mirror of https://github.com/Icinga/icinga2.git
490 lines
17 KiB
Markdown
490 lines
17 KiB
Markdown
## <a id="cluster"></a> Cluster
|
|
|
|
An Icinga 2 cluster consists of two or more nodes and can reside on multiple
|
|
architectures. The base concept of Icinga 2 is the possibility to add additional
|
|
features using components. In case of a cluster setup you have to add the
|
|
cluster feature to all nodes. Before you start configuring the diffent nodes
|
|
it's necessary to setup the underlying communication layer based on SSL.
|
|
|
|
### <a id="certificate-authority-certificates"></a> Certificate Authority and Certificates
|
|
|
|
Icinga 2 comes with two scripts helping you to create CA and node certificates
|
|
for you Icinga 2 Cluster.
|
|
|
|
The first step is the creation of CA using the following command:
|
|
|
|
icinga2-build-ca
|
|
|
|
Please make sure to export a variable containing an empty folder for the created
|
|
CA files:
|
|
|
|
export ICINGA_CA="/root/icinga-ca"
|
|
|
|
In the next step you have to create a certificate and a key file for every node
|
|
using the following command:
|
|
|
|
icinga2-build-key icinga-node-1
|
|
|
|
Please create a certificate and a key file for every node in the Icinga 2
|
|
Cluster and save the CA key in case you want to set up certificates for
|
|
additional nodes at a later date.
|
|
|
|
### <a id="enable-cluster-configuration"></a> Enable the Cluster Configuration
|
|
|
|
Until the cluster-component is moved into an independent feature you have to
|
|
enable the required libraries in the icinga2.conf configuration file:
|
|
|
|
library "cluster"
|
|
|
|
### <a id="configure-nodename"></a> Configure the Icinga Node Name
|
|
|
|
Instead of using the default FQDN as node name you can optionally set
|
|
that value using the [IcingaNodeName](#global-constants) constant.
|
|
This setting must be unique on each cluster node, and must also match
|
|
the name of the local [Endpoint](#objecttype-endpoint) object and the
|
|
SSL certificate common name.
|
|
|
|
const IcingaNodeName = "icinga-node-1"
|
|
|
|
Read further about additional [naming conventions](#cluster-naming-convention).
|
|
|
|
> **Note**
|
|
>
|
|
> Not specifying the node name will default to FQDN. Make sure that all
|
|
> configured endpoint names and set common names are in sync.
|
|
|
|
### <a id="configure-clusterlistener-object"></a> Configure the ClusterListener Object
|
|
|
|
The ClusterListener needs to be configured on every node in the cluster with the
|
|
following settings:
|
|
|
|
Configuration Setting |Value
|
|
-------------------------|------------------------------------
|
|
ca_path | path to ca.crt file
|
|
cert_path | path to server certificate
|
|
key_path | path to server key
|
|
bind_port | port for incoming and outgoing conns
|
|
peers | array of all reachable nodes
|
|
------------------------- ------------------------------------
|
|
|
|
A sample config part can look like this:
|
|
|
|
/**
|
|
* Load cluster library and configure ClusterListener using certificate files
|
|
*/
|
|
library "cluster"
|
|
|
|
object ClusterListener "cluster" {
|
|
ca_path = "/etc/icinga2/ca/ca.crt"
|
|
cert_path = "/etc/icinga2/ca/icinga-node-1.crt"
|
|
key_path = "/etc/icinga2/ca/icinga-node-1.key"
|
|
|
|
bind_port = 8888
|
|
|
|
peers = [ "icinga-node-2" ]
|
|
}
|
|
|
|
> **Note**
|
|
>
|
|
> The certificate files must be readable by the user Icinga 2 is running as. Also,
|
|
> the private key file should not be world-readable.
|
|
|
|
Peers configures the direction used to connect multiple nodes together. If have
|
|
a three node cluster consisting of
|
|
|
|
* node-1
|
|
* node-2
|
|
* node-3
|
|
|
|
and `node-3` is only reachable from `node-2`, you have to consider this in your
|
|
peer configuration.
