# Differences between Icinga 1.x and 2 ## Configuration Format Icinga 1.x supports two configuration formats: key-value-based settings in the `icinga.cfg` cofiguration file and object-based in included files (`cfg_dir`, `cfg_file`). The path to the `icinga.cfg` configuration file must be passed to the Icinga daemon at startup. enable_notifications=1 define service { notifications_enabled=0 } Icinga 2 supports objects and (global) variables, but does not make a difference if it's the main configuration file, or any included file. set IcingaEnableNotifications = 1, object Service "test" { enable_notifications = 0, } ### Sample Configuration and ITL While Icinga 1.x ships sample configuration and templates spread in various object files Icinga 2 moves all templates into the Icinga Template Library (ITL) and includes that in the sample configuration. The ITL will be updated on every releases and should not be edited by the user. > **Note** > > Sample configuration files are located in the `conf.d/` directory which is > included in `icinga2.conf` by default. ### Include Files and Directories In Icinga 1.x the `icinga.cfg` file contains `cfg_file` and `cfg_dir` directives. The `cfg_dir` directive recursively includes all files with a `.cfg` suffix in the given directory. Only absolute paths may be used. The `cfg_file` and `cfg_dir` directives can include the same file twice which leads to configuration errors in Icinga 1.x. cfg_file=/etc/icinga/objects/commands.cfg cfg_dir=/etc/icinga/objects Icinga 2 supports wildcard includes and relative paths, e.g. for including `conf.d/*.conf` in the same directory. A global search path for includes is available for advanced features like the Icinga Template Library (ITL). The file suffix does not matter as long as it matches the (wildcard) include expression. include "conf.d/*.conf" include > **Best Practice** > > By convention the `.conf` suffix is used for Icinga 2 configuration files. ## Resource File and Global Macros Global macros such as for the plugin directory, usernames and passwords can be set in the `resource.cfg` configuration file in Icinga 1.x. By convention the `USER1` macro is used to define the directory for the plugins. Icinga 2 uses a global `IcingaMacros` variable which is set in the `conf.d/macros.conf` file: /** * Global macros */ set IcingaMacros = { plugindir = "/usr/lib/nagios/plugins" } ## Comments In Icinga 1.x comments are made using a leading hash (`#`) or a semi-colon (`;`) for inline comments. In Icinga 2 comments can either be encapsulated by `/*` and `*/` (allowing for multi-line comments) or starting with two slashes (`//`). ## Object names Object names must not contain a colon (`:`). Use the `display_name` attribute to specify user-friendly names which should be shown in UIs (supported by Icinga 1.x Classic UI and Web). Object names are not specified using attributes (e.g. `service_description` for hosts) like in Icinga 1.x but directly after their type definition. define service { host_name localhost service_description ping4 } object Service "localhost-ping4" { } ## Templates In Icinga 1.x templates are identified using `register 0`. Icinga 2 uses the `template` identifier. template Service "ping4-template" { } Icinga 1.x objects inherit from templates using the `use` attribute. Icinga 2 uses the keyword `inherits` after the object name and requires a comma-separated list with template names in double quotes. define service { service_description testservice use tmpl1,tmpl2,tmpl3 } object Service "testservice" inherits "tmpl1", "tmpl2", "tmpl3" { } ## Object attributes Icinga 1.x separates attribute and value with whitespaces/tabs. Icinga 2 requires an equal sign (=) between them. define service { check_interval 5 } object Service "test" { check_interval = 5m, } > **Note** > > Please note that the default time value is seconds, if no duration literal > is given. check_interval = 5 behaves the same as check_interval = 5s. All strings require double quotes in Icinga 2. Therefore a double-quote must be escaped with a backslash (e.g. in command line). If an attribute identifier starts with a number, it must be encapsulated with double quotes as well. Unlike in Icinga 1.x all attributes within the current object must be terminated with a comma (,). ## Host Service Relation In Icinga 1.x a service object is associated with a host by defining the `host_name` attribute in the service definition. Alternate object tricks refer to `hostgroup_name` or behavior changing regular expression. It's not possible to define a service definition within a host definition. The preferred way of associating hosts with services in Icinga 2 are services defined inline to the host object (or template) definition. Icinga 2 will implicitely create a new service object on configuration activation. These inline service definitions can reference service templates. Linking a service to a host is still possible with the 'host' attribute in a service object in Icinga 2. ### Service Hostgroup to Hosts Trick A common pattern in Icinga 1.x is to add services to hostgroups. When a host is added as hostgroup member, it will automatically collect all services linked to that hostgroup. Inheriting services from a parent hostgroup to a member hostgroup does not work. define hostgroup { hostgroup_name testhg } define service { service_description testservice hostgroup_name testhg } define host { host_name testhost hostgroups testhg } Since it's possible to define services inline in a host template object and inherit them to actual host objects in Icinga 2 the preferred method works like: Create a host template (acting as "hostgroup" relation) and define all services (either inline, or reference a service template). Then let all hosts inherit