[OpenIndiana-discuss] How does this even work?

[Jim Klimov]

20 февраля 2017 г. 2:48:14 CET, Cryptographrix <cryptographrix at gmail.com> пишет:
>root at nas:/etc# uname -a
>
>SunOS nas 5.11 oi_151a8 i86pc i386 i86pc Solaris
>
>
>root at nas:/etc# export OLD_DISK=c16t50014EE258D78C8Bd0
>
>
>root at nas:/etc# export NEW_DISK=c16t5000C500939587DBd0
>
>
>root at nas:/etc# prtvtoc /dev/rdsk/${OLD_DISK}
>
>* /dev/rdsk/c16t50014EE258D78C8Bd0 partition map
>
>*
>
>* Dimensions:
>
>*     512 bytes/sector
>
>* 3907029168 sectors
>
>* 3907029101 accessible sectors
>
>*
>
>* Flags:
>
>*   1: unmountable
>
>*  10: read-only
>
>*
>
>* Unallocated space:
>
>*       First     Sector    Last
>
>*       Sector     Count    Sector
>
>*          34       222       255
>
>*
>
>*                          First     Sector    Last
>
>* Partition  Tag  Flags    Sector     Count    Sector  Mount Directory
>
>       0      4    00        256 3907012495 3907012750
>
>       8     11    00  3907012751     16384 3907029134
>
>
>root at nas:/etc# iostat -E ${OLD_DISK}
>
>sd37      Soft Errors: 0 Hard Errors: 0 Transport Errors: 0
>
>Vendor: ATA      Product: WDC WD2002FYPS-0 Revision: 5G04 Serial No:
>WD-WCAVYNNNNNNN
>
>Size: 2000.40GB <2000398934016 bytes>
>
>Media Error: 0 Device Not Ready: 0 No Device: 0 Recoverable: 0
>
>Illegal Request: 0 Predictive Failure Analysis: 0
>
>
>root at nas:/etc# echo "p" | parted /dev/rdsk/${OLD_DISK}
>
>GNU Parted 1.8.8
>
>Using /dev/rdsk/c16t50014EE258D78C8Bd0
>
>Welcome to GNU Parted! Type 'help' to view a list of commands.
>
>(parted) p
>
>Model: Generic Ide (ide)
>
>Disk /dev/rdsk/c16t50014EE258D78C8Bd0: 2000GB
>
>Sector size (logical/physical): 512B/512B
>
>Partition Table: gpt
>
>
>Number  Start   End     Size    File system  Name  Flags
>
> 1      131kB   2000GB  2000GB               zfs
>
> 9      2000GB  2000GB  8389kB
>
>
>(parted)
>
>root at nas:/etc# prtvtoc /dev/rdsk/${NEW_DISK}
>
>* /dev/rdsk/c16t5000C500939587DBd0 partition map
>
>*
>
>* Dimensions:
>
>*     512 bytes/sector
>
>* 3907029168 sectors
>
>* 3907029101 accessible sectors
>
>*
>
>* Flags:
>
>*   1: unmountable
>
>*  10: read-only
>
>*
>
>* Unallocated space:
>
>*       First     Sector    Last
>
>*       Sector     Count    Sector
>
>*          34       222       255
>
>*
>
>*                          First     Sector    Last
>
>* Partition  Tag  Flags    Sector     Count    Sector  Mount Directory
>
>       0      4    00        256 3907012495 3907012750
>
>       8     11    00  3907012751     16384 3907029134
>
>
>root at nas:/etc# iostat -E ${NEW_DISK}
>
>sd52      Soft Errors: 0 Hard Errors: 0 Transport Errors: 0
>
>Vendor: ATA      Product: ST2000DM006-2DM1 Revision: CC26 Serial No:
>NNNNNNNN
>
>Size: 2000.40GB <2000398934016 bytes>
>
>Media Error: 0 Device Not Ready: 0 No Device: 0 Recoverable: 0
>
>Illegal Request: 0 Predictive Failure Analysis: 0
>
>
>root at nas:/etc# echo "p" | parted /dev/rdsk/${NEW_DISK}
>
>GNU Parted 1.8.8
>
>Using /dev/rdsk/c16t5000C500939587DBd0
>
>Welcome to GNU Parted! Type 'help' to view a list of commands.
>
>(parted) p
>
>Model: Generic Ide (ide)
>
>Disk /dev/rdsk/c16t5000C500939587DBd0: 2000GB
>
>Sector size (logical/physical): 512B/512B
>
>Partition Table: gpt
>
>
>Number  Start   End     Size    File system  Name  Flags
>
> 1      131kB   2000GB  2000GB               zfs
>
> 9      2000GB  2000GB  8389kB
>
>
>(parted)
>
>
>root at nas:/etc# zpool replace --help
>
>invalid option '-'
>
>usage:
>
>        replace [-f] <pool> <device> [new-device]
>
>
>
>root at nas:/etc# zpool replace -f rspool ${OLD_DISK} ${NEW_DISK}
>
>cannot replace c16t50014EE258D78C8Bd0 with c16t5000C500939587DBd0:
>devices
>have different sector alignment
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Googling for your disk models reveals that WD one has 512b native sectors, while the Seagate is 4k native and 512e emulated. Probably the defaults for sd.conf or some lower-level sd (scsi) magic exposes this, so zfs refuses to take it as a replacement. Possibly you can override via sd.conf to make-believe Segate can do 512byte sectors, at expense of RMW done behind curtains and slowing down small random writes. 

Jim
--
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