From: Zoran Kalenic (Zoran.Kalenic@lchclearnet.com)
Date: Tue Dec 14 2004 - 08:09:07 EST
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Thank you to Maria Gilliland who was the only person to respond to my query.
She has a similar set-up at her firm and provided the following advice.
1) LSM does provide a level of protection when importing disks to ensure disks are not imported to more than one host at a time, however, this can be overridden with a -C option.
2) Be very careful when assigning disks to two hosts and importing them as volumes are easily corrupted if they are imported onto two machines simultaneously.
My conclusion is that it is safest to leave the disks enabled on one machine at a time only. Instead of using the console to enable the disks, I now intend to use "hsxterm" and a script to reassign them to another host and to assist with the "fail over" process. Before reassigning, I will disable them on all hosts to ensure that they are never assigned to more than one host.
Regards,
Zoran Kalenic.
-----Original Message-----
Hi,
We currently have two Tru64 4.0F ES40 systems on two sites. One being the Production system and the other being the DR. Each site has an HSG80 with cross-site fibre links to each system.
Under normal conditions, the Production system has the SAN disks assigned and utilises LSM to mirror the disks on the local and remote SANs. This all works well.
When testing the DR site, we deport the disk group and re-assign them to the DR system. We then LSM import them onto the system and bring it up. This also works well.
During each step, the SAN configuration only enables one host to have access to the SAN storage at any one time. I would like to change this and permanently enable both systems to have access to the disks. This is to prevent the SAN being reconfigured each time we fail over.
My question is:
Is there a method in place to prevent the disks being imported onto both systems at the same time? Does LSM have this prevention built in? Can the SAN do it (such as the old SCSI reservation technique) through fibre connections?
I will provide a summary.
Regards,
Zoran Kalenic.
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