VNX Symptom Code : 802 - data mover panic rwInode: write bad inode (Dell EMC Correctable)

None: Data mover panic during normal operations.

A data mover panic has happened and after the data mover has failed over to the standby or rebooted in the case of no standby avaiable, one file system will be unmounted and marked as corrupt.

Brief Description: Slot X has panicked - post panic logging complete: rwInode: write bad inode. Dump information can be found in 
/nas/log/post_panic_info_date_time_slot_x.log.


DART panic/fault message: 

    rwInode: write bad inode

Panicking Processor: 2
DART stack trace:
   0x3a7d310: 0x13dba4 handle_panic+0xb
   0x4162b000: 0x8465ed _ZN8inoCache7rwInodeEjP6dinodeiP11UFS_LogHold+
   0x4162b050: 0x866d7e _ZN9UFS_Vnode16finishInodeWriteEPvS0_+0x212
   0x4162b090: 0x930a52 _ZN20UFS_UpdateDescriptor8completeE11File_Stat
   0x4162b200: 0x877315 _ZN9UFS_Vnode9setLengthEyiiiP13Buffer_Cached+0
   0x4162b280: 0x1401a37 _ZN10DHSM_Vnode9setLengthEyiiiP13Buffer_Cache
   0x4162b320: 0x79781f _ZN9File_Fork8truncateEyR14lockCredentialPK11s
   0x4162b380: 0x7a518d _ZN13File_OpenFile8truncateEyPK11sockAddressiP



Jul 27 07:03:10 2018:CS_PLATFORM:BoxMonitor:CRITICAL:302:::::Slot X has panicked.
Jul 27 07:03:18 2018:CS_PLATFORM:BoxMonitor:DEBUG:905:::::Slot X recover_slot /nas 2 has started.
Jul 27 07:03:41 2018:DART:UFS:WARNING:7:Slot X:::1532671409:File system <FSID>  is corrupted and will remain unmounted.
Jul 27 07:03:41 2018:DART:UFS:WARNING:48:Slot X:::1532671409:The file system <FSID> mount failed during failover because the file system was corrupt.

The problem happens due to a miscalculation when truncating a file leading to a negative value being calculated for the block count. This would be considered a rare issue as it only occurs under a very specific set of circumstances.

Upgrade to VNX OE release version 7.1.83.2 and install hotfix, the hotfix build number is 7.1.83.202.