Out of Sync: Maddy's Blog

Zones as the choice of virtualization offers many benefits in Solaris Cluster by virtue of the many options available to suit every need.  But for some new users, it would be a tad confusing with all the options and which one to use for which situation.  I have tried to summarize my views in this blog on the best fit.

To start with, we'll list the options:

1. Failover Zone/ HA Zone

2. Zone node

3. Zone Cluster

How did we end up with so many solutions? The concept of zones is fairly new in Solaris, i.e, starting with Solaris 10.  As the feature matures, more features are added and accordingly the Sun Cluster product starts taking advantage of it.

Now, let us dive into the details!

FAILOVER ZONE/HA ZONE:

The first supported solution for zones on Solaris 10 with Sun Cluster was introduced with the Sun Cluster 3.1u4 release. It is a GDS agent that makes the zone failover from one cluster node to the other. Of course, it requires that the zone configuration on the nodes be identical and the zone be installed on the shared storage for enabling failover.  This solution also has an option of monitoring the applications running inside the zone using SMF. 

It also supports branded zones apart from native zone.  Solaris8, Solaris9 and lx branded zones can also be made HA. The SMF based monitoring is particularly useful for legacy applications that don't have a Sun Cluster agent but still requires HA. This solution has been used in the now famous "Flying Containers" presentations at various events!  GUUG-Frühjahrsfachgespräch 2008 Tutorium Teil 2: Flying Container (German). For over view on the technical implementation, refer to Sun Cluster and Solaris 10 Containers.

ZONE NODE:

The Sun Cluster 3.2 release, enabled zones to be treated like physical nodes to be part of RGs. On 3.2, cluster services are automatically started on any native zone installed and configured on a Sun Cluster node. For those applications that were supported on Solaris Containers, it provided HA out of the box! Hence it is best for those applications which are supported with containers and have a Sun Cluster agent but don't have the requirement of the zone itself failing over in case of a failure.

It is very helpful if you have the application running in a combination of physical nodes and zones. Also those applications which are scalable and have to hosted exclusively in zones.

ZONE CLUSTER:

The feature released in the latest Sun Cluster release SC 3.2u2, introduces a new brand of zone called "cluster".  It enables the administrator to create a set of identical "cluster" zones on various physical cluster nodes that form a virtual cluster.  The administrator can delegate devices and other resources to the Zone Cluster.

This solution is very useful in hosted environments.  A single physical cluster can be partitioned and many virtual clusters can  be created for hosting different applications/isolate the application and data. Refer to the blue print on Deploying Oracle RAC in Zone Clusters.

In summary, there are many options available in Sun Cluster for taking care of your application deployment in Solaris zones.  You can choose which is the best fit once you can understand the benefits of each and hopefully this article was helpful introduction!

When creating zones in OpenSolaris 05.08, setting capped-memory seem to prevent the zone from booting.

-bash-3.2# zoneadm -z sparse-zone boot
zoneadm: zone 'sparse-zone': enabling system/rcap service failed: entity not
found
zoneadm: zone 'sparse-zone': call to zoneadmd failed
-bash-3.2# zonecfg -z sparse-zone info
zonename: sparse-zone
zonepath: /export/sparse-zone
brand: ipkg
autoboot: false
bootargs:
pool:
limitpriv:
scheduling-class:
ip-type: shared
net:
        address: xxxxxx
        physical: e1000g0
        defrouter not specified
capped-memory:
        physical: 1G
        [swap: 4G]
rctl:
        name: zone.max-swap
        value: (priv=privileged,limit=4294967296,action=deny)
-bash-3.2# zonecfg -z sparse-zone verify
-bash-3.2# 

After a few futile attempts, I found that this setting requires SUNWrcap pkg which isn't available in the default installation and had to manually install the pkg from the repository. Then import and enable the manifest for it to work.

 -bash-3.2# svccfg import rcap.xml
-bash-3.2# svcs -a|grep rcap
disabled       10:23:59 svc:/system/rcap:default
-bash-3.2# svcadm enable svc:/system/rcap:default
-bash-3.2# svcs -a|grep rcap
online         10:24:28 svc:/system/rcap:default
-bash-3.2# !zo
zoneadm -z sparse-zone boot
zoneadm: zone 'sparse-zone': Unable to set route for interface lo0 to êþùþã
zoneadm: zone 'sparse-zone':
-bash-3.2#

Voila`!

Solaris Cluster Express 6/08 is now available for download!  You can
download the DVD image here.


What is new in this release?

*  This release runs on OpenSolaris Nevada build 86. The version of the
Sun Management Centre is now 3.1.

*  The HA agent for Solaris Containers is now enhanced to include
support for the Solaris 9 Branded Zones on SPARC platform. This
is very useful for those customers who still need to run some
applications on Solaris 9 while taking advantage of the new features of
Solaris 10 and above.


* The HA agent for PostgreSQL Database is now ehanced to support WAL
shipping.  This feature greatly enhances the deployment of PostgreSQL
database in Enterprise deployments.

* Support for Solaris Containers configured with exclusive IP is
included in this release.


* The SCX Geographic Edition is enhanced to support Oracle Data Guard
based replication.


* This release also contains the mandatory bug fixes and other minor
enhancements not mentioned above.

Stay tuned for more milestones along the open source journey!

Sun has agreed to purchase Innotek! If you were wondering  why Sun is acquiring yet another company with a different virtualization technology when it already offers a very comprehensive portfolio in the form of LDOMs, xVM & Containers, just take a look at the markets they address!  LDOMs is for our highly mutlithreaded, multicore Niagara line of processors, xVM for x86 based processors and Containers for OS based software virtualization!  VirtualBox is targeted at desktops and doesn't offer all the functionality of a server grade virtualization technology like LDOMs or xVM.

But what it does offer is a very wide range of OS support and some really cool features for developers! Just click on the link and check out all the things that might interest you.

And the icing on the cake - it is Free and Open! Now how about that for talking the talk and walking the walk?

I am surprised that the news didn't come out much earlier but better late than never.   Oracle is officially entering the VM market with its own implementation of Xen.  These days it is not possible to be in the OS market without having 2 things:  1. a decent virtualization  road map  2. a neat set to management tools to manage the increasingly multi-vendor DC. 

However, no vendor has the range of solutions that Sun does!  LDOMS, xVM & Zones - all built in and proven technologies without having to pay a ransom for support!