|
|
|
|
### <a id="configure-cluster-endpoints"></a> Configure Cluster Endpoints
|
|
|
|
In addition to the configured port and hostname every endpoint can have specific
|
|
abilities to send configuration files to other nodes and limit the hosts allowed
|
|
to send configuration files.
|
|
|
|
Configuration Setting |Value
|
|
-------------------------|------------------------------------
|
|
host | hostname
|
|
port | port
|
|
accept_config | defines all nodes allowed to send configs
|
|
config_files | defines all files to be send to that node - MUST BE AN ABSOLUTE PATH
|
|
------------------------- ------------------------------------
|
|
|
|
A sample config part can look like this:
|
|
|
|
/**
|
|
* Configure config master endpoint
|
|
*/
|
|
|
|
object Endpoint "icinga-node-1" {
|
|
host = "icinga-node-1.localdomain"
|
|
port = 8888
|
|
config_files = ["/etc/icinga2/conf.d/*.conf"]
|
|
}
|
|
|
|
If you update the configuration files on the configured file sender, it will
|
|
force a restart on all receiving nodes after validating the new config.
|
|
|
|
A sample config part for a config receiver endpoint can look like this:
|
|
|
|
/**
|
|
* Configure config receiver endpoint
|
|
*/
|
|
|
|
object Endpoint "icinga-node-2" {
|
|
host = "icinga-node-2.localdomain"
|
|
port = 8888
|
|
accept_config = [ "icinga-node-1" ]
|
|
}
|
|
|
|
By default these configuration files are saved in /var/lib/icinga2/cluster/config.
|
|
|
|
In order to load configuration files which were received from a remote Icinga 2
|
|
instance you will have to add the following include directive to your
|
|
`icinga2.conf` configuration file:
|
|
|
|
include_recursive IcingaLocalStateDir + "/lib/icinga2/cluster/config"
|
|
|
|
### <a id="cluster-naming-convention"></a> Cluster Naming Convention
|
|
|
|
The SSL certificate common name (CN) will be used by the [ClusterListener](pbjecttype-clusterlistener)
|
|
object to determine the local authority. This name must match the local [Endpoint](#objecttype-endpoint)
|
|
object name.
|
|
|
|
Example:
|
|
|
|
# icinga2-build-key icinga-node-1
|
|
...
|
|
Common Name (e.g. server FQDN or YOUR name) [icinga-node-1]:
|
|
|
|
# vim cluster.conf
|
|
|
|
object Endpoint "icinga-node-1" {
|
|
host = "icinga-node-1.localdomain"
|
|
port = 8888
|
|
}
|
|
|
|
The [Endpoint](#objecttype-endpoint) name is further referenced as `peers` attribute on the
|
|
[ClusterListener](pbjecttype-clusterlistener) object.
|
|
|
|
object Endpoint "icinga-node-2" {
|
|
host = "icinga-node-2.localdomain"
|
|
port = 8888
|
|
}
|
|
|
|
object ClusterListener "cluster" {
|
|
ca_path = "/etc/icinga2/ca/ca.crt"
|
|
cert_path = "/etc/icinga2/ca/icinga-node-1.crt"
|
|
key_path = "/etc/icinga2/ca/icinga-node-1.key"
|
|
|
|
bind_port = 8888
|
|
|
|
peers = [ "icinga-node-2" ]
|
|
}
|
|
|
|
Specifying the local node name using the [IcingaNodeName](#global-constants) variable requires
|
|
the same name as used for the endpoint name and common name above. If not set, the FQDN is used.
|
|
|
|
const IcingaNodeName = "icinga-node-1"
|
|
|
|
|
|
### <a id="initial-cluster-sync"></a> Initial Cluster Sync
|
|
|
|
In order to make sure that all of your cluster nodes have the same state you will
|
|
have to pick one of the nodes as your initial "master" and copy its state file
|
|
to all the other nodes.
