Hi Hujefa,
there is no formal way to learn about the uptime of a FlashSystem or the FCMs, respectively.
So, on one hand, my advise would be to schedule an FCM firmware update as soon as possible.
To be on the safe side, though, raise a ticket with support and upload a support package, so our team can have a look and can give you profound advise.
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Best regards,
Christian Schroeder
IBM Storage Virtualize Support with Passion
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