VA7410 operating in a secure mode

[Alexey Firsov]

Hello everyone,
I have va7410 with dual controllers configuration.
Now the battery of one of controllers is broken.
VA gives out the warnings:
"One or more of the batteries that maintain the controller NVRAM hardware is missing or has failed.
The array is operating in a secure mode with respect to NVRAM."
Productivity of disk operations has fallen.
How I can restore productivity before replacement of the battery?

Alex

[Torsten. · Accepted solution]

You cannot.

Because the battery has failed,, the array will no longer do chaching, but writes everything directly to the disks. That's why it is slower. Replace the battery and you will be fast again.

[Alexey Firsov]

Thank you for the answer, Torsten!

Battery of second controller is in normal state.
If I remove the controller with broken battery, this can help me resovle the problem with productivity?

Alex.

[TTr]

> If I remove the controller with broken battery...

Then all the I/O from this controller will be moved to the other controller. It may make the performance worse. You should replace the battery as soon as possible.

[Torsten.]

This is what happens on a healthy array:

Any **virtual** array must remember "where I wrote what". The array has this information in memory and will write it to the disk from time to time. You can adjust this behaviour called "Resiliency setting".

In case of power loss both controllers will keep this information in battery backed up memory, because without this information your data is really lost.

With your failed battery the array will

- disable write caching for data
- write every "where I wrote what" information directly to the disk

These are the 2 reasons why your array is slow now.

[Alexey Firsov]

Thanks for the answers!

I understand, that at failure of the battery the VA has ceased to use a cache to avoid losses of data in case of switching-off of a power. However falling of productivity leads to that I cannot make online backup my data, that can lead to even greater loss of data!
On some others disk arrays, for example IBM DS3200, I can say "use cache without battery" in my own risk.
On a VA7410 I cannot so to make?

[Torsten.]

Normally yes with Resiliency settings, but I don't know if you can change it with a *bad* battery on board.

[Eric Schrauth]

Thanks for your help.  Know this thread is old, but was wondering if you could help me with a question.  Can the battery be replaced while the system is live?  I have two controllers and one seems to be working fine.  How would I tell if the controllers are in a fail over mode?  running hp-ux 11.23 u