All LUNS are disappear after reboot

[Dhananjaya Amarakoon]

We have EVA4100 at customer side and they  used it as backup EVA.  On that EVA following parts has already failed.   Cache battery of both controllers and two controllers blow in one controller.  For maintenance   purpose we had to power down the SAN setup. After power up the SAN setup there is no any vdisk visible in host end.  There are 5 hosts and there is no any HDD visible in any server.
But I have test EVA path test and it is successful from CVE.
What can be the reason for this issue ?  is that both cache battery failure ?

Best Regards
Dhananjaya

[Johan Guldmyr]

Yes, without working cache batteries the EVA does not present the LUNs to the hosts.

[Dhananjaya Amarakoon]

Thanks Johan, is that happened after reboot while cache battery failed or as soon as both cache batteries failed ? Because it worked even both cache batteries already failed conditions ?

Dhananjaya

[Johan Guldmyr]

It depends on the definition of 'failed'. Is that as seen from CV? On leds? Or in the Controller Event Log?
It may be that the batteries failed during the POST (where batteries are tested).
Batteries are also tested periodically on the EVAs but there are some bugs in the testing algorithm in some firmwares. I believe they've been improved in the 6.220 and 6.240.

[Dhananjaya Amarakoon]

Hi Johan,
Both batteries attention mark led's are lit with amber color. On that occasion LUNs were there in host end before power down the EVA. but after power up there were not LUNs in host end. Unfortunately we don't have cache batteries to replace. Is there any other option we can do to make this luns visible to host side.

[Johan Guldmyr]

I think you'll eventually find that you need to replace the batteries.

When a battery has failed you really shouldn't be trying to use it.

However, I guess you could try reseating the batteries, restarting the controllers, power cycling the EVA, upgrade firmware.

When you're handling the failed batteries, be careful as they may have leaked. Also do check inside the controllers on the connectors, if there's corrosion/miscoloring there you'll have to replace the controller too.

[Dhananjaya Amarakoon]

thanks

Other than firmware upgrade I did everything. One moment I did controller re sysnc as well. that time controller came to fault state. So that time I power down eva and started again. that time controller back to work. I noted one thing while resync, From the host end it identified presented luns from device manger under disk drive ( not in the disk management ) . but after controller restart again it disappear.