Out of Sync : Weblog

Out of Sync

Tuesday Oct 07, 2008

VMware Certifications for Sun x64 Rack Servers and Blades

If you want to know which x64 servers are certified with VMware, then this page is very useful:

http://www.sun.com/software/vmware/certification.jsp

For what it is worth!

Sun and Bull team up for 200 Teraflop HPC Cluster

Sun and Bull team up for 200 Teraflop HPC cluster named Juropa!

http://www.theregister.co.uk/2008/10/06/bull_german_super/

Those who have used our x64 line of servers know that they pack quite punch and their form factor belies the incredible performance delivered.  Now, that is unsurprising considering our Engg talent and expertise in the area of systems design.

Monday Sep 29, 2008

FAA upgrades its Air Traffic Systems to ZFS and Open Storage

The title says it all!  Hopefully, that would result in fewer delays!

FAA upgrades its Air Traffic Systems to ZFS and Open Storage.

Thursday Sep 25, 2008

Introduction to Optional Fencing

The fencing mechanism of SCX has been enhanced to make it optional.  Though it is recommended to use strong fencing mechanisms, some user environments require flexibility and in such cases, fencing can be turned off. 

Basics

* The fencing can be set a) globally or b) Individual disks. 

* Fencing type cannot be changed for disks configured as Quorum devices.

* Fencing type set at individual disk level will take precedence over global settings.

By default, the cluster will use Device ID (DID) pathcount  to determine the type of reservation protocol to be used.  For devices connected to 2 nodes, it will be PGR emulation and for 3 or greater connections, SCSI will be used.

How to determine what is the fencing type globally?

bash-3.00# scdidadm -G

The cluster is currently configured to use DID path count algorithm to determine fencing protocol for shared devices.

Now let us change the fencing type globally to nofencing:

bash-3.00# scdidadm -G nofencing
Warning: Device instance d1 is a quorum device - fencing protocol remains PATHCOUNT for the device.

Now to change the fencing algorithm to prefer scsi,

bash-3.00# scdidadm -G prefer3

** If scsi cannot be used for a subset of disks, the warning message will be displayed.

To return fencing to default settings,

bash-3.00# scdidadm -G pathcount

To change fencing at per disk level, use scdidadm with -F option:

To change the fencing type to noscrub,

bash-3.00# scdidadm -F nofencing-noscrub d2

** noscrub  switches fencing off without scrubbing the scsi keys. Keys are scrubbed only for scsi and not for PGRe.

For using global fencing settings,

bash-3.00# scdidadm -F useglobal d2

How to create a zone cluster?

The introduction of the new zone cluster functionality in the SCX 9/08 release opens the door to very creative use of available system resources.  To get started with it, I have created a simple cheat sheet.

Basics:

1.  Zone cluster uses a new zone of brand "cluster".  

2. For the cluster to work properly, you need to edit the /usr/lib/brand/cluster/config.xml file and add the following line:

    <privilege set="default" name="contract_identity" />

before the </brand>.  Make sure that you backup the file before editing it.

3. The clzonecluster (1CL) command creates the zone and configures it. 

4.  You need to have the encrypted password of the root user copied from the /etc/shadow file before starting the configuration along with the nameservice configuration.

5. Exclusive IP zones are not possible.

Steps:

*We'll use NIS for the deployment example.

bash-3.2# clzc configure zone-cluster
zone-cluster: No such zone cluster configured
Use 'create' to begin configuring a new zone cluster.
clzc:zone-cluster> create
clzc:zone-cluster> add capped-memory
clzc:zone-cluster:capped-memory> set physical=512M
clzc:zone-cluster:capped-memory> set swap=4g

clzc:zone-cluster:capped-memory> end

clzc:zone-cluster> set autoboot=true
clzc:zone-cluster> add sysid
clzc:zone-cluster:sysid> set root_password=***********
clzc:zone-cluster:sysid> set name_service="NIS{domain_name=sun.com name_server=nis(1.1.1.1)}"
clzc:zone-cluster:sysid> end
clzc:zone-cluster> add node
clzc:zone-cluster:node> set physical-host=<physical hostname of node you want to add>
clzc:zone-cluster:node> set hostname=<intended hostname of the zone on that node>
clzc:zone-cluster:node> add net
clzc:zone-cluster:node:net> set physical=bge0
clzc:zone-cluster:node:net> set address=<hostname/address of the zone>
clzc:zone-cluster:node:net> end
clzc:zone-cluster:node> end
clzc:zone-cluster> add node
clzc:zone-cluster:node> set physical-host=<hostname of the physical node>
clzc:zone-cluster:node> set hostname=<hostname for zone>
clzc:zone-cluster:node> add net
clzc:zone-cluster:node:net> set physical=bge0
clzc:zone-cluster:node:net> set address=<hostname/address of zone>
clzc:zone-cluster:node:net> end
clzc:zone-cluster:node> end
clzc:zone-cluster> set zonepath=/export/zonecluster
clzc:zone-cluster> verify
clzc:zone-cluster> exit

To verify, you can execute :

clzc verify <zone-cluster name>

To save the configuration for future use,

clzc export -f <file-name> <zone-cluster name>

To install the zone cluster,

clzc install <zone-cluster name>

To boot the zone cluster,

clzc boot <zone-cluster name>

To check the status of the zone cluster,

clzc status <name>

eg)

bash-3.00# clzc status

=== Zone Clusters ===

--- Zone Cluster Status ---

Name         Node Name   Zone HostName   Status   Zone Status
----         ---------   -------------   ------   -----------
virt-ker      ker2     vker2         Online   Running
                 ker1     vker1         Online   Running
                 ker3     vker3         Online   Running
                 ker4    vker4         Online   Running

**After the zone cluster boots for the first time, the clzc status command will take some time for it to show status as online since the configuration has to be done on the zone similar to a native zone.

To halt the zone cluster,

clzc halt <zone-cluster>

Ain't it cool? Hats off to our engineers for designing such a cool feature!

Happy virtual clustering!!