|
|
|
|
You can find the state file in `/var/lib/icinga2/icinga2.state`. Before copying
|
|
the state file you should make sure that all your cluster nodes are properly shut
|
|
down.
|
|
|
|
|
|
### <a id="assign-services-to-cluster-nodes"></a> Assign Services to Cluster Nodes
|
|
|
|
By default all services are distributed among the cluster nodes with the `Checker`
|
|
feature enabled.
|
|
If you require specific services to be only executed by one or more checker nodes
|
|
within the cluster, you must define `authorities` as additional service object
|
|
attribute. Required Endpoints must be defined as array.
|
|
|
|
apply Service "dmz-oracledb" {
|
|
import "generic-service"
|
|
|
|
authorities = [ "icinga-node-1" ]
|
|
|
|
assign where "oracle" in host.groups
|
|
}
|
|
|
|
> **Tip**
|
|
>
|
|
> Most common usecase is building a classic Master-Slave-Setup. The master node
|
|
> does not have the `Checker` feature enabled, and the slave nodes are checking
|
|
> services based on their location, inheriting from a global service template
|
|
> defining the authorities.
|
|
|
|
### <a id="cluster-health-check"></a> Cluster Health Check
|
|
|
|
The Icinga 2 [ITL](#itl) ships an internal check command checking all configured
|
|
`EndPoints` in the cluster setup. The check result will become critical if
|
|
one or more configured nodes are not connected.
|
|
|
|
Example:
|
|
|
|
apply Service "cluster" {
|
|
import "generic-service"
|
|
|
|
check_interval = 1m
|
|
check_command = "cluster"
|
|
authorities = [ "icinga2a" ]
|
|
|
|
assign where host.name = "icinga2a"
|
|
}
|
|
|
|
> **Note**
|
|
>
|
|
> Each cluster node should execute its own local cluster health check to
|
|
> get an idea about network related connection problems from different
|
|
> point of views. Use the `authorities` attribute to assign the service
|
|
> check to the configured node.
|
|
|
|
### <a id="host-multiple-cluster-nodes"></a> Host With Multiple Cluster Nodes
|
|
|
|
Special scenarios might require multiple cluster nodes running on a single host.
|
|
By default Icinga 2 and its features will drop their runtime data below the prefix
|
|
`IcingaLocalStateDir`. By default packages will set that path to `/var`.
|
|
You can either set that variable as constant configuration
|
|
definition in [icinga2.conf](#icinga2-conf) or pass it as runtime variable to
|
|
the Icinga 2 daemon.
|
|
|
|
# icinga2 -c /etc/icinga2/node1/icinga2.conf -DIcingaLocalStateDir=/opt/node1/var
|
|
|
|
|
|
### <a id="cluster-scenarios"></a> Cluster Scenarios
|
|
|
|
#### <a id="cluster-scenarios-features"></a> Features in Cluster
|
|
|
|
Each cluster instance may use available features. If you have multiple locations
|
|
or departments, they may write to their local database, or populate graphite.
|
|
Even further all commands are distributed (unless prohibited using [Domains](#domains)).
|
|
|
|
DB IDO on the left, graphite on the right side - works.
|
|
Icinga Web 2 on the left, checker and notifications on the right side - works too.
|
|
Everything on the left and on the right side - make sure to deal with duplicated notifications
|
|
and automated check distribution.
|
|
|
|
#### <a id="cluster-scenarios-location-based"></a> Location Based Cluster
|
|
|
|
That scenario fits if your instances are spread over the globe and they all report
|
|
to a central instance. Their network connection only works towards the central master
|
|
(or the master is able to connect, depending on firewall policies) which means
|
|
remote instances won't see each/connect to each other.
|
|
|
|
All events are synced to the central node, but the remote nodes can still run
|
|
local features such as a web interface, reporting, graphing, etc.
