How to configure shared VMFS 1

[johnny99]

Hi

I have to setup two ESX 2.5 servers with a shared VMFS system.

The servers will have the ESX system on local disks and the VMFS system will be on our SAN.
Servers will each have 2 Emulex LP1050ex HBA's

Is there a special procedure to define the shared VMFS or will ESX do this automaticly?

Thanks

Johnny

 

[Chacalinc]

Take a look to the following pages:

http://www.vmware.com/support/esx25/doc/esx25admin_disks9.html#1015471

http://www.vmware.com/support/esx25/doc/esx25admin_cluster_setup_esx.html#999125

cheers.

 

[johnny99]

Thanks

I was not thinking about doing cluster of eg. Windows.
I have read that part of the manual, but that is not what I was thinking about.
What I was thinking about doing is not sharing disks on virtual machines, but "just" have two ESX servers to have all virtual machines on the shared VMFS so that I can load them on the server that has the lowest load.
I just want it very simple, like making a shutdown of a virtual server on one ESX server and then start it on the other one.

/johnny

 

[Chacalinc]

* Set the VMFS accessibility mode to public or shared.

Any VMFS volume on a disk that is on a SAN can have VMFS accessibility set to public or shared. Public, the default and generally recommended accessibility mode, makes the VMFS volume available to multiple physical servers. With VMFS-2 volumes, public access is concurrent to multiple physical servers, whereas for VMFS-1 volumes, public access is limited to a single server at a time. Shared VMFS volumes is required if you are using physical clusters without raw device mapping.

Be sure that only one ESX Server system has access to the SAN while you are using the VMware Management Interface to configure it by formatting the VMFS-2 volumes. After you have finished the configuration, be sure that all partitions on the shared disk are set for public or shared access for access by multiple ESX Servers.

Download:

http://www.vmware.com/pdf/esx25_san_cfg.pdf

Cheers.

 

[johnny99]

I have made the basic installation of the first ESX server
ESX installed on the local disks and I have defined a 150 GB VMFS-2 filesystem that I will share with the next ESX server that I hope to be able to install in 2 weeks.

When I read about public and shared I realy don't see the difference, except more risks on shared.
But is this what I need if I wanted to implement eg a shared windowsvolume for 2 virtual windows machines on two different ESX servers?

Do I have to do something special if I want to implement VMotion?

/johnny

 

[Chacalinc]

When I read about public and shared I realy don't see the difference, except more risks on shared.

You use public when the shared disk has VMFS in it, so both ESX can use the VMFS (one at a time in VMFS-1 and in concurrent in VMFS-2). In shared, you are using the LUN as [n]raw[/b], so is the virtualized server OS who is using the LUN, not the ESX, i.e. when you have a cluster between a virtual machine and another *physical* server.

But is this what I need if I wanted to implement eg a shared windowsvolume for 2 virtual windows machines on two different ESX servers?

If you want to share the LUNs with 2 ESX servers you need to have the LUNs as public and forated as VMFS-2 filesystems (for concurrent access).

Do I have to do something special if I want to implement VMotion?

No, you just need to share the LUNs as public and formated as VMFS-2. VMotion use this capability in order to get access to all resources and move a virtual machine from a ESX to another one.

 

[johnny99]

Thanks a lot.

/johnny