL_TTL environment variable
• Default value: 30s

consul_acl_token_persistence

• Define if tokens set using the API will be persisted to disk or not
  • Override with CONSUL_ACL_TOKEN_PERSISTENCE environment variable
• Default value: true

consul_acl_datacenter

• ACL authoritative datacenter name
  • Override with CONSUL_ACL_DATACENTER environment variable
• Default value: {{ consul_datacenter }} (dc1)

consul_acl_down_policy

• Default ACL down policy
  • Override with CONSUL_ACL_DOWN_POLICY environment variable
• Default value: allow

consul_acl_token

• Default ACL token, only set if provided
  • Override with CONSUL_ACL_TOKEN environment variable
• Default value: ''

consul_acl_agent_token

• Used for clients and servers to perform internal operations to the service catalog. See: acl_agent_token
  • Override with CONSUL_ACL_AGENT_TOKEN environment variable
• Default value: ''

consul_acl_agent_master_token

• A special access token that has agent ACL policy write privileges on each agent where it is configured
  • Override with CONSUL_ACL_AGENT_MASTER_TOKEN environment variable
• Default value: ''

consul_acl_default_policy

• Default ACL policy
  • Override with CONSUL_ACL_DEFAULT_POLICY environment variable
• Default value: allow

consul_acl_master_token

• ACL master token
  • Override with CONSUL_ACL_MASTER_TOKEN environment variable
• Default value: UUID

consul_acl_master_token_display

• Display generated ACL Master Token
  • Override with CONSUL_ACL_MASTER_TOKEN_DISPLAY environment variable
• Default value: false

consul_acl_replication_enable

• Enable ACL replication without token (makes it possible to set the token trough the API)
  • Override with CONSUL_ACL_REPLICATION_TOKEN_ENABLE environment variable
• Default value: ''

consul_acl_replication_token

• ACL replication token
  • Override with CONSUL_ACL_REPLICATION_TOKEN_DISPLAY environment variable
• Default value: SN4K3OILSN4K3OILSN4K3OILSN4K3OIL

consul_tls_enable

• Enable TLS
  • Override with CONSUL_ACL_TLS_ENABLE environment variable
• Default value: false

consul_tls_copy_keys

• Enables or disables the management of the TLS files
  • Disable it if you enable TLS (consul_tls_enable) but want to manage the TLS files on your own
• Default value: true

consul_tls_dir

• Target directory for TLS files
  • Override with CONSUL_TLS_DIR environment variable
• Default value: /etc/consul/ssl

consul_tls_ca_crt

• CA certificate filename
  • Override with CONSUL_TLS_CA_CRT environment variable
• Default value: ca.crt

consul_tls_server_crt

• Server certificate
  • Override with CONSUL_TLS_SERVER_CRT environment variable
• Default value: server.crt

consul_tls_server_key

• Server key
  • Override with CONSUL_TLS_SERVER_KEY environment variable
• Default value: server.key

consul_tls_files_remote_src

• Copy from remote source if TLS files are already on host
• Default value: false

consul_encrypt_enable

• Enable Gossip Encryption
• Default value: true

consul_encrypt_verify_incoming

• Verify incoming Gossip connections
• Default value: true

consul_encrypt_verify_outgoing

• Verify outgoing Gossip connections
• Default value: true

consul_disable_keyring_file

• If set, the keyring will not be persisted to a file. Any installed keys will be lost on shutdown, and only the given -encrypt key will be available on startup.
• Default value: false

consul_raw_key

• Set the encryption key; should be the same across a cluster. If not present the key will be generated & retrieved from the bootstrapped server.
• Default value: ''

consul_tls_verify_incoming

• Verify incoming connections
  • Override with CONSUL_TLS_VERIFY_INCOMING environment variable
• Default value: false

consul_tls_verify_outgoing

• Verify outgoing connections
  • Override with CONSUL_TLS_VERIFY_OUTGOING environment variable
• Default value: true

consul_tls_verify_incoming_rpc

• Verify incoming connections on RPC endpoints (client certificates)
  • Override with CONSUL_TLS_VERIFY_INCOMING_RPC environment variable
• Default value: false

consul_tls_verify_incoming_https

• Verify incoming connections on HTTPS endpoints (client certificates)
  • Override with CONSUL_TLS_VERIFY_INCOMING_HTTPS environment variable
• Default value: false