|
|
|
|
Imagine the following example with a central node in Nuremberg, and two remote DMZ
|
|
based instances in Berlin and Vienna. The configuration tree on the central instance
|
|
could look like this:
|
|
|
|
conf.d/
|
|
templates/
|
|
germany/
|
|
nuremberg/
|
|
hosts.conf
|
|
berlin/
|
|
hosts.conf
|
|
austria/
|
|
vienna/
|
|
hosts.conf
|
|
|
|
The configuration deployment should look like:
|
|
|
|
* The node `nuremberg` sends `conf.d/germany/berlin` to the `berlin` node.
|
|
* The node `nuremberg` sends `conf.d/austria/vienna` to the `vienna` node.
|
|
|
|
`conf.d/templates` is shared on all nodes.
|
|
|
|
The endpoint configuration on the `nuremberg` node would look like:
|
|
|
|
object Endpoint "nuremberg" {
|
|
host = "nuremberg.icinga.org"
|
|
port = 8888
|
|
}
|
|
|
|
object Endpoint "berlin" {
|
|
host = "berlin.icinga.org"
|
|
port = 8888
|
|
config_files_recursive = [ "/etc/icinga2/conf.d/templates",
|
|
"/etc/icinga2/conf.d/germany/berlin" ]
|
|
}
|
|
|
|
object Endpoint "vienna" {
|
|
host = "vienna.icinga.org"
|
|
port = 8888
|
|
config_files_recursive = [ "/etc/icinga2/conf.d/templates",
|
|
"/etc/icinga2/conf.d/austria/vienna" ]
|
|
}
|
|
|
|
Each remote node will only peer with the central `nuremberg` node. Therefore
|
|
only two endpoints are required for cluster connection. Furthermore the remote
|
|
node must include the received configuration by the cluster functionality.
|
|
|
|
Example for the configuration on the `berlin` node:
|
|
|
|
object Endpoint "nuremberg" {
|
|
host = "nuremberg.icinga.org"
|
|
port = 8888
|
|
}
|
|
|
|
object Endpoint "berlin" {
|
|
host = "berlin.icinga.org"
|
|
port = 8888
|
|
accept_config = [ "nuremberg" ]
|
|
}
|
|
|
|
include_recursive IcingaLocalStateDir + "/lib/icinga2/cluster/config"
|
|
|
|
Depenending on the network connectivity the connections can be either
|
|
established by the remote node or the central node.
|
|
|
|
Example for `berlin` node connecting to central `nuremberg` node:
|
|
|
|
library "cluster"
|
|
|
|
object ClusterListener "berlin-cluster" {
|
|
ca_path = "/etc/icinga2/ca/ca.crt"
|
|
cert_path = "/etc/icinga2/ca/berlin.crt"
|
|
key_path = "/etc/icinga2/ca/berlin.key"
|
|
bind_port = 8888
|
|
peers = [ "nuremberg" ]
|
|
}
|
|
|
|
Example for central `nuremberg` node connecting to remote nodes:
|
|
|
|
library "cluster"
|
|
|
|
object ClusterListener "nuremberg-cluster" {
|
|
ca_path = "/etc/icinga2/ca/ca.crt"
|
|
cert_path = "/etc/icinga2/ca/nuremberg.crt"
|
|
key_path = "/etc/icinga2/ca/nuremberg.key"
|
|
bind_port = 8888
|
|
peers = [ "berlin", "vienna" ]
|
|
}
|
|
|
|
The central node should not do any checks by itself. There's two possibilities to achieve
|
|
that:
|
|
|
|
* Disable the `checker` feature
|
|
* Pin the service object configuration to the remote endpoints using the [authorities](#assign-services-to-cluster-nodes)
|
|
attribute.
|
|
|
|
|
|
#### <a id="cluster-scenarios-load-distribution"></a> Load Distribution
|
|
|
|
If you are planning to off-load the checks to a defined set of remote workers
|
|
you can achieve that by:
|
|
|
|
* Deploying the configuration on all nodes.
|
|
* Let Icinga 2 distribute the load amongst all available nodes.