from that host template, collecting all service relations. template Host "testhg" { services["testservice"] = { ... } } object Host "testhost" inherits "testhg" { ... } Hostgroups in Icinga 2 are only used for grouping the views but must not be used for host service relation building. > **Note** > > It's also possible to modify attributes in the host's service array inherited > from the host template. E.g. macros. ## Users Contacts have been renamed to Users (same for groups). A user does not only provide attributes and macros used for notifications, but is also used for authorization checks. In Icinga 2 notification commands are not directly associated with users. Instead the notification command is specified in `Notification` objects. The `StatusDataWriter`, `IdoMySqlConnection` and `LivestatusListener` types will provide the contact and contactgroups attributes for services for compatibility reasons. These values are calculated from all services, their notifications, and their users. ## Macros ### Command Macros If you have previously used Icinga 1.x you may already be familiar with user and argument macros (e.g., `USER1` or `ARG1`). Unlike in Icinga 1.x macros may have arbitrary names and arguments are no longer specified in the `check_command` setting. In Icinga 1.x argument macros are specified in the `check_command` attribute and are separated from the command name using an exclamation mark (`!`). define command { command_name ping4 command_line $USER1$/check_ping -H $HOSTADDRESS$ -w $ARG1$ -c $ARG2$ -p 5 } define service{ use local-service host_name localhost service_description PING check_command check_ping!100.0,20%!500.0,60% } In Icinga 2 ### Environment Macros The global configuration setting `enable_environment_macros` does not exist in Icinga 2. Macros exported into the environment must be set using the `export_macros` attribute in command objects. ## Checks ### Host Check Unlike in Icinga 1.x hosts are not checkable objects in Icinga 2. Instead hosts inherit their state from the service that is specified using the `check` attribute. ### Check Output Icinga 2 does not make a difference between `output` (first line) and `long_output` (remaining lines) like in Icinga 1.x. Performance Data is provided separately. The `StatusDataWriter`, `IdoMysqlConnection` and `LivestatusListener` types split the raw output into `output` (first line) and `long_output` (remaining lines) for compatibility reasons. ### Initial State Icinga 1.x uses the `max_service_check_spread` setting to specify a timerange where the initial state checks must have happened. Icinga 2 will use the `retry_interval` setting instead and `check_interval` divided by 5 if `retry_interval` is not defined. ### Performance Data There is no host performance data generated in Icinga 2 because there are no real host checks anymore. Therefore the PerfDataWriter will only write service performance data files. ## Commands Unlike in Icinga 1.x there are 3 different command types in Icinga 2: `CheckCommand`, `NotificationCommand` and EventCommand`. For example in Icinga 1.x it is possible to accidently use a notification command as an event handler which might cause problems depending on which macros are used in the notification command. In Icinga 2 these command types are separated and will generate an error on configuration validation if used in the wrong context. While Icinga 2 still supports the complete command line in command objects, it's also possible to encapsulate all arguments into double quotes and passing them as array to the `command_line` attribute i.e. for better readability. It's also possible to define default (argument) macros for the command itself which can be overridden by a service (argument) macro. ## Groups ### Group Membership Assigning members to hostgroups, servicegroups, usergroups is done only at the host/service/user object using the 'groups' attribute. The old method defining that directly as group attribute is not supported. Better use templates inheriting the 'groups' attribute to all your objects. ### Hostgroup with Services Hostgroups are used for grouping only, and cannot be used for object tricks like in Icinga 1.x. ## Notifications Notifications are a new object type in Icinga 2. Imagine the following notification configuration problem in Icinga 1.x: * Service A should notify contact X via SMS * Service B should notify contact X via Mail * Service C should notify contact Y via Mail and SMS * Contact X and Y should also be used for authorization (e.g. in Classic UI) The only way achieving a semi-clean solution is to * Create contact X-sms, set service_notification_command for sms, assign contact to service A * Create contact X-mail, set service_notification_command for mail, assign contact to service B * Create contact Y, set service_notification_command for sms and mail, assign contact to service C * Create contact X without notification commands, assign to service A and B Basically you are required to create duplicated contacts for either each notification method or used for authorization only. Icinga 2 attempts to solve that problem in this way * Create user X, set SMS and Mail attributes, used for authorization * Create user Y, set SMS and Mail attributes, used for authorization * Create notification A-SMS, set notification_command for sms, add user X, assign notification A-SMS to service A * Create notification B-Mail, set notification_command for mail, add user X, assign notification Mail to service B * Create notification C-SMS, set notification_command for sms, add user Y, assign notification C-SMS to service C * Create notification C-Mail, set notification_command for mail, add user Y, assign notification C-Mail to service C > **Note** > > Notification objects