consul_tls_verify_server_hostname

• Verify server hostname
  • Override with CONSUL_TLS_VERIFY_SERVER_HOSTNAME environment variable
• Default value: false

consul_tls_min_version

• Minimum acceptable TLS version
  • Can be overridden with CONSUL_TLS_MIN_VERSION environment variable
  • For versions < 1.12.0 use 'tls12,tls13,...'
• Default value: TLSv1_2

consul_tls_cipher_suites

• Comma-separated list of supported ciphersuites
• Default value: ""

consul_tls_prefer_server_cipher_suites

• Prefer server's cipher suite over client cipher suite
  • Can be overridden with CONSUL_TLS_PREFER_SERVER_CIPHER_SUITES environment variable
• Default value: false

auto_encrypt

• Auto encrypt
• Default value:

auto_encrypt:
  enabled: false

• Example:

auto_encrypt:
  enabled: true
  dns_san: ["consul.com"]
  ip_san: ["127.0.0.1"]

consul_force_install

• If true, then always install consul. Otherwise, consul will only be installed either if not present on the host, or if the installed version differs from consul_version.
• The role does not handle the orchestration of a rolling update of servers followed by client nodes
• Default value: false

consul_install_remotely

• Whether to download the files for installation directly on the remote hosts
• This is the only option on Windows as WinRM is somewhat limited in this scope
• Default value: false

consul_install_from_repo

• Boolean, whether to install consul from repository as opposed to installing the binary directly.
• Supported distros: Alma Linux, Amazon Linux, CentOS, Debian, Fedora, Ubuntu, Red Hat, Rocky.
• Default value: false

consul_ui

• Enable the consul ui?
• Default value: true

consul_ui_legacy

• Enable legacy consul ui mode
• Default value: false

consul_disable_update_check

• Disable the consul update check?
• Default value: false

consul_enable_script_checks

• Enable script based checks?
• Default value: false
• This is discouraged in favor of consul_enable_local_script_checks.

consul_enable_local_script_checks

• Enable locally defined script checks?
• Default value: false

consul_raft_protocol

• Raft protocol to use.
• Default value:
  • Consul versions <= 0.7.0: 1
  • Consul versions > 0.7.0: 3

consul_node_role

• The Consul role of the node, one of: bootstrap, server, or client
• Default value: client

One server should be designated as the bootstrap server, and the other servers will connect to this server. You can also specify client as the role, and Consul will be configured as a client agent instead of a server.

There are two methods to setup a cluster, the first one is to explicitly choose the bootstrap server, the other one is to let the servers elect a leader among themselves.

Here is an example of how the hosts inventory could be defined for a simple cluster of 3 servers, the first one being the designated bootstrap / leader:

[consul_instances]
consul1.consul consul_node_role=bootstrap
consul2.consul consul_node_role=server
consul3.consul consul_node_role=server
consul4.local consul_node_role=client

Or you can use the simpler method of letting them do their election process:

[consul_instances]
consul1.consul consul_node_role=server consul_bootstrap_expect=true
consul2.consul consul_node_role=server consul_bootstrap_expect=true
consul3.consul consul_node_role=server consul_bootstrap_expect=true
consul4.local consul_node_role=client

Note that this second form is the preferred one, because it is simpler.

consul_autopilot_enable

Autopilot is a set of new features added in Consul 0.8 to allow for automatic operator-friendly management of Consul servers. It includes cleanup of dead servers, monitoring the state of the Raft cluster, and stable server introduction.

https://www.consul.io/docs/guides/autopilot.html

• Enable Autopilot config (will be written to bootsrapper node)
  • Override with CONSUL_AUTOPILOT_ENABLE environment variable
• Default value: false

consul_autopilot_cleanup_dead_Servers

Dead servers will periodically be cleaned up and removed from the Raft peer set, to prevent them from interfering with the quorum size and leader elections. This cleanup will also happen whenever a new server is successfully added to the cluster.

• Enable Autopilot config (will be written to bootsrapper node)
  • Override with CONSUL_AUTOPILOT_CLEANUP_DEAD_SERVERS environment variable
• Default value: false

consul_autopilot_last_contact_threshold

Used in the serf health check to determine node health.