|
|
|
|
That way all remote check instances will receive the same configuration
|
|
but only execute their part. The central instance can also execute checks,
|
|
but you may also disable the `Checker` feature.
|
|
|
|
conf.d/
|
|
templates/
|
|
many/
|
|
|
|
If you are planning to have some checks executed by a specific set of checker nodes
|
|
just pin them using the [authorities](#assign-services-to-cluster-nodes) attribute.
|
|
|
|
Example on the `central` node:
|
|
|
|
object Endpoint "central" {
|
|
host = "central.icinga.org"
|
|
port = 8888
|
|
}
|
|
|
|
object Endpoint "checker1" {
|
|
host = "checker1.icinga.org"
|
|
port = 8888
|
|
config_files_recursive = [ "/etc/icinga2/conf.d" ]
|
|
}
|
|
|
|
object Endpoint "checker2" {
|
|
host = "checker2.icinga.org"
|
|
port = 8888
|
|
config_files_recursive = [ "/etc/icinga2/conf.d" ]
|
|
}
|
|
|
|
object ClusterListener "central-cluster" {
|
|
ca_path = "/etc/icinga2/ca/ca.crt"
|
|
cert_path = "/etc/icinga2/ca/central.crt"
|
|
key_path = "/etc/icinga2/ca/central.key"
|
|
bind_port = 8888
|
|
peers = [ "checker1", "checker2" ]
|
|
}
|
|
|
|
Example on `checker1` node:
|
|
|
|
object Endpoint "central" {
|
|
host = "central.icinga.org"
|
|
port = 8888
|
|
}
|
|
|
|
object Endpoint "checker1" {
|
|
host = "checker1.icinga.org"
|
|
port = 8888
|
|
accept_config = [ "central" ]
|
|
}
|
|
|
|
object Endpoint "checker2" {
|
|
host = "checker2.icinga.org"
|
|
port = 8888
|
|
accept_config = [ "central" ]
|
|
}
|
|
|
|
object ClusterListener "checker1-cluster" {
|
|
ca_path = "/etc/icinga2/ca/ca.crt"
|
|
cert_path = "/etc/icinga2/ca/checker1.crt"
|
|
key_path = "/etc/icinga2/ca/checker1.key"
|
|
bind_port = 8888
|
|
}
|
|
|
|
|
|
#### <a id="cluster-scenarios-high-availability"></a> High Availability
|
|
|
|
Two nodes in a high availability setup require an [initial cluster sync](#initial-cluster-sync).
|
|
Furthermore the active master node should deploy the configuration to the
|
|
second node, if that does not already happen by your provisioning tool. It primarly
|
|
depends which features are enabled/used. It is still required that some failover
|
|
mechanism detects for example which instance will be the notification "master".
|
|
|
|
|
|
#### <a id="cluster-scenarios-multiple-hierachies"></a> Multiple Hierachies
|
|
|
|
Your central instance collects all check results for reporting and graphing and also
|
|
does some sort of additional notifications.
|
|
The customers got their own instances in their local DMZs. They are limited to read/write
|
|
only their services, but replicate all events back to the central instance.
|
|
Within each DMZ there are additional check instances also serving interfaces for local
|
|
departments. The customers instances will collect all results, but also send them back to
|
|
your central instance.
|
|
Additionally the customers instance on the second level in the middle prohibits you from
|
|
sending commands to the down below department nodes. You're only allowed to receive the
|
|
results, and a subset of each customers configuration too.
|
|
|
|
Your central instance will generate global reports, aggregate alert notifications and check
|
|
additional dependencies (for example, the customers internet uplink and bandwidth usage).
|
|
|
|
The customers instance will only check a subset of local services and delegate the rest
|
|
to each department. Even though it acts as configuration master with a central dashboard
|
|
for all departments managing their configuration tree which is then deployed to all
|
|
department instances. Furthermore the central NOC is able to see what's going on.
|
|
|
|
The instances in the departments will serve a local interface, and allow the administrators
|
|
to reschedule checks or acknowledge problems for their services.
|