are not required to be service-agnostic. They may use > global notification templates and can be added to a service wherever needed. Previously in Icinga 1.x it looked like this: service -> (contact, contactgroup) -> notification command In Icinga 2 it will look like this: Service -> Notification -> NotificationCommand -> User, UserGroup ### Escalations Escalations in Icinga 1.x require a separated object matching on existing objects. Escalations happen between a defined start and end time which is calculated from the notification_interval: start = notification start + (notification_interval * first_notification) end = notification start + (notification_interval * last_notification) In theory first_notification and last_notification can be set to readable numbers. In practice users are manipulating those attributes in combination with notification_interval in order to get a start and end time. In Icinga 2 the notification object can be used as notification escalation if the start and end times are defined within the 'times' attribute using duration literals (e.g. 30m). The Icinga 2 escalation does not replace the current running notification. In Icinga 1.x it's required to copy the contacts from the service notification to the escalation to garantuee the normal notifications once an escalation happens. That's not necessary with Icinga 2 only requiring an additional notification object for the escalation itself. ### Notification Options Unlike Icinga 1.x with the 'notification_options' attribute with comma-separated state and type filters, Icinga 2 uses two configuration attributes for that. All state and type filter use long names or'd with a pipe together notification_options w,u,c,r,f,s notification_state_filter = (StateFilterWarning | StateFilterUnknown | StateFilterCritical), notification_type_filter = (NotificationProblem | NotificationRecovery | NotificationFlappingStart | NotificationFlappingEnd | NotificationDowntimeStart | NotificationDowntimeEnd | NotificationDowntimeRemoved) > **Note** > > Please note that `NotificationProblem` as type is required for all problem > notifications. Icinga 2 adds more fine-grained type filters for acknowledgements, downtime and flapping type (start, end, ...). > **Note** > > Notification state and type filters are only valid configuration attributes for > Notification and User objects. ## Dependencies and Parents In Icinga 1.x it's possible to define host parents to determine network reachability and keep a host's state unreachable rather than down. Furthermore there are host and service dependencies preventing unnecessary checks and notifications. A host must not depend on a service, and vice versa. All dependencies are configured as separate objects and cannot be set directly on the host or service object. Icinga 2 adds host and service dependencies as attribute directly onto the host or service object or template. A service can now depend on a host, and vice versa. A service has an implicit dependeny (parent) to its host. A host to host dependency acts implicit as host parent relation. StatusDataWriter, IdoMysqlConnection and LivestatusListener support the Icinga 1.x schema with dependencies and parent attributes for compatibility reasons. ## Flapping The Icinga 1.x flapping detection uses the last 21 states of a service. This value is hardcoded and cannot be changed. The algorithm on determining a flapping state is flap threshold = (number of actual state changes / number of possible state changes) * 100% comparing that to low and high flapping thresholds. The algorithm uses in Icinga 2 does not store the past states but calculcates the flapping threshold from a single value based on counters and half-life values. Icinga 2 compares the value with a single flapping threshold configuration attribute. ## State Retention Icinga 1.x uses retention.dat to save historical and modified-at-runtime data over restarts. Icinga 2 uses its own icinga2.state file with a json-like serialized format. ## Logging Icinga 1.x supports syslog facilities and writes to its own icinga.log and archives. These logs are used in Icinga 1.x Classic UI to generate historical reports. Icinga 2 compat library provides the CompatLogger object which writes the icinga.log and archive in Icinga 1.x format in order to stay compatible with Classic UI and other addons. The native Icinga 2 logging facilities are split into three configuration objects: SyslogLogger, FileLogger, StreamLogger. Each of them got their own severity and target configuration. ## Broker Modules and Features Icinga 1.x broker modules are binary incompatible with the Icinga 2 component loader. Therefore the module configuration cannot be copied 1:1 Icinga 1.x IDOUtils was implemented from scratch as Icinga 2 feature which can be loaded and enabled on-demand. The Icinga 1.x Livestatus addon is implemented as Icinga 2 LivestatusListener. Icinga 1.x broker modules used for check distributions are replaced by the Icinga 2 cluster and distributed capabilities using the same protocol and security mechanisms as the Icinga 2 instance itself. Each feature can be created multiple times, i.e. having 3 IDO Mysql databases, 5 Performance Data Writers and 2 Livestatus Listeners (one listening on tcp, and one on unix sockets). ### IDOUtils Database Backend Icinga 2 uses IdoConnection configuration objects re-using some options known from Icinga 1.x IDOUtils such as the database credentials, instance_name or the cleanup attributes for max age of table entries. ### Enable Features Icinga 2 features require a library to be loaded, and object configuration. In order to simplify the process of enabling/disabling these features Icinga 2 ships with two scripts inspired by Apache: `i2enfeature` and `i2disfeature`.