• Sets the threshold for time since last contact
  • Override with CONSUL_AUTOPILOT_LAST_CONTACT_THRESHOLD environment variable
• Default value: 200ms

consul_autopilot_max_trailing_logs

• Used in the serf health check to set a max-number of log entries nodes can trail the leader
  • Override with CONSUL_AUTOPILOT_MAX_TRAILING_LOGS environment variable
• Default value: 250

consul_autopilot_server_stabilization_time

• Time to allow a new node to stabilize
  • Override with CONSUL_AUTOPILOT_SERVER_STABILIZATION_TIME environment variable
• Default value: 10s

consul_autopilot_redundancy_zone_tag

Consul Enterprise Only (requires that CONSUL_ENTERPRISE is set to true)

• Override with CONSUL_AUTOPILOT_REDUNDANCY_ZONE_TAG environment variable
• Default value: az

consul_autopilot_disable_upgrade_migration

Consul Enterprise Only (requires that CONSUL_ENTERPRISE is set to true)

• Override with CONSUL_AUTOPILOT_DISABLE_UPGRADE_MIGRATION environment variable
• Default value: false

consul_autopilot_upgrade_version_tag

Consul Enterprise Only (requires that CONSUL_ENTERPRISE is set to true)

• Override with CONSUL_AUTOPILOT_UPGRADE_VERSION_TAG environment variable
• Default value: ''

consul_debug

• Enables the generation of additional config files in the Consul config directory for debug purpose
• Default value: false

consul_config_template_path

• If the default config template does not suit your needs, you can replace it with your own.
• Default value: templates/config.json.j2.

Custom Configuration Section

As Consul loads the configuration from files and directories in lexical order, typically merging on top of previously parsed configuration files, you may set custom configurations via consul_config_custom, which will be expanded into a file named config_z_custom.json within your consul_config_path which will be loaded after all other configuration by default.

An example usage for enabling telemetry:

  vars:
    consul_config_custom:
      telemetry:
        dogstatsd_addr: "localhost:8125"
        dogstatsd_tags:
          - "security"
          - "compliance"
        disable_hostname: true

Consul Snapshot Agent

Consul snapshot agent takes backup snaps on a set interval and stores them. Must have enterprise

consul_snapshot

• Bool, true will setup and start snapshot agent (enterprise only)
• Default value: false

consul_snapshot_storage

• Location snapshots will be stored. NOTE: path must end in snaps
• Default value: {{ consul_config_path }}/snaps

consul_snapshot_interval

• Default value: 1h

consul_snapshot_retain

OS and Distribution Variables

The consul binary works on most Linux platforms and is not distribution specific. However, some distributions require installation of specific OS packages with different package names.

consul_centos_pkg

• Consul package filename
• Default value: {{ consul_version }}_linux_amd64.zip

consul_centos_url

• Consul package download URL
• Default value: {{ consul_zip_url }}

consul_centos_sha256

• Consul download SHA256 summary
• Default value: SHA256 summary

consul_centos_os_packages

• List of OS packages to install
• Default value: list

consul_debian_pkg

• Consul package filename
• Default value: {{ consul_version }}_linux_amd64.zip

consul_debian_url

• Consul package download URL
• Default value: {{ consul_zip_url }}

consul_debian_sha256

• Consul download SHA256 summary
• Default value: SHA256 SUM

consul_debian_os_packages

• List of OS packages to install
• Default value: list

consul_redhat_pkg

• Consul package filename
• Default value: {{ consul_version }}_linux_amd64.zip

consul_redhat_url

• Consul package download URL
• Default value: {{ consul_zip_url }}

consul_redhat_sha256

• Consul download SHA256 summary
• Default value: SHA256 summary

consul_redhat_os_packages

• List of OS packages to install
• Default value: list

consul_systemd_restart_sec

• Integer value for systemd unit RestartSec option
• Default value: 42

consul_systemd_limit_nofile

• Integer value for systemd unit LimitNOFILE option
• Default value: 65536

consul_systemd_restart

• String value for systemd unit Restart option
• Default value: on-failure

consul_ubuntu_pkg

• Consul package filename
• Default value: {{ consul_version }}_linux_amd64.zip

consul_ubuntu_url

• Consul package download URL
• Default value: {{ consul_zip_url }}

consul_ubuntu_sha256

• Consul download SHA256 summary
• Default value: SHA256 summary

consul_ubuntu_os_packages

• List of OS packages to install
• Default value: list

consul_windows_pkg

• Consul package filename
• Default value: {{ consul_version }}_windows_amd64.zip

