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WARNING: 'Failed To Read Mirror Side 1' continuously reported in the alert log (Doc ID 1289905.1)

Last updated on MARCH 22, 2024

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 11.2]
Oracle Database Exadata Cloud Machine - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Information in this document applies to any platform.


Error continuously reported in the alert log:

WARNING: failed to read mirror side 1 of virtual extent 665 logical extent 0 of file 280 in group [1.445758315] from disk <DGNAME>_0005 allocation unit 75811 reason error; if possible,will try another mirror side 

Function List (to Full stack) (to Summary stack)

ksedsts <- ksdxfstk <- ksdxcb <- sspuser <- f0<- sdbgrfucf_close_file <- sdbgrfcf_close_file <-dbgrlWriteTextOnly<- dbgrlWriteAlertDetail_int <- dbgrlWriteAlertDetail<- dbgrlWriteAlertText <- dbkrlWriteAlertText <- dbkrlPril <- ksdfmw<- ksdwrt<- kfioCompleteIO <- kfioWaitIO <- kfioRequestPriv <-kfioRequest<- ksfd_kfioRequest<- ksfd_osmio <- ksfd_io <- ksfdread <- kcfrbd1 <- kcbzib<- kcbgcur <-kturRollbackToSavepoint <- ktcrsp1 <- ksures <-ksuxds<- kssdel <- kssdch <- ksudlp <- opidcl <- opidrv <- sou2o <- opimai_real <- ssthrdmain <- main


After upgrade to

You have already applied the patch for <bug:10051315> and <bug:10055063>.


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