Hi to everyone!

I have Lenovo ix4-300d, with 2 disks x 4 TB with RAID1 (I have 2nd Lenovo ix4-300d, which does incremental backup from the first every night).

Recently one disk of these 2 x 4 TB has failed with Event 9121.

Since I had data backup from last night, I just bought 2 other 4TB disks and made an dd_rescue copy from both old to both new. Bad sectors was around 120 and nothing important was missing. I thought everything will be fine, but no - after starting with the new disks ix4 complains again that "Disk 2 failed and need to be replaced". I read almost every thread here, I managed to SSH, tried various suggestions. I found, that RAID1 was degraded and successfully rebuilded/synced it with mdadm tool.  State of both disks and both partitions (20GB system and 3.7 TB data) now is clean.

Since logs showed some strange future date "2029-12-04", I tried to clean the logs and audits (didn't deleted them, just moved them to "old" folder). Event log was emptied, I restarted the device but Event 9121 reappeared. Now that strange future date reappeared, but I think it's secondary and non-related problem.

I tried both offline check procedures - not helped. Unmounting /dev/mapper/577721d7_vg-****  and running e2fsck didn't help - no errors was shown.

I've got Case Number : CC9710, but not answered yet.

Question: Could someone guide me what to try next? Some kind of tool or script? I'm not a Linux guru, but I have years of experience and strong will to learn.

I don't want to move that 3-4 TB data to the old broken disks via local network just to try reinstalling - It will take days to move data back and forth. (Well, I will do it, but as last option.)