Virtual Solaris machines at IoA Cambridge

We have five virtual machines running Solaris at IoA Cambridge. Three are currently allocated for testing the AstroGrid components during the transition to VOResource 1.0. Two others support the production community and VOSpace for Cambridge. We have capacity to run a sixth machine if needed.

Solaris zones

Solaris comes with its own virtualization system inspired by mainframe practice. Each VM runs the same, Solaris kernel as the host (no "guest" OS) and resource allocations to the VMs can be controlled very precisely. The overhead of virtualization is claimed (by SUN) to be lower than systems such as VMware and Xen.

A virtual machine in Solaris is known as a zone. System resources are allocated to pools and the combination of some pools and zones is known as a container. A zone can only use the resources in the pool allocated to its container. Each container has only one pool but may have more than one zone; in that case, the zones compete for the resources in the pool.

The global zone is the base machine: the host in VMWare terms.

Each zone, including the global one, has its own IP address.

The IoA machines and their zones

The machines recently installed in Cambridge are two SUN 2200 servers. They each have two dual-core, Opteron processors; the zone system sees these as four, independent CPUs. The physical machines have 4GB of RAM each and 250GB of disc.

The base machines are:

• casx019.ast.cam.ac.uk
• casx020.ast.cam.ac.uk

For simplicity, each host has been given three zones (apart from the global one) and each non-global zone has been given exclusive use of one processor core. This leaves two cores for the global zone on each host, of which one might later be used to make an extra zone. Each non-global zone has been given a memory limit of 1G physical and 2GB swap. Disc space is shared between the zones without constraints.

The zones are:

• casx019-zone1.ast.cam.ac.uk
• casx019-zone2.ast.cam.ac.uk
• casx019-zone3.ast.cam.ac.uk
• casx020-zone1.ast.cam.ac.uk
• casx020-zone2.ast.cam.ac.uk

Please edit this page to allocate a zone to your component.

Only these non-global zones are to be used for the AstroGrid work. We shall not be running any AstroGrid services in the global zones.

The accounts and directories

The zones have only local accounts; they do not support the cluster-wide accounts of normal Cambridge users. An account in one zone is totally separate from an account of the same name in another zone or host.

Development machines

For AstroGrid testing, there is only one account: reggie, an unprivileged account. It's the same username and UID on all the zones, but the accounts are separate as noted above. If you are in the team assigned at the December consortium meeting then jabber me to get the password.

reggie has home space at /home/reggie and read-write access to the directory /astrogrid. The intention is that the service installations be put into /astrogrid and tools and test materials stay in /home/reggie. For any given zone, /home/reggie and /astrogrid are on the same disc partition. For any given host, all the directories of all its zones are drawing from a pool of ~200GB of storage local to the physical machine.

The reggie accounts should have access to the "normal" tools and utilities of a Solaris machine at IoA Cambridge. I have not added any AstroGrid parts such as extra JDKs or Tomcats.

Production machines

The production machines use only the root account. This cannot be directly accessed by ssh. Instead, it is necesary to ssh to the global zone and then use the zlogin command, e.g. zlogin zone1.

On the production machines, /astrogrid is present but /home/reggie is not. All the materials for AstroGrid services are in /astrogrid except for a few service-administration files which are in operating-system directories.

Allocation of zones to AstroGrid components and developers

Test machines

• casx019-zone1: Registry, KevinBenson
• casx020-zone1: Community, GuyRixon
• casx020-zone2: MySpace^?, DaveMorris

Production machines

• casx019-zone2: Community
• casx019-zone3: VOSpace

Machines not yet allocated

• casx020-zone3 (zone is not installed yet, but the IP address has been allocated)

Support

If something is broken or bizarre in the OS of the zones, please report it to me rather than directly to the sysadmins in Cambridge.

-- GuyRixon - 18 Dec 2007