by Glynn Foster
svcbundle, and shows how developers and administrators can use it to integrate their applications with SMF more quickly.
Published October 2012
With the introduction of
svcbundle in Oracle Solaris 11.1, the creation of manifests and profiles is even easier, allowing you to take advantage of the benefits of automatic application restart without requiring you to have full knowledge of the XML file format that is used when integrating with the Service Management Facility (SMF).
SMF, first introduced in Oracle Solaris 10, is a feature of the operating system for managing system and application services, and it replaces the legacy
init scripting start-up mechanism common to prior releases of Oracle Solaris and other UNIX operating systems. SMF improves the availability of a system by ensuring that essential system and application services run continuously even in the event of any hardware or software failures. SMF is one of the components of the wider Oracle Solaris Predictive Self Healing capability.
This articles covers a new utility that was introduced in Oracle Solaris 11.1 called
svcbundle, and it shows how you can use this utility to integrate your applications with SMF more quickly. If you are unfamiliar with SMF, it is recommended you read " Introducing the Basics of Service Management Facility (SMF) on Oracle Solaris 11" and " Advanced Administration with the Service Management Facility (SMF) on Oracle Solaris 11" as prerequisite articles.
At the core of SMF is the concept of a service bundle, an XML-based file that is used to describe everything about a service or an instance of a service—including its configuration—prior to it being imported into the SMF configuration repository and used on a running system. Service bundles are used to deliver services into Oracle Solaris, but they also act as a useful way for you to deliver custom configuration across a variety of systems.
There are two types of service bundles used in SMF: manifests and profiles.
/lib/svc/manifestand they are automatically imported into the SMF configuration repository during system reboot, or they can be manually imported by restarting the
/etc/svc/profilesand applied during system reboot, or they can be applied again manually by restarting the
"How to Migrate Control of System Services from Scripts to the Service Management Facility" covers how SMF manifests can be written from scratch (or copied from an existing system manifest and modified) according to the XML DTD found in
/usr/share/lib/xml/dtd/service_bundle.dtd.1. In Oracle Solaris 11.1, however, the new easy-to-use
svcbundle command-line utility is available to help you create an SMF manifest or system profile without having knowledge of the XML file format.
svcbundle allows you to create and, optionally, install a manifest or system profile for common scenarios. As a result,
svcbundle makes a number of simple assumptions to deal with common scenarios:
svc:/milestone/multi-userservice ensures that the service is not started too early in the system boot process.
restartexec methods defaults to
You provide a series of name-value pairings to
svcbundle that are used to define different elements of a manifest or profile, for example, the service instance name; whether it should be enabled or disabled; different property values; start, stop, and refresh methods; and what type of service it should be. The utility can also help to facilitate the conversion of a legacy RC (run control) script to SMF.
As with many command-line utilities, it's easier to see by example, so we will show two uses of
svcbundleto Create an SMF Manifest
In this example, we will use
svcbundle to create an SMF manifest to automatically start Nagios upon reboot. Nagios is not currently packaged in the Oracle Solaris 11 package repository, so you must first download it from http://www.nagios.org and then preform a a simple installation.
In this example, we have installed Nagios into the
/usr/local/nagios prefix and modified the Apache Web server configuration file to be aware of the Nagios installation. We can start the Nagios daemon directly, as follows, using the
-d option and providing it the location of the configuration file:
# /usr/local/nagios/bin/nagios -d /usr/local/nagios/etc/nagios.cfg
We can now check that it's successfully running by navigating to
http://localhost/nagios in a browser, as shown in Figure 1:
Figure 1. Nagios
Once we have a working Nagios installation, the next step is to integrate this application into SMF so that it will start up during a system boot or restart if any software failure occurs. To do this, we will use
svcbundle to generate an SMF manifest for it, as follows:
# svcbundle -o nagios.xml -s service-name=application/nagios -s model=daemon \ -s start-method="/usr/local/nagios/bin/nagios -d /usr/local/nagios/etc/nagios.cfg"
In the example shown in Listing 1, we define three name-value pairs. We define the
-s service-name option as
application/nagios, which will result in the service being called
svc:/application/nagios:default. We define the
-s model option as
daemon so that SMF will track any processes for this service. We also define the
-s start-method option to be the same value that we used a little earlier to start the Nagios daemon. We will output this manifest to the file
nagios.xml, as defined by the
-o option. SMF will automatically validate the resulting manifest.