consul_windows_url

• Consul package download URL
• Default value: {{ consul_zip_url }}

consul_windows_sha256

• Consul download SHA256 summary
• Default value: SHA256 summary

consul_windows_os_packages

• List of OS packages to install
• Default value: list

consul_performance

• List of Consul performance tuning items
• Default value: list

raft_multiplier

• Raft multiplier scales key Raft timing parameters
• Default value: 1

leave_drain_time

• Node leave drain time is the dwell time for a server to honor requests while gracefully leaving

• Default value: 5s

rpc_hold_timeout

• RPC hold timeout is the duration that a client or server will retry internal RPC requests during leader elections
• Default value: 7s

leave_on_terminate

• leave_on_terminate If enabled, when the agent receives a TERM signal, it will send a Leave message to the rest of the cluster and gracefully leave. The default behavior for this feature varies based on whether or not the agent is running as a client or a server. On agents in client-mode, this defaults to true and for agents in server-mode, this defaults to false.

consul_limit

• Consul node limits (key-value)
• Supported in Consul version 0.9.3 or later
• Default value: {}
• Example:

consul_limits:
    http_max_conns_per_client: 250
    rpc_max_conns_per_client: 150

Dependencies

Ansible requires GNU tar and this role performs some local use of the unarchive module for efficiency, so ensure that your system has gtar and unzip installed and in the PATH. If you don't this role will install unzip on the remote machines to unarchive the ZIP files.

If you're on system with a different (i.e. BSD) tar, like macOS and you see odd errors during unarchive tasks, you could be missing gtar.

Installing Ansible on Windows requires the PowerShell Community Extensions. These already installed on Windows Server 2012 R2 and onward. If you're attempting this role on Windows Server 2008 or earlier, you'll want to install the extensions here.

Example Playbook

Basic installation is possible using the included site.yml playbook:

ansible-playbook -i hosts site.yml

You can also pass variables in using the --extra-vars option to the ansible-playbook command:

ansible-playbook -i hosts site.yml --extra-vars "consul_datacenter=maui"

Be aware that for clustering, the included site.yml does the following:

1. Executes consul role (installs Consul and bootstraps cluster)
2. Reconfigures bootstrap node to run without bootstrap-expect setting
3. Restarts bootstrap node

ACL Support

Basic support for ACLs is included in the role. You can set the environment variables CONSUL_ACL_ENABLE to true, and also set the CONSUL_ACL_DATACENTER environment variable to its correct value for your environment prior to executing your playbook; for example:

CONSUL_ACL_ENABLE=true CONSUL_ACL_DATACENTER=maui \
CONSUL_ACL_MASTER_TOKEN_DISPLAY=true ansible-playbook -i uat_hosts aloha.yml

If you want the automatically generated ACL Master Token value emitted to standard out during the play, set the environment variable CONSUL_ACL_MASTER_TOKEN_DISPLAY to true as in the above example.

If you want to use existing tokens, set the environment variables CONSUL_ACL_MASTER_TOKEN and CONSUL_ACL_REPLICATION_TOKEN as well, for example:

CONSUL_ACL_ENABLE=true CONSUL_ACL_DATACENTER=stjohn \
CONSUL_ACL_MASTER_TOKEN=0815C55B-3AD2-4C1B-BE9B-715CAAE3A4B2 \
CONSUL_ACL_REPLICATION_TOKEN=C609E56E-DD0B-4B99-A0AD-B079252354A0 \
CONSUL_ACL_MASTER_TOKEN_DISPLAY=true ansible-playbook -i uat_hosts sail.yml

There are a number of Ansible ACL variables you can override to further refine your initial ACL setup. They are not all currently picked up from environment variables, but do have some sensible defaults.

Check defaults/main.yml to see how some of he defaults (i.e. tokens) are automatically generated.

Dnsmasq DNS Forwarding Support

The role now includes support for DNS forwarding with Dnsmasq.

