VM hosts as Serviceguard nodes

[Jozef_Novak]

Hello all,

I have a live environment with 2 rx2660 as VM hosts each running 3 guests. I am planning to implement a HA configuration with VM hosts as ServiceGuard nodes and the guests as packages. After going through VM admin guide, release notes and whitepapers, I am not sure about one thing. When setting up the guests as packages, do I need to re-create them on the alternate node ? Or is this done by the hpvmsg_package script ?

Basically I am trying to find out whether I need to create the guests, assign all devices and create the vswitches again on the other node after I configure the respective volume groups in shared mode and make them visible on the alternate nodes.

Thanks much,
Jozef

[Rita C Workman]

Hi Jozef,

I haven't gone into MC/SG on VM....yet.

But in one of the manuals, although it mentions that you can run this on the VM Host and on the VM Client it does make a distinctive statement:
=======================
11.1 Introduction to HP Serviceguard with Integrity VM
After you set up Integrity VM, you can install HP Serviceguard on either the VM Host or on the
HP-UX guest. Do not use Serviceguard on both the VM Host and the guest at the same time
======================

It seems to describe having the cluster within the nodes and they fail to one another. I found this in pdf HP T2767-90105 called HP Integrity Virtual Machines Installation, Configuration and Administration Version 3.50

Hope this helps,
Rita

[Rita C Workman]

...I meant to say

It seems to describe having the cluster within the VM Client/Guest nodes and they fail to one another.

/rcw

[Jozef_Novak]

Hello Rita,

thanks for your reply. Actually it is possible to run Serviceguard either on the VM host (in this case the entire virtual machine is configured as a package and is capable of failing over) or inside a VM in order to provide failover protection for the applications that the VM is running.

In my case, I am considering the first scenario (VMs as packages). What I am trying to find out is whether I have to recreate the VMs on the VMhost that will be acting as a failover node. (I already have a production environment with VMs running).

Regards,
Jozef

[melvyn burnard]

take a read of:
http://docs.hp.com/en/10560/DesigningHASolutions-SGandVM.pdf

It may help you

[Jozef_Novak]

Hello Melvyn,

yes I saw this one before. It is very good from conceptual point of view, but it did not explicitly say whether the VM that is to be packaged has to exist on both nodes first. However from the section below, I suppose that this is the case:

"It is highly recommended that the VM guest to be packaged should be started first on each VM host
node in the cluster to be sure that its backing stores are accessible from all cluster nodes."

If someone with experience with VMs and Serviceguard can confirm this, then it solves my question (Unfortunately I don't have any environment where I could test it first).

Thanks for your help.

[melvyn burnard]

Well even in a standard Serviceguiard build, you should ALWAYS set up the package on ALL nodes, and test it will start on each and every node (this includes networking set up etc.), so yes, you SHOULD do this before "packagizing" the VM.

[Jozef_Novak]

Okay, it's clear. Thank you for clarification and help.

[Jozef_Novak]

Question clarified.