# cat nagios.xml <?xml version="1.0" ?> <!DOCTYPE service_bundle SYSTEM '/usr/share/lib/xml/dtd/service_bundle.dtd.1'> <!-- Manifest created by svcbundle (2012-Sep-11 00:19:49+1200) --> <service_bundle type="manifest" name="application/nagios"> <service version="1" type="service" name="application/nagios"> <!-- The following dependency keeps us from starting until the multi-user milestone is reached. --> <dependency restart_on="none" type="service" name="multi_user_dependency" grouping="require_all"> <service_fmri value="svc:/milestone/multi-user"/> </dependency> <exec_method timeout_seconds="60" type="method" name="start" exec="/usr/local/nagios/bin/nagios -d /usr/local/nagios/etc/nagios.cfg" /> <!-- The exec attribute below can be charged to a command that SMF should execute to stop the service. See smf_method(5) for more details. --> <exec_method timeout_seconds="60" type="method" name="stop" exec=":kill"/> <!-- The exec attribute below can be changed to a command that SMF should execute when the service is refreshed. Services are typically refreshed when their properties are changed in the SMF repository. See smf_method(5) for more details. It is common to retain the value of :true which means that SMF will take no action when the service is refreshed. Alternatively, you may wish to provide a method to reread the SMF repository and act on any configuration changes. --> <exec_method timeout_seconds="60" type="method" name="refresh" exec=":true"/> .... </service> </service_bundle>
Listing 1. Example Manifest
The next step is to take this manifest and install it into
/lib/svc/manifest/site by restarting the
svc:/system/manifest-import:default service. We will also restart the
svc:/network/http:apache22 service, since we have modified the Apache configuration.
# svcadm restart apache22 # cp nagios.xml /lib/svc/manifest/site # svcadm restart manifest-import # svcs nagios STATE STIME FMRI online 2:13:01 svc:/application/nagios:default # ps -ef | grep nagios nagios 25743 1 0 00:50:43 ? 0:06 /usr/local/nagios/bin/nagios -d /usr/local/nagios/etc/nagios.cfg
We could have also used the
-i option (instead of the
-o option) to install the generated SMF manifest directly into the system and automatically restart the
This is a simple example of how we can quickly generate a simple SMF manifest using
svcbundle. If you want to customize further, you can modify this template manifest once it has been generated.
svcbundleto Create an SMF System Profile
In this example, we will use
svcbundle to generate an SMF system profile to customize the name server address configuration in the
svc:/network/dns/client service. For this, we will need to use the
bundle-type name-value pairs, as follows:
# svcbundle -o nameserver-config.xml -s service-name=network/dns/client \ -s bundle-type=profile -s service-property="config:nameserver:net_address:192.168.0.1"
The default bundle type for
manifest, so we define
bundle-type to be
profile. Service and service instance configuration properties are defined using a quadruple separated by colons: property group, property name, property type, and value. In Listing 2, we define the
service-property name value to be
# cat nameserver-config.xml <?xml version="1.0" ?> <!DOCTYPE service_bundle SYSTEM '/usr/share/lib/xml/dtd/service_bundle.dtd.1'> <!-- Manifest created by svcbundle (2012-Sep-11 02:33:16+1200) --> <service_bundle type="profile" name="network/dns/client"> <service version="1" type="service" name="network/dns/client"> <property_group type="application" name="config"> <propval type="net_address" name="nameserver" value="192.168.0.1"/> </property_group> </service> </service_bundle>
Listing 2. Example Profile
As before with the SMF manifest, we now need to take this SMF system configuration profile and install it onto the system. We achieve this by copying it to
/etc/svc/profile/site/ and restarting the
# cp nameserver-config.xml /etc/svc/profile/site # svcadm restart manifest-import # svcprop -p config/nameserver dns/client 192.168.0.1
As before, we could have used the
-i option to directly install the profile onto the system.
This is a simple example just setting one property of a service. At this time,
svcbundle supports creating a system configuration profile for only a single service or service instance, but more-complicated profiles can be constructed once these initial profiles have been created.
If you are managing system services and applications on Oracle Solaris 11, SMF provides a number of benefits including automatic service restart, consolidated service configuration, and integration into the fault management framework. A new tool,
svcbundle, can help you to create SMF manifests and integrate critical services and applications into the SMF framework. It can also be used to create system profiles to provide customization across Oracle Solaris systems installed in the data center environment.
Glynn Foster is a Principal Product Manager for Oracle Solaris and works on technology areas that include the Image Packaging System (IPS) and Service Management Facility (SMF). Glynn joined Oracle in 2010 as part of the Sun Microsystems acquisition.
|Revision 1.0, 10/22/2012|