Enable like this:

ansible-playbook -i hosts site.yml --extra-vars "consul_dnsmasq_enable=true"

Then, you can query any of the agents via DNS directly via port 53, for example:

dig @consul1.consul consul3.node.consul

; <<>> DiG 9.8.3-P1 <<>> @consul1.consul consul3.node.consul
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29196
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;consul3.node.consul.   IN  A

;; ANSWER SECTION:
consul3.node.consul.  0 IN  A 10.1.42.230

;; Query time: 42 msec
;; SERVER: 10.1.42.210#53(10.1.42.210)
;; WHEN: Sun Aug  7 18:06:32 2016
;;

consul_delegate_datacenter_dns

• Whether to delegate Consul datacenter DNS domain to Consul
• Default value: false

consul_dnsmasq_enable

• Whether to install and configure DNS API forwarding on port 53 using DNSMasq
  • Override with CONSUL_DNSMASQ_ENABLE environment variable
• Default value: false

consul_dnsmasq_bind_interfaces

• Setting this option to true prevents DNSmasq from binding by default 0.0.0.0, but instead instructs it to bind to the specific network interfaces that correspond to the consul_dnsmasq_listen_addresses option
• Default value: false

consul_dnsmasq_consul_address

• Address used by DNSmasq to query consul
• Default value: consul_address.dns
• Defaults to 127.0.0.1 if consul's DNS is bound to all interfaces (eg 0.0.0.0)

consul_dnsmasq_cache

• dnsmasq cache-size
• If smaller then 0, the default dnsmasq setting will be used.
• Default value: -1

consul_dnsmasq_servers

• Upstream DNS servers used by dnsmasq
• Default value: 8.8.8.8 and 8.8.4.4

consul_dnsmasq_revservers

• Reverse lookup subnets
• Default value: []

consul_dnsmasq_no_poll

• Do not poll /etc/resolv.conf
• Default value: false

consul_dnsmasq_no_resolv

• Ignore /etc/resolv.conf file
• Default value: false

consul_dnsmasq_local_service

• Only allow requests from local subnets
• Default value: false

consul_dnsmasq_listen_addresses

• Custom list of addresses to listen on.
• Default value: []

consul_connect_enabled

• Enable Consul Connect feature
• Default value: false

consul_cleanup_ignore_files

• List of files to ignore during cleanup steps
• Default value: [{{ consul_configd_path }}/consul.env]

iptables DNS Forwarding Support

This role can also use iptables instead of Dnsmasq for forwarding DNS queries to Consul. You can enable it like this:

ansible-playbook -i hosts site.yml --extra-vars "consul_iptables_enable=true"

Note that iptables forwarding and DNSmasq forwarding cannot be used simultaneously and the execution of the role will stop with error if such a configuration is specified.

TLS Support

You can enable TLS encryption by dropping a CA certificate, server certificate, and server key into the role's files directory.

By default these are named:

• ca.crt (can be overridden by {{ consul_tls_ca_crt }})
• server.crt (can be overridden by {{ consul_tls_server_crt }})
• server.key (can be overridden by {{ consul_tls_server_key }})

Then either set the environment variable CONSUL_TLS_ENABLE=true or use the Ansible variable consul_tls_enable=true at role runtime.

Service management Support

You can create a configuration file for consul services. Add a list of service in the consul_services.

Services object:

Configuration example:

consul_services:
  - name: "openshift"
    tags: ['production']
  - name: "redis"
    id: "redis"
    tags: ['primary']
    address: ""
    meta:
      meta: "for my service"
    proxy:
      destination_service_name: "redis"
      destination_service_id: "redis1"
      local_service_address: "127.0.0.1"
      local_service_port: 9090
      config: {}
      upstreams:  []
    checks:
      - args: ["/home/consul/check.sh"]
        interval: "10s"

Then you can check that the service is well added to the catalog

> consul catalog services
consul
openshift
redis

Note: to delete a service that has been added from this role, remove it from the consul_services list and apply the role again.

Vagrant and VirtualBox

See examples/README_VAGRANT.md for details on quick Vagrant deployments under VirtualBox for development, evaluation, testing, etc.

License

BSD

Author Information

Brian Shumate

Contributors

Special thanks to the folks listed in CONTRIBUTORS.md for their contributions to this project.

Contributions are welcome, provided that you can agree to the terms outlined in CONTRIBUTING.md.